Burden and Nutritional Determinants of Metabolic Bone Disease of Prematurity in Very Low Birth Weight Infants: A Prospective Cohort Study from a Tertiary Neonatal Unit

Burden and Nutritional Determinants of Metabolic Bone Disease of Prematurity in Very Low Birth Weight Infants: A Prospective Cohort Study from a Tertiary Neonatal Unit | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Burden and Nutritional Determinants of Metabolic Bone Disease of Prematurity in Very Low Birth Weight Infants: A Prospective Cohort Study from a Tertiary Neonatal Unit HEMANT KUMAR, SUSHIL CHOUDHARY, KANUPRIYA RATHORE, ARUN SINGH, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8538023/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objectives To characterize the biochemical profile of metabolic bone disease of prematurity with specific emphasis on hypophosphatemia in very low birth weight (VLBW) or < 32 weeks’ infants in response to current practices of calcium, phosphate and vitamin D supplementation at 40 weeks of postmenstrual age. Methods This prospective cohort study was conducted in a tertiary care neonatal unit. VLBW or preterm infants < 32 weeks of gestation were enrolled. Serum calcium, phosphorus, alkaline phosphatase, and 25-hydroxyvitamin D levels were assessed at 4 weeks of postnatal age and at term-equivalent age (40 weeks postmenstrual age). Results A total of 102 neonates were enrolled, of whom 99 completed follow-ups. No infant developed hypocalcaemia at either assessment point. Hypophosphatemia was observed in 45 (44.1%) infants at 4 weeks and persisted in 35 (35.4%) infants at 40 weeks postmenstrual age. Vitamin D insufficiency and deficiency were present in 13.7% and 19.6% of infants at 4 weeks, respectively. Metabolic bone disease of prematurity was diagnosed in 19 (18.6%) infants. Lower average daily phosphorus intake was associated with a higher prevalence of metabolic bone disease, while calcium and vitamin D intake showed similar unadjusted associations (p < 0.001). Conclusion Hypophosphatemia was the most frequent biochemical abnormality observed in infants with metabolic bone disease of prematurity.. Despite routine supplementation, hypophosphatemia remained prevalent and was the strongest independent predictor of metabolic bone disease, underscoring phosphorus inadequacy as the primary driver of disease in VLBW infant. Metabolic bone disease of prematurity Vitamin D Calcium phosphorus Figures Figure 1 Figure 2 Introduction Due to the continuous advancement in the care of preterm infants, survival of these infants is progressively increasing [ 1 , 2 ]. Metabolic bone disease (MBD) of prematurity is one of the common morbidities encountered in these preterm neonates who have survived through aggressive NICU care. Metabolic bone disease (MBD) of prematurity, also known as osteopenia of prematurity (OOP), is characterized by decreased bone mineralization in preterm infants. In a term fetus, at least 80% of the calcium, phosphorus, and magnesium is accreted during the third trimester of pregnancy. Approximately 60 mg/day of calcium is transferred at 24 weeks, increasing to 300–350 mg/day between the 35th and 40th weeks of gestation. Similarly, the phosphorus transfer rate is around 40 mg/day at week 24 and rises to 200 mg/day after 35 weeks of gestation [ 3 ]. Being born before the critical intrauterine period for nutrient incorporation into the bone matrix results in the partial or complete loss of the optimal stage for acquiring mineral reserves. Consequently, preterm newborns are more susceptible to neonatal complications like defective bone mineralization [ 4 ]. Vitamin D is a fat-soluble vitamin with multiple roles in normal physiological processes. Vitamin D is essential in maintaining calcium and phosphorus homeostasis and depositing these minerals in bones [ 5 ]. Nursing infants are prone to vitamin D deficiency due to its limited presence in breast milk [ 6 ]. Metabolic bone disease of prematurity, also known as Osteopenia of prematurity (OOP), is a condition affecting premature infants characterized by reduced bone mineral content, primarily due to inadequate intake of calcium and phosphorus during early postnatal life. This condition predominantly affects preterm infants, with impaired bone growth and mineralization leading to both short-term consequences, such as prolonged dependence on ventilator support and increased risk of fractures, as well as long-term risks, such as reduced stature [ 7 ]. Fractures often occur without symptoms and are usually detected only through X-ray examinations. Fractures are becoming less common due to advancements in parenteral and enteral mineral supplementation. However, prospective and systematic skeletal surveys remain essential to assess fracture risk in very low birth weight infants [ 8 ]. The primary goal should be preventing bone disease in premature infants rather than treating it. Ensuring an early and adequate supply of calcium and phosphate is crucial. Modern parenteral solutions aim to match the accretion rates seen in utero, theoretically supporting optimal bone health. Unlike previous studies, this study quantifies actual received cumulative calcium, phosphorus, and vitamin D doses in VLBW infants and correlates them with biochemical MBD outcomes at term-equivalent age. The aim of conducting this study is to determine the prevalence of metabolic bone disease in the VLBW population at a tertiary care centre and to determine whether the current practice of Vitamin D calcium and phosphorus supplementation is sufficient in normalizing the Vitamin D level in the VLBW infants at term gestational age. Materials and methods Study setting: This prospective study was conducted at a tertiary care center with level III NICU from November 2022 to April 2024. Institute’s ethics committee approved the study protocol. Neonates of gestational age < 32 weeks or birth weight < 1500 grams were enrolled. Infants with gross congenital anomalies and who died within 28 days of birth were excluded from the study. Written informed consent was obtained after explaining the details of the study. Calcium, Phosphorus & Vitamin D Supplementation Parenteral and enteral nutrition was given to all the neonates as per unit protocol. Parenteral nutrition was started for all infants < 1250 grams, along with minimal enteral nutrition (MEN) of 10–20 ml/kg/day. Feed was increased gradually, with the rate of 10–30 ml/kg/day as per gestational age and birth weight. In total parenteral nutrition, calcium and phosphorus were supplemented in a dose of 60–80 mg/kg/day and 30–40 mg/kg/day respectively. Vitamin D was given through multivitamin injection (MVI)(1ml=100mg of vitamin D) in a dose of 150 IU/day (1.5ml/day of MVI injection). On enteral nutrition, supplementation of calcium, phosphorus, and vitamin D was done through fortification of expressed breastmilk with human milk fortifier (HMF, 1-gram HMF- 15 mg calcium 7.90 mg phosphorus) or a combination of calcium, phosphorus, zinc & vitamin D3 suspension ( 300 mg calcium,150 mg phosphate each 10 ml) and Vitamin D3 drops (1 ml 400 IU). Enteral feeds were given with either expressed mother’s own milk (MOM) or expressed donor human milk (EDHM). Neonates less than 32 weeks and with respiratory morbidities were given feeding with orogastric tube. Fortification of expressed milk with HMF was started when the infant reached 100–120 ml/kg/day feed volume. One sachet of 1g of HMF was mixed with 25 ml of expressed breastmilk. If the infant had feed intolerance after starting HMF, dilution was increased or stopped temporarily and started again when feed intolerance subsided. HMF was stopped after the infant attained 2kg of weight or there was an issue of non-affordability after the discharge. After stopping, HMF supplementation was continued with Syrup Calcium and vitamin D3 drops. HMF was given to all the infants during the entire period of NICU till 2kg of weight. Enteral supplementation of calcium, Phosphorus & vitamin D was given as per the American Academy of Paediatrics (AAP), with the minimum dose being 120 mg/kg/day, 60 mg/kg/day, and 400 IU/day for calcium, phosphorus, and vitamin D respectively. 3.Screening of MBD of Prematurity & Blood Sampling Screening of MBD of prematurity (Serum Ca, P, and ALP) was done for all the infants as per unit protocol. Serum calcium, phosphorus, and alkaline phosphatase were measured for the first time at 2–3 weeks for the infants who received TPN for more than two weeks and then repeated at four weeks of age and every two weeks after that. For other infants, the first MBD screening was done at four weeks and repeated every two weeks after that. MBD screening was stopped either at 40 weeks of postmenstrual age or correction of MBD of prematurity (ALP 5.5 mg/dl), whichever was later. Blood samples for 25(OH) D and PTH were collected along with samples for MBD screening at four weeks of life and 40 weeks of PMA. Mother’s blood sample for 25-Hydroxy Vitamin D {25(OH)D} were taken within 72 hours of delivery for all mothers. 4.Data Collection Maternal data of age, gravida, parity, booked and supervised, antenatal complications, multiple births, antenatal steroids, and mode of delivery was collected. All these maternal data were collected from maternal admission files and subsequent health records. Infant baseline data of gestational age, sex, birth weight, intrauterine growth, birth length, birth occipitofrontal circumference (OFC), APGAR at 1 & 5 minutes of life, total days of hospitalization, total days of ventilation ,total days of TPN and medication (caffeine, postnatal steroids, diuretics) was collected. AGA, SGA, or LGA was labelled as per birth weight centile using the Birth Intergrowth 21 chart. Hypocalcaemia and hypophosphatemia were defined as serum calcium 900 IU/L and serum phosphorus was < 5.5 mg/dl [ 12 – 14 ]. 100 ml of preterm breast milk contains 25.2 mg of calcium, 14.3 mg of phosphorus, and 5.8 IU of vitamin D[ 15 , 16 ]. Daily intake of calcium, phosphorus, and vitamin D was entered in the data monitoring sheet. Total intake was averaged over the entire period from day 1 of life till 40 weeks of age. If the infant is diagnosed with osteopenia of prematurity, the total intake was averaged over the period from day 1 of life till the time of diagnosis of MBD. After a diagnosis of MBD, infants were supplemented with an increased dose of calcium 200–220 mg/kg/day, phosphorus 100–115 mg/kg/day, and vitamin D 800–1200 IU/day. 5.Outcomes Primary outcome was to measure the proportion of VLBW infants with low levels of vitamin D, calcium and phosphate till 40 weeks of postmenstrual age in VLBW or < 32 weeks gestational age infants. Secondary outcome was to measure prevalence of MBD till 40 weeks of postmenstrual age. Other secondary outcome was to study the association between calcium, phosphate and vitamin D supplementation and the prevalence of MBD till 40 weeks of postmenstrual age. 6.Sample size Previous studies in similar population has demonstrated 7.58% prevalence of metabolic bone disease. Considering power of 80% and with the precision/absolute error of 5% calculated sample size was 98. We have considered 20% attrition due to lost to follow up and death before primary outcome, so final sample size was considered 120 neonates. 7.Statistical Analysis IBM SPSS version 25 software was used for data analysis. Normally distributed data were expressed in mean ± SD, and skewed data were expressed in median (IQR). Count data are reported as the number of cases (percentages), and the chi-square test was used to compare proportions in the groups. Mean were compared by using ANOVA. Univariate analysis was used to find association between risk factors and metabolic bone disease. P values less than 0.05 were considered statistically significant. Results In our study, a total of 102 preterm neonates were enrolled. After discharge from NICU, one infant died at home and two were lost to follow-up, and 99 infants were followed until 40 weeks of postmenstrual age.. Baseline variables are described in Table 1 . The mean maternal age was 28.92 ± 5.2 years. Multiple gestations were observed in 18 (19.8%) mothers, of whom 11 delivered twins. Primigravidae constituted 41 (45.1%) of the cohort. Among antenatal complications, pre-eclampsia, pregnancy-induced hypertension, and gestational diabetes mellitus were present in 12 (13.18%), 24 (26.37%), and 13 (14.28%) mothers, respectively. Complete antenatal steroid coverage was documented in 39 (42.9%) mothers, and caesarean delivery was the predominant mode of birth (71.4%). The median maternal 25-hydroxyvitamin D level was 16.2 ng/ml (IQR 8.85–25.90). Table 1 Baseline maternal and neonatal data Baseline maternal data (n = 91) Maternal age in years * 28.92±5.2 Primigravida n (%) 41(45.1) Booked n (%) 24 (26.4) Multiple pregnancy n (%) 18 (19.8) Antenatal complications n (%) Preeclampsia 12 ( 13.18 ) Pregnancy induced hypertension 24( 26.37) Gestational diabetes Mellitus 13( 14.28) Antenatal steroid n (%) 39 (42.9) Mode of delivery n (%) Vaginal delivery 26(28.6) Caesarean Section 65(71.4) 25(OH) Vitamin D level (ng/ml) # 16.20 (8.85,25.90) Baseline infant data (n = 102) Gestational age (weeks)* 30.57±0.47 32 weeks n (%) 27(26.5) Female sex n (%) 50 (49) Birth weight * 1235.16±314.38 1500 gram n (%) 17 (16.7) Small for gestational age 41(40.2) APGAR score < 5 at 1 min n (%) 33 (32.4) at 5 min n (%) 5 (4.9) Biochemical data at 4 weeks of age Serum calcium (mg/dl)* 9.62 ±0.76 Serum phosphorus (mg/dl)* 5.27 ±1.50 Serum ALP (IU/L)# 503.50(385.50, 648.0) Serum 25(OH)D level (ng/ml)# 25.78 (18.55, 34.43) Serum PTH (pg/ml)# 30.42(12.95,56.81) Data are represented as n (%),*Mean+/-S.D, and #median (25th-75th interquartile range). n (%) denotes the number of total subjects with their percentage in brackets. ALP-alkaline phosphate, PTH – parathyroid hormone TPN- total parental nutrition Of the 102 infants recruited, 50 (49%) were female. The mean gestational age was 30.57 ± 0.47 weeks. Fourteen infants (13.7%) were born before 28 weeks, 61 (59.8%) between 28–32 weeks, and 27 (26.5%) after 32 weeks of gestation. Birth weight was < 1000 g in 27 (26.5%) infants and between 1000–1500 g in 57 (55.9%) infants. Small-for-gestational-age status was noted in 41 (40.2%) infants. An APGAR score < 5 was observed in 33 (32.4%) infants at 1 minute and 5 (4.9%) infants at 5 minutes (Table 1 ). At 4 weeks of age, the mean serum calcium and phosphorus levels were 9.62 ± 0.76 mg/dl and 5.27 ± 1.50 mg/dl, respectively (Table 2 ). The median serum ALP, serum 25-hydroxyvitamin D, and serum PTH levels were 503.50 IU/L (IQR 385.50–648.0), 25.78 ng/ml (IQR 18.55–34.43), and 30.42 pg/ml (IQR 12.95–56.81), respectively. At 40 weeks of PMA, mean serum calcium and phosphorus levels were 9.67 ± 0.48 mg/dl and 5.49 ± 1.17 mg/dl, respectively (Supplementary Table 1). The median serum ALP, serum 25-hydroxyvitamin D, and serum PTH levels at this time point were 636.0 IU/L (IQR 450–785), 31.80 ng/ml (IQR 22.18–53.7), and 21.12 pg/ml (IQR 12.03–54.5), respectively. Table 2 Serum Phosphorus, Calcium and Vitamin D deficiency at 4 weeks postnatal age Variables Hypophosphatemia Serum phosphorus* P value Serum calcium P value Vitamin D deficiency P value (n = 102) 45 (44.1%) 5.27 ±1.50 9.62±0.76 20(19.6) Gestational age 32 weeks (n = 27) 14(51.9) 5.07±0.80 9.64±0.49 (n = 27) 8(29.6) Birth weight <1000gm (n = 28) 20 (71.4) 4.43±1.57 1500gm (n = 17) 3 (17.7) 6.10±1.07 9.62±0.78 (n = 17) 3(17.6) Intrauterine growth SGA (n = 41) 25 (60.98) 4.66 ±1.30 0.015 9.63±0.68 (n = 41) 0.87 12 (29.27) 0.098 AGA (n = 60) 20 (33.33) 5.66±1.99 9.62±0.82 (n = 60) 7 (11.67) LGA (n = 1) 0 7.1 9.2 (n = 1) 1 (100) Data are represented as n (%), *Mean ± S.D ,n (%) denotes the number of total subjects with their percentage in brackets, Hypocalcaemia- serum calcium < 7 mg/dl SGA- Small for gestational age ( birth weight 90th centile for gestational age) By 40 weeks of PMA, 19 of 102 infants (18.6%) fulfilled the biochemical criteria for metabolic bone disease of prematurity (Table 3 ). The prevalence of MBD was 35.7% in infants 32 weeks of gestation. Among birth-weight categories, 35.7% of infants weighing 1500 g. MBD was more frequently observed in SGA infants (29.3%) compared with AGA infants (11.7%). Table 3 Prevalence of metabolic bone disease of prematurity Variables Metabolic bone disease of prematurity (n = 19) P Value Total (n = 102) 19 (18.6) Gestational age 32 weeks (n = 27) 4 (14.8) Weight 1500 gm (n = 17) 0 (0) Intrauterine growth Small for gestational age (n = 41) 12 (29.3) 0.066 Appropriate for gestational age (n = 60) 7 (11.7) Large for gestational age (n = 1) 0 (0) n (%) denotes the number of total subjects with their percentage in brackets Metabolic bone disease - Alkaline phosphatase > 900IU/L and serum phosphate < 5.5 mg/dl Among infants receiving 90 mg/kg/day (Fig. 1 ). The association between phosphorus intake and MBD was statistically significant (p < 0.001). Similarly, all infants receiving < 400 IU/day of vitamin D developed MBD, whereas 5 of 50 (10%) infants receiving 400–800 IU/day and 7 of 37 (18.9%) infants receiving 800–1200 IU/day developed MBD. No cases of MBD were observed among infants receiving > 1200 IU/day (Fig. 2 ). Vitamin D intake was significantly associated with MBD (p < 0.001). Maternal vitamin D levels were not significantly associated with the occurrence of MBD in infants. With respect to calcium intake, 8 of 9 (88.8%) infants receiving 200 mg/kg/day of calcium developed MBD (Table 4 ). Calcium supplementation showed a significant unadjusted association with MBD (p < 0.001). Table 4 Association of daily calcium, phosphorus and Vitamin D supplementation with MBD of prematurity MBD of prematurity n (%) P Value Average daily Vitamin D supplementation < 0.001 1200 (n = 8 ) 0 Average daily Calcium supplementation < 0.001 < 120 mg/kg/day (n = 9) 8 (88.8%) 120–160(n = 64) 9 (14.0%) 160–200 (n = 29) 2 (6.9%) Average daily Phosphorus supplementation < 0.001 90 mg/kg/day (n = 2) 1 (50%) n (%) denotes the number of total subjects with their percentage in brackets p value is calculated by Chi-square test/ Fischer exact test, p value 900IU/L and serum phosphate < 5.5 mg/dl Discussion Serum calcium, phosphorus, and 25 Hydroxy vitamin D levels were documented at at term-equivalent age (40 weeks postmenstrual age). The proportion of infants with hypocalcemia (serum calcium < 7 mg/dl) and hypophosphatemia (serum phosphorus 20 ng/ml), insufficiency (15–20 ng/ml), deficiency ( 100 ng/ml) [ 17 ]. All infants had normal serum calcium at 4 weeks of postnatal age (n = 99). This finding is likely related to early and consistent calcium supplementation practices in our unit, where all neonates receiving parenteral nutrition were started on intravenous calcium from day one. Enteral calcium supplementation was initiated once feeds reached 120 mg/kg/day. The absence of hypocalcemia may also reflect the tight physiological regulation of serum calcium, whereby transient early neonatal hypocalcemia related to low parathormone levels is followed by effective hormonal feedback control mediated by parathormone and calcium-sensing receptors [ 18 , 19 ]. In our study, hypophosphatemia was observed in 44.1% of infants at term-equivalent age, making it the most frequent biochemical abnormality. This finding may reflect unit-specific parenteral nutrition practices, as phosphate is not routinely added during the initial days of life. In addition, clinical instability and systemic illness in extremely preterm and sick neonates often prioritize acute management over optimal mineral supplementation. The only available parenteral phosphorus preparation in our unit is combined with potassium, and clinicians frequently avoid its early use due to concerns regarding renal dysfunction and electrolyte imbalance. Interruptions in calcium, phosphorus, and vitamin D supplementation during periods of acute illness may further contribute to suboptimal mineral intake. At 4 weeks of postnatal age, vitamin D insufficiency and deficiency were present in 13.7% and 19.6% of infants, respectively. These findings differ from those reported by Adnan et al., where no infant was found to have vitamin D insufficiency or deficiency following supplementation of 120–400 IU/day [ 20 ]. However, our results are consistent with reports by Matejek et al. and Tergestina et al., who documented a substantial proportion of VLBW infants with serum vitamin D levels < 20 ng/ml despite routine supplementation [ 21 – 23 ]. In the present study, 18.6% of infants developed metabolic bone disease of prematurity by 40 weeks of postmenstrual age, which is comparable to the prevalence reported in Indian cohorts by Kolisambeevi et al. (20.9%) [ 24 ] and Krithika et al. (17%) [ 25 ]. Lower received intake of calcium, phosphorus, and vitamin D was associated with a higher prevalence of metabolic bone disease, whereas infants receiving higher cumulative doses demonstrated a lower incidence. These associations should be interpreted cautiously, given the observational design of the study. Nevertheless, our findings are consistent with the meta-analysis by Vervesou et al., which demonstrated improved bone mineralization with higher combined doses of calcium, phosphorus, and vitamin D (standardized mean difference 1.72; 95% CI 0.85–2.16) [ 26 ]. We also evaluated the association between maternal vitamin D status and metabolic bone disease in preterm infants. Maternal vitamin D levels at delivery were not significantly associated with the occurrence of metabolic bone disease in infants (p = 0.237). This is in agreement with findings by Levkovitz et al., who reported that although maternal vitamin D levels correlated strongly with neonatal vitamin D levels at birth, they were not associated with neonatal bone strength as assessed by quantitative ultrasonography [ 27 ]. Strength of the study A key strength of this study is that actual received daily intakes of calcium, phosphorus, and vitamin D were calculated, rather than relying solely on prescribed doses. This allowed a pragmatic assessment of real-world supplementation practices in a tertiary-level neonatal unit. The prospective design and high follow-up rate until term-equivalent age further strengthen the findings. However, accurate monitoring of mineral supplementation after discharge could not be ensured, despite regular follow-up and parental counselling. Bone mineral density assessment using DEXA scanning, which could have provided a more direct measure of bone mineralization, was not feasible. In addition, differences in bioavailability of minerals from various supplementation sources were not accounted for. In conclusion, hypophosphatemia emerged as the most prevalent biochemical abnormality in very low birth weight preterm infants and was associated with metabolic bone disease of prematurity. Lower cumulative mineral intake was associated with a higher prevalence of metabolic bone disease, highlighting the need for optimized and uninterrupted mineral supplementation strategies. Further prospective studies are required to determine optimal dosing strategies, particularly for phosphorus, in high-risk preterm populations. Conclusion In this prospective cohort of very low birth weight preterm infants, hypophosphatemia was the most frequent biochemical abnormality observed at term-equivalent age and was associated with metabolic bone disease of prematurity. Lower cumulative intake of calcium, phosphorus, and vitamin D was associated with a higher prevalence of metabolic bone disease, highlighting the gap between recommended and practically achieved mineral supplementation in routine neonatal care, particularly in small and clinically unstable infants. These findings underscore the need for optimized and uninterrupted mineral supplementation strategies in tertiary-level NICUs, especially with respect to phosphorus. Further prospective studies are required to define optimal dosing and timing of mineral supplementation in high-risk preterm populations. Abbreviations Ca Serum calcium P Serum Phosphorus ALP Alkaline Phosphatase 25(OH)D 25 Hydroxy-Vitamin D PTH Parathormone VLBW Very low birth weight PMA Postmenstrual age MBD Metabolic bone disease DEXA Dual Energy X-ray Absorptiometry SGA Small for gestational age AGA Appropriate for gestational age LGA Large for gestational age NICU Neonatal intensive care unit Declarations Funding Declaration: No external funding was available Disclaimer: The supplier of the drug or its representative has no role in the study design, conduct, and analysis and manuscript preparation. Declaration on competing interests : None declared Data Availability Statement : Data of the current study is available on request. Name of Ethics Committee: All India Institute of Medical Sciences, Jodhpur; Institutional Ethics Committee Human Ethics and Consent to Participate declarations : Written informed consent was obtained from the parents or legal guardians of all enrolled infants prior to participation. The study was conducted in accordance with the ethical principles of the Declaration of Helsink. Certificate Reference Number: AIIMS/IEC/2022/4202 dated 23/09/2022 Clinical trial number: not applicable Acknowledgement: None to declare References Sefidkar R, Zayeri F, Kazemi E, Salehi M, Dehnad A, Hafizi M (2021) A trend study of preterm infant mortality rate in developed and developing countries over 1990 to 2017. Iran J Public Health 50(2):369 Cao G, Liu J, Liu M, Global (2022) Regional, and National Incidence and Mortality of Neonatal Preterm Birth, 1990–2019. 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Indian Pediatr 59(11):841–846 Krithika MV, Balakrishnan U, Amboiram P, Shaik MSJ, Chandrasekaran A, Ninan B (2022) Early calcium and phosphorus supplementation in VLBW infants to reduce metabolic bone disease of prematurity: a quality improvement initiative. BMJ Open Qual 11(Suppl 1):e001841 Vervesou A, Diamantis DV, Maslin K, Carroll JH (2023) Different doses of phosphorus, calcium, and vitamin D in premature infants and their effect on bone mineralization: systematic review and meta-analysis. Nutrire 48(2):48 Levkovitz O, Lagerev E, Bauer-Rusak S, Litmanovitz I, Grinblatt E, Sirota GL et al (2022) Vitamin D Levels in Pregnant Women Do Not Affect Neonatal Bone Strength. Children 9(6):883 Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8538023","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":590352812,"identity":"6bb07e4f-b58d-4255-95ee-92e93b4c837f","order_by":0,"name":"HEMANT KUMAR","email":"","orcid":"","institution":"All India Institute of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"HEMANT","middleName":"","lastName":"KUMAR","suffix":""},{"id":590352813,"identity":"74cb7bcd-7c04-4da2-b246-44deb38b2545","order_by":1,"name":"SUSHIL CHOUDHARY","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA0UlEQVRIiWNgGAWjYDCCAyDCwELOvr0BzCBai4SxAc8BMINYLQwSiRskEsAMwjr4bh9/JvmjQMLYXPL51Q1ABgN/e3cCXi2S53LMpHkMJOQsZ+eU3ewBOkzizNkNeLUYnOFhkwb5heF2TtoNoF4gO5eQFnagwwwkEhtunkm7+Yc4LQxmEkDDEzfcYD92myhbJM/wGFsDVRpL9uSw3ZYxkOAh6Be+M+wPb/74YyPHz3782c03IEZ7L34tSIDHAEwSqxwE2B+QonoUjIJRMApGEAAA5wxD0sGgt5AAAAAASUVORK5CYII=","orcid":"","institution":"All India Institute of Medical Sciences","correspondingAuthor":true,"prefix":"","firstName":"SUSHIL","middleName":"","lastName":"CHOUDHARY","suffix":""},{"id":590352814,"identity":"fc5fe335-4704-4956-91d7-acea3c22536d","order_by":2,"name":"KANUPRIYA RATHORE","email":"","orcid":"","institution":"All India Institute of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"KANUPRIYA","middleName":"","lastName":"RATHORE","suffix":""},{"id":590352815,"identity":"e12dff74-8271-42c9-b7bd-aff67effbeda","order_by":3,"name":"ARUN SINGH","email":"","orcid":"","institution":"All India Institute of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"ARUN","middleName":"","lastName":"SINGH","suffix":""},{"id":590352816,"identity":"56425967-1ea1-4d16-8a07-fa1a98daf1d2","order_by":4,"name":"Choudri Muzafar Paswal","email":"","orcid":"","institution":"All India Institute of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Choudri","middleName":"Muzafar","lastName":"Paswal","suffix":""},{"id":590352817,"identity":"7efe8a25-64f0-48f8-b379-dc8f829312a9","order_by":5,"name":"Mithu Banerjee","email":"","orcid":"","institution":"All India Institute of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Mithu","middleName":"","lastName":"Banerjee","suffix":""}],"badges":[],"createdAt":"2026-01-07 07:23:56","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8538023/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8538023/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":102620694,"identity":"21021216-3a40-4e18-8091-c8d61acc4873","added_by":"auto","created_at":"2026-02-13 16:45:07","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":52152,"visible":true,"origin":"","legend":"\u003cp\u003eBar diagram showing proportion of infant with and without metabolic bone disease (MBD) while receiving phosphorus in dose of \u0026lt;60mg/kg/day, and \u0026gt;60 mg/kg/day\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8538023/v1/2a0d0a5d688633b86cdb1b08.png"},{"id":102620693,"identity":"3a8e1696-ef96-45d9-86ab-62a31e573cb3","added_by":"auto","created_at":"2026-02-13 16:45:07","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":53554,"visible":true,"origin":"","legend":"\u003cp\u003eBar diagram showing the proportion of infants with and without metabolic bone disease (MBD) while receiving Vitamin D in doses of \u0026lt;400, 400-800, 800-1200 and \u0026gt;1200 mg/kg/day\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8538023/v1/952f4116db5b9d7583181cb7.png"},{"id":103644827,"identity":"af9cced2-7b91-4204-8ddf-80e285f84af3","added_by":"auto","created_at":"2026-02-28 10:11:03","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":932034,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8538023/v1/ad6e687c-15f4-42bf-ba6f-d4eca07ae115.pdf"},{"id":102620695,"identity":"6aadb70c-872b-4d59-8618-d9a2987ad45a","added_by":"auto","created_at":"2026-02-13 16:45:07","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":14116,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementarymaterial.docx","url":"https://assets-eu.researchsquare.com/files/rs-8538023/v1/015f32696831af2ea63465c1.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Burden and Nutritional Determinants of Metabolic Bone Disease of Prematurity in Very Low Birth Weight Infants: A Prospective Cohort Study from a Tertiary Neonatal Unit","fulltext":[{"header":"Introduction","content":"\u003cp\u003eDue to the continuous advancement in the care of preterm infants, survival of these infants is progressively increasing [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Metabolic bone disease (MBD) of prematurity is one of the common morbidities encountered in these preterm neonates who have survived through aggressive NICU care. Metabolic bone disease (MBD) of prematurity, also known as osteopenia of prematurity (OOP), is characterized by decreased bone mineralization in preterm infants. In a term fetus, at least 80% of the calcium, phosphorus, and magnesium is accreted during the third trimester of pregnancy. Approximately 60 mg/day of calcium is transferred at 24 weeks, increasing to 300\u0026ndash;350 mg/day between the 35th and 40th weeks of gestation. Similarly, the phosphorus transfer rate is around 40 mg/day at week 24 and rises to 200 mg/day after 35 weeks of gestation [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Being born before the critical intrauterine period for nutrient incorporation into the bone matrix results in the partial or complete loss of the optimal stage for acquiring mineral reserves. Consequently, preterm newborns are more susceptible to neonatal complications like defective bone mineralization [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Vitamin D is a fat-soluble vitamin with multiple roles in normal physiological processes. Vitamin D is essential in maintaining calcium and phosphorus homeostasis and depositing these minerals in bones [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Nursing infants are prone to vitamin D deficiency due to its limited presence in breast milk [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eMetabolic bone disease of prematurity, also known as Osteopenia of prematurity (OOP), is a condition affecting premature infants characterized by reduced bone mineral content, primarily due to inadequate intake of calcium and phosphorus during early postnatal life. This condition predominantly affects preterm infants, with impaired bone growth and mineralization leading to both short-term consequences, such as prolonged dependence on ventilator support and increased risk of fractures, as well as long-term risks, such as reduced stature [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Fractures often occur without symptoms and are usually detected only through X-ray examinations. Fractures are becoming less common due to advancements in parenteral and enteral mineral supplementation. However, prospective and systematic skeletal surveys remain essential to assess fracture risk in very low birth weight infants [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe primary goal should be preventing bone disease in premature infants rather than treating it. Ensuring an early and adequate supply of calcium and phosphate is crucial. Modern parenteral solutions aim to match the accretion rates seen in utero, theoretically supporting optimal bone health. Unlike previous studies, this study quantifies actual received cumulative calcium, phosphorus, and vitamin D doses in VLBW infants and correlates them with biochemical MBD outcomes at term-equivalent age.\u003c/p\u003e \u003cp\u003eThe aim of conducting this study is to determine the prevalence of metabolic bone disease in the VLBW population at a tertiary care centre and to determine whether the current practice of Vitamin D calcium and phosphorus supplementation is sufficient in normalizing the Vitamin D level in the VLBW infants at term gestational age.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eStudy setting: This prospective study was conducted at a tertiary care center with level III NICU from November 2022 to April 2024. Institute\u0026rsquo;s ethics committee approved the study protocol. Neonates of gestational age\u0026thinsp;\u0026lt;\u0026thinsp;32 weeks or birth weight\u0026thinsp;\u0026lt;\u0026thinsp;1500 grams were enrolled. Infants with gross congenital anomalies and who died within 28 days of birth were excluded from the study. Written informed consent was obtained after explaining the details of the study.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eCalcium, Phosphorus \u0026amp; Vitamin D Supplementation\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e \u003cp\u003eParenteral and enteral nutrition was given to all the neonates as per unit protocol. Parenteral nutrition was started for all infants\u0026thinsp;\u0026lt;\u0026thinsp;1250 grams, along with minimal enteral nutrition (MEN) of 10\u0026ndash;20 ml/kg/day. Feed was increased gradually, with the rate of 10\u0026ndash;30 ml/kg/day as per gestational age and birth weight.\u003c/p\u003e \u003cp\u003eIn total parenteral nutrition, calcium and phosphorus were supplemented in a dose of 60\u0026ndash;80 mg/kg/day and 30\u0026ndash;40 mg/kg/day respectively. Vitamin D was given through multivitamin injection (MVI)(1ml=100mg of vitamin D) in a dose of 150 IU/day (1.5ml/day of MVI injection).\u003c/p\u003e \u003cp\u003eOn enteral nutrition, supplementation of calcium, phosphorus, and vitamin D was done through fortification of expressed breastmilk with human milk fortifier (HMF, 1-gram HMF- 15 mg calcium 7.90 mg phosphorus) or a combination of calcium, phosphorus, zinc \u0026amp; vitamin D3 suspension ( 300 mg calcium,150 mg phosphate each 10 ml) and Vitamin D3 drops (1 ml 400 IU). Enteral feeds were given with either expressed mother\u0026rsquo;s own milk (MOM) or expressed donor human milk (EDHM). Neonates less than 32 weeks and with respiratory morbidities were given feeding with orogastric tube.\u003c/p\u003e \u003cp\u003eFortification of expressed milk with HMF was started when the infant reached 100\u0026ndash;120 ml/kg/day feed volume. One sachet of 1g of HMF was mixed with 25 ml of expressed breastmilk. If the infant had feed intolerance after starting HMF, dilution was increased or stopped temporarily and started again when feed intolerance subsided. HMF was stopped after the infant attained 2kg of weight or there was an issue of non-affordability after the discharge. After stopping, HMF supplementation was continued with Syrup Calcium and vitamin D3 drops. HMF was given to all the infants during the entire period of NICU till 2kg of weight. Enteral supplementation of calcium, Phosphorus \u0026amp; vitamin D was given as per the American Academy of Paediatrics (AAP), with the minimum dose being 120 mg/kg/day, 60 mg/kg/day, and 400 IU/day for calcium, phosphorus, and vitamin D respectively.\u003c/p\u003e \u003cp\u003e3.Screening of MBD of Prematurity \u0026amp; Blood Sampling\u003c/p\u003e \u003cp\u003eScreening of MBD of prematurity (Serum Ca, P, and ALP) was done for all the infants as per unit protocol. Serum calcium, phosphorus, and alkaline phosphatase were measured for the first time at 2\u0026ndash;3 weeks for the infants who received TPN for more than two weeks and then repeated at four weeks of age and every two weeks after that. For other infants, the first MBD screening was done at four weeks and repeated every two weeks after that. MBD screening was stopped either at 40 weeks of postmenstrual age or correction of MBD of prematurity (ALP\u0026thinsp;\u0026lt;\u0026thinsp;500 IU/L and P\u0026thinsp;\u0026gt;\u0026thinsp;5.5 mg/dl), whichever was later. Blood samples for 25(OH) D and PTH were collected along with samples for MBD screening at four weeks of life and 40 weeks of PMA. Mother\u0026rsquo;s blood sample for 25-Hydroxy Vitamin D {25(OH)D} were taken within 72 hours of delivery for all mothers.\u003c/p\u003e \u003cp\u003e4.Data Collection\u003c/p\u003e \u003cp\u003eMaternal data of age, gravida, parity, booked and supervised, antenatal complications, multiple births, antenatal steroids, and mode of delivery was collected. All these maternal data were collected from maternal admission files and subsequent health records. Infant baseline data of gestational age, sex, birth weight, intrauterine growth, birth length, birth occipitofrontal circumference (OFC), APGAR at 1 \u0026amp; 5 minutes of life, total days of hospitalization, total days of ventilation ,total days of TPN and medication (caffeine, postnatal steroids, diuretics) was collected. AGA, SGA, or LGA was labelled as per birth weight centile using the Birth Intergrowth 21 chart.\u003c/p\u003e \u003cp\u003eHypocalcaemia and hypophosphatemia were defined as serum calcium \u0026lt;7mg/dl and less than 5 mg/dl, respectively [\u003cspan additionalcitationids=\"CR10\" citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. MBD of prematurity was diagnosed if serum alkaline phosphatase was \u0026gt;\u0026thinsp;900 IU/L and serum phosphorus was \u0026lt;\u0026thinsp;5.5 mg/dl [\u003cspan additionalcitationids=\"CR13\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. 100 ml of preterm breast milk contains 25.2 mg of calcium, 14.3 mg of phosphorus, and 5.8 IU of vitamin D[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Daily intake of calcium, phosphorus, and vitamin D was entered in the data monitoring sheet. Total intake was averaged over the entire period from day 1 of life till 40 weeks of age. If the infant is diagnosed with osteopenia of prematurity, the total intake was averaged over the period from day 1 of life till the time of diagnosis of MBD. After a diagnosis of MBD, infants were supplemented with an increased dose of calcium 200\u0026ndash;220 mg/kg/day, phosphorus 100\u0026ndash;115 mg/kg/day, and vitamin D 800\u0026ndash;1200 IU/day.\u003c/p\u003e \u003cp\u003e5.Outcomes\u003c/p\u003e \u003cp\u003ePrimary outcome was to measure the proportion of VLBW infants with low levels of vitamin D, calcium and phosphate till 40 weeks of postmenstrual age in VLBW or \u0026lt;\u0026thinsp;32 weeks gestational age infants. Secondary outcome was to measure prevalence of MBD till 40 weeks of postmenstrual age. Other secondary outcome was to study the association between calcium, phosphate and vitamin D supplementation and the prevalence of MBD till 40 weeks of postmenstrual age.\u003c/p\u003e \u003cp\u003e6.Sample size\u003c/p\u003e \u003cp\u003ePrevious studies in similar population has demonstrated 7.58% prevalence of metabolic bone disease. Considering power of 80% and with the precision/absolute error of 5% calculated sample size was 98. We have considered 20% attrition due to lost to follow up and death before primary outcome, so final sample size was considered 120 neonates.\u003c/p\u003e \u003cp\u003e7.Statistical Analysis\u003c/p\u003e \u003cp\u003eIBM SPSS version 25 software was used for data analysis. Normally distributed data were expressed in mean \u0026plusmn; SD, and skewed data were expressed in median (IQR). Count data are reported as the number of cases (percentages), and the chi-square test was used to compare proportions in the groups. Mean were compared by using ANOVA. Univariate analysis was used to find association between risk factors and metabolic bone disease. P values less than 0.05 were considered statistically significant.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eIn our study, a total of 102 preterm neonates were enrolled. After discharge from NICU, one infant died at home and two were lost to follow-up, and 99 infants were followed until 40 weeks of postmenstrual age.. Baseline variables are described in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The mean maternal age was 28.92\u0026thinsp;\u0026plusmn;\u0026thinsp;5.2 years. Multiple gestations were observed in 18 (19.8%) mothers, of whom 11 delivered twins. Primigravidae constituted 41 (45.1%) of the cohort. Among antenatal complications, pre-eclampsia, pregnancy-induced hypertension, and gestational diabetes mellitus were present in 12 (13.18%), 24 (26.37%), and 13 (14.28%) mothers, respectively. Complete antenatal steroid coverage was documented in 39 (42.9%) mothers, and caesarean delivery was the predominant mode of birth (71.4%). The median maternal 25-hydroxyvitamin D level was 16.2 ng/ml (IQR 8.85\u0026ndash;25.90).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBaseline maternal and neonatal data\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eBaseline maternal data (n\u0026thinsp;=\u0026thinsp;91)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaternal age in years *\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28.92\u0026plusmn;5.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrimigravida n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e41(45.1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBooked n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24 (26.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMultiple pregnancy n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18 (19.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAntenatal complications n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreeclampsia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12 ( 13.18 )\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePregnancy induced hypertension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24( 26.37)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGestational diabetes Mellitus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13( 14.28)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAntenatal steroid n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39 (42.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMode of delivery n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVaginal delivery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e26(28.6)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCaesarean Section\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e65(71.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e25(OH) Vitamin D level (ng/ml) #\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16.20 (8.85,25.90)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBaseline infant data\u003c/b\u003e (n\u0026thinsp;=\u0026thinsp;102)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGestational age (weeks)*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30.57\u0026plusmn;0.47\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;28 weeks n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14(13.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e28\u0026ndash;32 weeks n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e61 (59.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;32 weeks n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27(26.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFemale sex n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e50 (49)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBirth weight *\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1235.16\u0026plusmn;314.38\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;1000 gram n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28 ( 27.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1000\u0026ndash;1500 gram n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e57( 55.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;1500 gram n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17 (16.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSmall for gestational age\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e41(40.2)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAPGAR score\u0026thinsp;\u0026lt;\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eat 1 min n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e33 (32.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eat 5 min n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (4.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBiochemical data at 4 weeks of age\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerum calcium (mg/dl)*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.62 \u0026plusmn;0.76\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerum phosphorus (mg/dl)*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.27 \u0026plusmn;1.50\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerum ALP (IU/L)#\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e503.50(385.50, 648.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerum 25(OH)D level (ng/ml)#\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25.78 (18.55, 34.43)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerum PTH (pg/ml)#\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30.42(12.95,56.81)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eData are represented as n (%),*Mean+/-S.D, and #median (25th-75th interquartile range). n (%) denotes the number of total subjects with their percentage in brackets.\u003c/p\u003e \u003cp\u003eALP-alkaline phosphate, PTH \u0026ndash; parathyroid hormone TPN- total parental nutrition\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eOf the 102 infants recruited, 50 (49%) were female. The mean gestational age was 30.57\u0026thinsp;\u0026plusmn;\u0026thinsp;0.47 weeks. Fourteen infants (13.7%) were born before 28 weeks, 61 (59.8%) between 28\u0026ndash;32 weeks, and 27 (26.5%) after 32 weeks of gestation. Birth weight was \u0026lt;\u0026thinsp;1000 g in 27 (26.5%) infants and between 1000\u0026ndash;1500 g in 57 (55.9%) infants. Small-for-gestational-age status was noted in 41 (40.2%) infants. An APGAR score\u0026thinsp;\u0026lt;\u0026thinsp;5 was observed in 33 (32.4%) infants at 1 minute and 5 (4.9%) infants at 5 minutes (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eAt 4 weeks of age, the mean serum calcium and phosphorus levels were 9.62\u0026thinsp;\u0026plusmn;\u0026thinsp;0.76 mg/dl and 5.27\u0026thinsp;\u0026plusmn;\u0026thinsp;1.50 mg/dl, respectively (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The median serum ALP, serum 25-hydroxyvitamin D, and serum PTH levels were 503.50 IU/L (IQR 385.50\u0026ndash;648.0), 25.78 ng/ml (IQR 18.55\u0026ndash;34.43), and 30.42 pg/ml (IQR 12.95\u0026ndash;56.81), respectively. At 40 weeks of PMA, mean serum calcium and phosphorus levels were 9.67\u0026thinsp;\u0026plusmn;\u0026thinsp;0.48 mg/dl and 5.49\u0026thinsp;\u0026plusmn;\u0026thinsp;1.17 mg/dl, respectively (Supplementary Table\u0026nbsp;1). The median serum ALP, serum 25-hydroxyvitamin D, and serum PTH levels at this time point were 636.0 IU/L (IQR 450\u0026ndash;785), 31.80 ng/ml (IQR 22.18\u0026ndash;53.7), and 21.12 pg/ml (IQR 12.03\u0026ndash;54.5), respectively.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSerum Phosphorus, Calcium and Vitamin D deficiency at 4 weeks postnatal age\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHypophosphatemia\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSerum phosphorus*\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSerum calcium\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eVitamin D deficiency\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;102)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45 (44.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.27 \u0026plusmn;1.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.62\u0026plusmn;0.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e20(19.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eGestational age\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;28 weeks (n\u0026thinsp;=\u0026thinsp;14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10 (71.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.35\u0026plusmn;1.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e\u003cb\u003e0.027\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.95\u0026plusmn;1.36 (n\u0026thinsp;=\u0026thinsp;14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e0.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2(14.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e0.410\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e28\u0026ndash;32 weeks (n\u0026thinsp;=\u0026thinsp;61)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21(34.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.57 \u0026plusmn;1.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.54\u0026plusmn;0.66 (n\u0026thinsp;=\u0026thinsp;61)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10(16.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;32 weeks (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14(51.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.07\u0026plusmn;0.80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.64\u0026plusmn;0.49 (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e8(29.6)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eBirth weight\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;1000gm (n\u0026thinsp;=\u0026thinsp;28)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20 (71.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.43\u0026plusmn;1.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.84\u0026plusmn;1.10 (n\u0026thinsp;=\u0026thinsp;28)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e0.95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6(21.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e0.870\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1000-1500gm (n\u0026thinsp;=\u0026thinsp;57)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22 (38.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.4\u0026plusmn;1.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.52\u0026plusmn;0.49 (n\u0026thinsp;=\u0026thinsp;57)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e11(19.3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;1500gm (n\u0026thinsp;=\u0026thinsp;17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (17.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.10\u0026plusmn;1.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.62\u0026plusmn;0.78 (n\u0026thinsp;=\u0026thinsp;17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3(17.6)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eIntrauterine growth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSGA (n\u0026thinsp;=\u0026thinsp;41)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25 (60.98)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.66 \u0026plusmn;1.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e\u003cb\u003e0.015\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.63\u0026plusmn;0.68 (n\u0026thinsp;=\u0026thinsp;41)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e0.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e12 (29.27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e0.098\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAGA (n\u0026thinsp;=\u0026thinsp;60)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20 (33.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.66\u0026plusmn;1.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.62\u0026plusmn;0.82 (n\u0026thinsp;=\u0026thinsp;60)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7 (11.67)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLGA (n\u0026thinsp;=\u0026thinsp;1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.2 (n\u0026thinsp;=\u0026thinsp;1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1 (100)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"8\" nameend=\"c8\" namest=\"c1\"\u003e \u003cp\u003eData are represented as n (%), *Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;S.D ,n (%) denotes the number of total subjects with their percentage in brackets, Hypocalcaemia- serum calcium\u0026thinsp;\u0026lt;\u0026thinsp;7 mg/dl\u003c/p\u003e \u003cp\u003eSGA- Small for gestational age ( birth weight \u0026lt;\u0026thinsp;10th centile for gestational age), AGA- Appropriate for gestational age, LGA- Large for gestational age (percentile of birth weight \u0026gt;\u0026thinsp;90th centile for gestational age)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eBy 40 weeks of PMA, 19 of 102 infants (18.6%) fulfilled the biochemical criteria for metabolic bone disease of prematurity (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The prevalence of MBD was 35.7% in infants\u0026thinsp;\u0026lt;\u0026thinsp;28 weeks, 16.4% in those 28\u0026ndash;32 weeks, and 14.8% in infants\u0026thinsp;\u0026gt;\u0026thinsp;32 weeks of gestation. Among birth-weight categories, 35.7% of infants weighing\u0026thinsp;\u0026lt;\u0026thinsp;1000 g and 15.8% of those weighing 1000\u0026ndash;1500 g developed MBD, while no cases were observed in infants with birth weight\u0026thinsp;\u0026gt;\u0026thinsp;1500 g. MBD was more frequently observed in SGA infants (29.3%) compared with AGA infants (11.7%).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePrevalence of metabolic bone disease of prematurity\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMetabolic bone disease of prematurity (n\u0026thinsp;=\u0026thinsp;19)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eP Value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal (n\u0026thinsp;=\u0026thinsp;102)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19 (18.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eGestational age\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;28 weeks (n\u0026thinsp;=\u0026thinsp;14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (35.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e0.265\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e28\u0026ndash;32 weeks (n\u0026thinsp;=\u0026thinsp;61)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10 (16.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;32 weeks (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 (14.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eWeight\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;1000gm (n\u0026thinsp;=\u0026thinsp;28)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10 (35.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e\u003cb\u003e0.007\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1000\u0026ndash;1500 gm (n\u0026thinsp;=\u0026thinsp;57)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9 (15.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;1500 gm (n\u0026thinsp;=\u0026thinsp;17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eIntrauterine growth\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSmall for gestational age (n\u0026thinsp;=\u0026thinsp;41)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12 (29.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e0.066\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAppropriate for gestational age (n\u0026thinsp;=\u0026thinsp;60)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7 (11.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLarge for gestational age (n\u0026thinsp;=\u0026thinsp;1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003en (%) denotes the number of total subjects with their percentage in brackets\u003c/p\u003e \u003cp\u003eMetabolic bone disease - Alkaline phosphatase \u0026gt;\u0026thinsp;900IU/L and serum phosphate\u0026thinsp;\u0026lt;\u0026thinsp;5.5 mg/dl\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAmong infants receiving\u0026thinsp;\u0026lt;\u0026thinsp;60 mg/kg/day of phosphorus, 12 of 14 (85.7%) developed MBD, compared with 6 of 86 (6.9%) infants receiving 60\u0026ndash;90 mg/kg/day and 1 of 2 (50%) infants receiving\u0026thinsp;\u0026gt;\u0026thinsp;90 mg/kg/day (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The association between phosphorus intake and MBD was statistically significant (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eSimilarly, all infants receiving\u0026thinsp;\u0026lt;\u0026thinsp;400 IU/day of vitamin D developed MBD, whereas 5 of 50 (10%) infants receiving 400\u0026ndash;800 IU/day and 7 of 37 (18.9%) infants receiving 800\u0026ndash;1200 IU/day developed MBD. No cases of MBD were observed among infants receiving\u0026thinsp;\u0026gt;\u0026thinsp;1200 IU/day (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Vitamin D intake was significantly associated with MBD (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Maternal vitamin D levels were not significantly associated with the occurrence of MBD in infants.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eWith respect to calcium intake, 8 of 9 (88.8%) infants receiving\u0026thinsp;\u0026lt;\u0026thinsp;120 mg/kg/day developed MBD, compared with 9 of 64 (14%) infants receiving 120\u0026ndash;160 mg/kg/day and 2 of 29 (6.9%) infants receiving 160\u0026ndash;200 mg/kg/day. No infant receiving\u0026thinsp;\u0026gt;\u0026thinsp;200 mg/kg/day of calcium developed MBD (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Calcium supplementation showed a significant unadjusted association with MBD (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAssociation of daily calcium, phosphorus and Vitamin D supplementation with MBD of prematurity\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMBD of prematurity n (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eP Value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAverage daily\u003c/p\u003e \u003cp\u003eVitamin D supplementation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;400 IU (n\u0026thinsp;=\u0026thinsp;7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7 (100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e400\u0026ndash;800 IU (n\u0026thinsp;=\u0026thinsp;50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (10%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e800\u0026ndash;1200 IU (n\u0026thinsp;=\u0026thinsp;37)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7 (18.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;1200 (n\u0026thinsp;=\u0026thinsp;8 )\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAverage daily\u003c/p\u003e \u003cp\u003eCalcium supplementation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;120 mg/kg/day (n\u0026thinsp;=\u0026thinsp;9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8 (88.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e120\u0026ndash;160(n\u0026thinsp;=\u0026thinsp;64)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9 (14.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e160\u0026ndash;200 (n\u0026thinsp;=\u0026thinsp;29)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 (6.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAverage daily\u003c/p\u003e \u003cp\u003ePhosphorus supplementation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;60 mg/kg/day (n\u0026thinsp;=\u0026thinsp;14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12 (85.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e60\u0026ndash;90 mg/kg/day (n\u0026thinsp;=\u0026thinsp;86)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6 (6.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;90 mg/kg/day (n\u0026thinsp;=\u0026thinsp;2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (50%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003en (%) denotes the number of total subjects with their percentage in brackets\u003c/p\u003e \u003cp\u003ep value is calculated by Chi-square test/ Fischer exact test, p value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 considered significant\u003c/p\u003e \u003cp\u003eMBD- metabolic bone disease of prematurity- Alkaline phosphatase \u0026gt;\u0026thinsp;900IU/L and serum phosphate\u0026thinsp;\u0026lt;\u0026thinsp;5.5 mg/dl\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eSerum calcium, phosphorus, and 25 Hydroxy vitamin D levels were documented at at term-equivalent age (40 weeks postmenstrual age). The proportion of infants with hypocalcemia (serum calcium\u0026thinsp;\u0026lt;\u0026thinsp;7 mg/dl) and hypophosphatemia (serum phosphorus\u0026thinsp;\u0026lt;\u0026thinsp;5mg/dl) was assessd. According to the level of 25(OH) Vitamin D, infants were grouped into four subgroups, namely Vitamin D sufficiency (Vitamin D\u0026thinsp;\u0026gt;\u0026thinsp;20 ng/ml), insufficiency (15\u0026ndash;20 ng/ml), deficiency (\u0026lt;\u0026thinsp;15 ng/ml), and excess (\u0026gt;\u0026thinsp;100 ng/ml) [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAll infants had normal serum calcium at 4 weeks of postnatal age (n\u0026thinsp;=\u0026thinsp;99). This finding is likely related to early and consistent calcium supplementation practices in our unit, where all neonates receiving parenteral nutrition were started on intravenous calcium from day one. Enteral calcium supplementation was initiated once feeds reached 120 mg/kg/day. The absence of hypocalcemia may also reflect the tight physiological regulation of serum calcium, whereby transient early neonatal hypocalcemia related to low parathormone levels is followed by effective hormonal feedback control mediated by parathormone and calcium-sensing receptors [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn our study, hypophosphatemia was observed in 44.1% of infants at term-equivalent age, making it the most frequent biochemical abnormality. This finding may reflect unit-specific parenteral nutrition practices, as phosphate is not routinely added during the initial days of life. In addition, clinical instability and systemic illness in extremely preterm and sick neonates often prioritize acute management over optimal mineral supplementation. The only available parenteral phosphorus preparation in our unit is combined with potassium, and clinicians frequently avoid its early use due to concerns regarding renal dysfunction and electrolyte imbalance. Interruptions in calcium, phosphorus, and vitamin D supplementation during periods of acute illness may further contribute to suboptimal mineral intake.\u003c/p\u003e \u003cp\u003eAt 4 weeks of postnatal age, vitamin D insufficiency and deficiency were present in 13.7% and 19.6% of infants, respectively. These findings differ from those reported by Adnan et al., where no infant was found to have vitamin D insufficiency or deficiency following supplementation of 120\u0026ndash;400 IU/day [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. However, our results are consistent with reports by Matejek et al. and Tergestina et al., who documented a substantial proportion of VLBW infants with serum vitamin D levels\u0026thinsp;\u0026lt;\u0026thinsp;20 ng/ml despite routine supplementation [\u003cspan additionalcitationids=\"CR22\" citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn the present study, 18.6% of infants developed metabolic bone disease of prematurity by 40 weeks of postmenstrual age, which is comparable to the prevalence reported in Indian cohorts by Kolisambeevi et al. (20.9%) [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e] and Krithika et al. (17%) [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Lower received intake of calcium, phosphorus, and vitamin D was associated with a higher prevalence of metabolic bone disease, whereas infants receiving higher cumulative doses demonstrated a lower incidence. These associations should be interpreted cautiously, given the observational design of the study. Nevertheless, our findings are consistent with the meta-analysis by Vervesou et al., which demonstrated improved bone mineralization with higher combined doses of calcium, phosphorus, and vitamin D (standardized mean difference 1.72; 95% CI 0.85\u0026ndash;2.16) [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWe also evaluated the association between maternal vitamin D status and metabolic bone disease in preterm infants. Maternal vitamin D levels at delivery were not significantly associated with the occurrence of metabolic bone disease in infants (p\u0026thinsp;=\u0026thinsp;0.237). This is in agreement with findings by Levkovitz et al., who reported that although maternal vitamin D levels correlated strongly with neonatal vitamin D levels at birth, they were not associated with neonatal bone strength as assessed by quantitative ultrasonography [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eStrength of the study\u003c/p\u003e \u003cp\u003eA key strength of this study is that actual received daily intakes of calcium, phosphorus, and vitamin D were calculated, rather than relying solely on prescribed doses. This allowed a pragmatic assessment of real-world supplementation practices in a tertiary-level neonatal unit. The prospective design and high follow-up rate until term-equivalent age further strengthen the findings.\u003c/p\u003e \u003cp\u003eHowever, accurate monitoring of mineral supplementation after discharge could not be ensured, despite regular follow-up and parental counselling. Bone mineral density assessment using DEXA scanning, which could have provided a more direct measure of bone mineralization, was not feasible. In addition, differences in bioavailability of minerals from various supplementation sources were not accounted for.\u003c/p\u003e \u003cp\u003eIn conclusion, hypophosphatemia emerged as the most prevalent biochemical abnormality in very low birth weight preterm infants and was associated with metabolic bone disease of prematurity. Lower cumulative mineral intake was associated with a higher prevalence of metabolic bone disease, highlighting the need for optimized and uninterrupted mineral supplementation strategies. Further prospective studies are required to determine optimal dosing strategies, particularly for phosphorus, in high-risk preterm populations.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn this prospective cohort of very low birth weight preterm infants, hypophosphatemia was the most frequent biochemical abnormality observed at term-equivalent age and was associated with metabolic bone disease of prematurity. Lower cumulative intake of calcium, phosphorus, and vitamin D was associated with a higher prevalence of metabolic bone disease, highlighting the gap between recommended and practically achieved mineral supplementation in routine neonatal care, particularly in small and clinically unstable infants. These findings underscore the need for optimized and uninterrupted mineral supplementation strategies in tertiary-level NICUs, especially with respect to phosphorus. Further prospective studies are required to define optimal dosing and timing of mineral supplementation in high-risk preterm populations.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCa\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eSerum calcium\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eSerum Phosphorus\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eALP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eAlkaline Phosphatase\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e25(OH)D\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003e25 Hydroxy-Vitamin D\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePTH\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eParathormone\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eVLBW\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eVery low birth weight\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePMA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ePostmenstrual age\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMBD\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMetabolic bone disease\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eDEXA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eDual Energy X-ray Absorptiometry\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSGA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eSmall for gestational age\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eAGA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eAppropriate for gestational age\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eLGA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eLarge for gestational age\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eNICU\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eNeonatal intensive care unit\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding Declaration:\u003c/strong\u003e No external funding was available\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDisclaimer:\u003c/strong\u003e The supplier of the drug or its representative has no role in the study design, conduct, and analysis and manuscript preparation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDeclaration on competing interests\u003c/strong\u003e: None declared\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability Statement\u003c/strong\u003e: Data of the current study is available on request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eName of Ethics Committee:\u0026nbsp;\u003c/strong\u003eAll India Institute of Medical Sciences, Jodhpur; Institutional Ethics Committee\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHuman Ethics and Consent to Participate declarations\u003c/strong\u003e: Written informed consent was obtained from the parents or legal guardians of all enrolled infants prior to participation. The study was conducted in accordance with the ethical principles of the Declaration of Helsink.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCertificate Reference Number:\u0026nbsp;\u003c/strong\u003eAIIMS/IEC/2022/4202 dated 23/09/2022\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number:\u0026nbsp;\u003c/strong\u003enot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgement:\u0026nbsp;\u003c/strong\u003eNone to declare\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eSefidkar R, Zayeri F, Kazemi E, Salehi M, Dehnad A, Hafizi M (2021) A trend study of preterm infant mortality rate in developed and developing countries over 1990 to 2017. Iran J Public Health 50(2):369\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCao G, Liu J, Liu M, Global (2022) Regional, and National Incidence and Mortality of Neonatal Preterm Birth, 1990\u0026ndash;2019. JAMA Pediatr 176(8):787\u0026ndash;796\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKovacs CS (2016) Maternal Mineral and Bone Metabolism During Pregnancy, Lactation, and Post-Weaning Recovery. Physiol Rev 96(2):449\u0026ndash;547\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePinto MRC, Machado MMT, de Azevedo DV, Correia LL, Leite \u0026Aacute;JM, Rocha HAL (2022) Osteopenia of prematurity and associated nutritional factors: case\u0026ndash;control study. BMC Pediatr 22(1):519\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDawodu A, Nath R (2011) High prevalence of moderately severe vitamin D deficiency in preterm infants. Pediatr Int 53(2):207\u0026ndash;210\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eInstitute of Medicine (US) Committee to Review Dietary Reference Intakes for Vitamin D and Calcium. Dietary Reference Intakes for Calcium and Vitamin D [Internet]. Ross AC, Taylor CL, Yaktine AL Del Valle HB, editors. 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Indian Pediatr 59(11):841\u0026ndash;846\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKrithika MV, Balakrishnan U, Amboiram P, Shaik MSJ, Chandrasekaran A, Ninan B (2022) Early calcium and phosphorus supplementation in VLBW infants to reduce metabolic bone disease of prematurity: a quality improvement initiative. BMJ Open Qual 11(Suppl 1):e001841\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVervesou A, Diamantis DV, Maslin K, Carroll JH (2023) Different doses of phosphorus, calcium, and vitamin D in premature infants and their effect on bone mineralization: systematic review and meta-analysis. Nutrire 48(2):48\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLevkovitz O, Lagerev E, Bauer-Rusak S, Litmanovitz I, Grinblatt E, Sirota GL et al (2022) Vitamin D Levels in Pregnant Women Do Not Affect Neonatal Bone Strength. Children 9(6):883\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Metabolic bone disease of prematurity, Vitamin D, Calcium, phosphorus","lastPublishedDoi":"10.21203/rs.3.rs-8538023/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8538023/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjectives\u003c/h2\u003e \u003cp\u003eTo characterize the biochemical profile of metabolic bone disease of prematurity with specific emphasis on hypophosphatemia in very low birth weight (VLBW) or \u0026lt;\u0026thinsp;32 weeks\u0026rsquo; infants in response to current practices of calcium, phosphate and vitamin D supplementation at 40 weeks of postmenstrual age.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003e This prospective cohort study was conducted in a tertiary care neonatal unit. VLBW or preterm infants\u0026thinsp;\u0026lt;\u0026thinsp;32 weeks of gestation were enrolled. Serum calcium, phosphorus, alkaline phosphatase, and 25-hydroxyvitamin D levels were assessed at 4 weeks of postnatal age and at term-equivalent age (40 weeks postmenstrual age).\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eA total of 102 neonates were enrolled, of whom 99 completed follow-ups. No infant developed hypocalcaemia at either assessment point. Hypophosphatemia was observed in 45 (44.1%) infants at 4 weeks and persisted in 35 (35.4%) infants at 40 weeks postmenstrual age. Vitamin D insufficiency and deficiency were present in 13.7% and 19.6% of infants at 4 weeks, respectively. Metabolic bone disease of prematurity was diagnosed in 19 (18.6%) infants. Lower average daily phosphorus intake was associated with a higher prevalence of metabolic bone disease, while calcium and vitamin D intake showed similar unadjusted associations (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eHypophosphatemia was the most frequent biochemical abnormality observed in infants with metabolic bone disease of prematurity.. Despite routine supplementation, hypophosphatemia remained prevalent and was the strongest independent predictor of metabolic bone disease, underscoring phosphorus inadequacy as the primary driver of disease in VLBW infant.\u003c/p\u003e","manuscriptTitle":"Burden and Nutritional Determinants of Metabolic Bone Disease of Prematurity in Very Low Birth Weight Infants: A Prospective Cohort Study from a Tertiary Neonatal Unit","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-13 16:45:00","doi":"10.21203/rs.3.rs-8538023/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ac764c59-83e0-4dca-96cf-136096489512","owner":[],"postedDate":"February 13th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-05-05T18:38:47+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-13 16:45:00","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8538023","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8538023","identity":"rs-8538023","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}