Prevalence and associated factors for dysmenorrhea, heavy menstrual bleeding, and premenstrual syndrome in adolescent schoolgirls in Sudan.

This study focuses on menstrual abnormality and associated factors in schoolgirls in the Almatamah locality, a rural area in northern Sudan. The study design is cross-sectional and includes a sample of 162 girls selected from three schools through convenience sampling from January to May 2022. The girls were approached in the classroom, and the aim of the study was discussed. All girls who had attained menarche were enrolled in the targeted schools and provided written consent from a parent or guardian (sent to them in their homes and collected the next day), and were eligible to participate in the study. Premenarchal girls, those with a significant or chronic medical condition or bleeding disorder, who were married, pregnant, or taking hormonal medication, or who did not provide written consent, were excluded from the study. A face-to-face interview was conducted to fill out the questionnaire. The questionnaire consisted of sociodemographic data, such as age and mother’s education. Then, the girls were asked about menstrual characteristics, menarche, menstrual abnormalities, and questions regarding premenstrual symptoms (Additional file 1). Weight and height were measured using standard procedures, BMI was computed using the standard formula—weight in kg/height in m2—, and hemoglobin levels were measured. From each participant, 2 ml of venous blood (antecubital vein) was drawn in an Ethylene diamine tetraacetic acid tube to measure hemoglobin level, following the manufacturer’s instructions (Sysmex KX-21, Kobe, Japan). The International Federation of Gynecology and Obstetrics (FIGO) system of nomenclature for symptoms of normal and abnormal uterine bleeding (AUB) in the reproductive years (FIGO AUB System 1, revised in 2018) was used [ 23 ]. Menstrual flow volume is self-reported by the participant as light, normal, or heavy (excessive menstrual blood loss that negatively impacts a woman’s physical, social, emotional, and/or material quality of life). Dysmenorrhea is the crampy, recurrent pain in the lower abdomen during menses [ 26 ]. PMS is the cyclic mood changes confined to the second half of the menstrual cycle [ 27 ]. A total of 162 adolescent girls were included in this study. To ensure an appropriate sample size, we assumed that 12.0% of adolescent girls have menstrual abnormalities. There is no data on this problem in Sudan; this assumption was based on the reports from the nearby country (Ethiopia) [ 14 ]. The minimum sample size was calculated using a single proportional formula ( n  = Z 2 pq/d 2 ). Q = (1-p), Z1-α = confidence interval of 95% = 1.96, d = margin of error 5% = 0.05. Data were analyzed using the Statistical Package for the Social Sciences (IBM SPSS Statistics, Version 25.0). The normality of distribution for continuous data was tested using the Shapiro–Wilk test, which was found to be normally distributed and expressed as mean and standard deviation (SD). Descriptive statistics were obtained for demographic variables, menstrual characteristics, and all measurements. Univariate binary analyses were performed with each menstrual cycle characteristics (the presence of heavy menstrual bleeding, dysmenorrhea, symptoms of premenstrual syndrome, interference with daily activities, and the need for medical treatment) as dependent variables which were coded as 0 = no, 1 = yes) and independent variables, were age, hemoglobin level, BMI, gynecological age, mother’s education. Variables with P  < 0.020 in univariate binary analysis were shifted to build up a multivariate binary analysis to exclude confounders. Independent variables were tested for multicollinearity using the variation influence factor (VIF) ≥ 4, but no multicollinearity was detected. The adjusted odds ratios (AOR) and their corresponding 95% confidence intervals (95% CI) were calculated. A p-value of less than 0.05 was considered statistically significant.

A total of 162 adolescent girls were enrolled in the study. Their ages ranged between 12.78 and 18.87 years, with a mean (SD) of 15.78 (1.2) years. The mean (SD) age at menarche was 13.51 (1.1) years, and the mean (SD) gynecological age (chronological age minus age at menarche) was 2.28 (1.3) years. Their BMI ranged between 13.6 and 35.0, with a mean (SD) of 19.90 (3.36) kg/m 2 . The mean (SD) hemoglobin level was 12.58 (1.25) g/dl. Most mothers were illiterate (26.5%) or had an education level below secondary (level eleven) (61.7%), Table  1 . Table 1 Socio-demographic characteristics of adolescent girls ( n  = 162), sudan, 2022 Variable Mean (standard deviation) Age, years 15.78 (1.25) Body mass index, kg/m 2 19.90 (3.3) Age at menarche, years 13.51 (1.1) Gynecological age, years 2.28 (1.3) Hemoglobin level, g/dl 12.58 (1.2) Mother’s education level Frequency (percentage) Illiterate 43 (26.5) Less than secondary 100 (61.7) Secondary or higher 19 (11.7) Socio-demographic characteristics of adolescent girls ( n  = 162), sudan, 2022 Overall, 67.9% of the girls had at least one menstrual abnormality. 21% had heavy menstrual bleeding, 56.8% had dysmenorrhea, and 30.2% had symptoms of PMS. 13% of all girls claimed that symptoms accompanying their cycle interfered with their daily activities, with 17.3% reporting seeking medical attention to relieve the symptoms Table  2 . Sixty-seven (41.3%) of the girls had more than one of the menstrual abnormalities. Table 2 Prevalence of menstrual cycle abnormalities in adolescent girls ( n  = 162), sudan, 2022 Frequency Percentage Heavy menstrual bleeding Yes 34 21.0 No 128 79.0 Dysmenorrhea Yes 92 56.8 No 70 43.2 Premenstrual syndrome symptoms Yes 49 30.2 No 113 69.8 Premenstrual syndrome symptoms that interfere with daily activity Yes 21 13.0 No 141 87.0 Sought medical attention  Yes 28 17.3 No 134 82.7 At least one menstrual abnormality Yes 110 67.9 No 52 32.1 Prevalence of menstrual cycle abnormalities in adolescent girls ( n  = 162), sudan, 2022 Univariate analysis revealed that increasing gynecological age was associated with menstrual abnormality (OR = 1.53, 95% CI = 1.07–2.180). Chronological age, mother’s education, BMI, and hemoglobin were not associated with menstrual abnormality, Table  3 . Table 3 Univariate analysis of factors associated with menstrual cycle abnormalities in adolescent girls ( n  = 162), sudan, 2022 Variable Adolescents with menstrual abnormalities (number = 110) Adolescents with no menstrual abnormality (number = 52) Mean (standard deviation) Odds ratio (95% confidence interval) P Age, years 15.92 (1.24) 15.13 (1.25) 1.02 (0.73–1.43) 0.891 Gynecological age, years 2.51 (1.40) 1.80 (1.80) 1.5 (1.07–2.18) 0.019 Body mass index, kg/m 2 20.00 (3.50) 19.69 (3.04) 1.019(0.91–1.13) 0.722 Hemoglobin level, g/dl 12.52 (1.29) 12.70 (1.16) 0.85 (0.63–1.15) 0.307 Frequency (percentage) Mother’s education level < secondary 97 (88.2) 46 (88.5) Reference ≥ secondary 13 (11.8) 6 (11.5) 0.79 (0.26–2.37) 0.676 Univariate analysis of factors associated with menstrual cycle abnormalities in adolescent girls ( n  = 162), sudan, 2022 Increasing chronological age was associated with interference with daily activities. Increasing gynecological age was associated with heavy menstrual bleeding, dysmenorrhea, premenstrual symptoms, seeking medical attention, and interference with daily activities. Mother’s education and BMI were not associated with heavy menstrual bleeding, dysmenorrhea, premenstrual symptoms, seeking medical attention, and interference with daily activities, Table  4 . Table 4 Univariate binary regression analysis of factors associated with menstrual abnormalities in adolescent girls ( n  = 162), sudan, 2022 Variable Heavy menstrual bleeding Dysmenorrhea Premenstrual symptoms Sought medical attention Interference with activities AOR (95% CI) p OR (95% CI) p OR (95% CI) p OR (95% CI) p OR (95% CI) p Age 1.13 (0.85–1.52) 0.376 1.17 (0.92–1.50) 0.191 1.30 (0.99–1.71) 0.051 1.37 (0.98–1.90) 0.060 1.45 (1.01–2.12) 0.048 Mother’s education 6.67(0.28–1.54) 0.334 122(0.62–2.40) 0.556 0.98 (0.47–2.03) 0.967 1.13(0.56–3.19) 0.997 1.32 (0.71–2.44) 0.372 Gynecological age 1.29 (0.99–1.67) 0.052 1.46(1.12–1.90) 0.005 1.32 (1.03–1.69) 0.025 1.47 (1.10–1.95) 0.008 1.49 (1.09–2.03) 0.011 Body mass index, kg/m 2 1.06 (0.95–1.17) 0.260 0.91(0.90–109) 0.912 1.06 (0.96–1.17) 0.288 1.05 (0.93–1.18) 0.380 1.02(0.89–1.17) 0.699 OR odds ratios, CI confidence interval Univariate binary regression analysis of factors associated with menstrual abnormalities in adolescent girls ( n  = 162), sudan, 2022 OR odds ratios, CI confidence interval In logistic regression analysis, chronological age was not associated with menstrual abnormality. Increasing gynecological age was associated with heavy menstrual bleeding (AOR = 1.69, 95% CI = 1.20–2.38) and dysmenorrhea (AOR = 1.55, 95% CI = 1.12–2.14). Thus, every year increase in gynecological age was associated with a 1.69 increase in heavy menstrual bleeding and a 1.55 increase in dysmenorrhea. Gynecological age was not associated with PMS, seeking medical attention, or interference with daily activities) and thus it was considered a confounder in these, Table  5 . Table 5 Multivariate binary regression analysis of factors (age, mother’s education, and gynecological age) associated with menstrual abnormalities in adolescent girls ( n  = 162), sudan, 2022 Variable Heavy menstrual bleeding Dysmenorrhea Premenstrual symptoms Sought medical attention Interference with activities AOR (95% CI) p AOR (95% CI) p AOR (95% CI) p AOR (95% CI) p AOR (95% CI) p Age 1.19 (0.70–2.02) 0.514 1.13 (0.80–1.60) 0.458 1.05 (0.68–1.63) 0.799 1.13 (0.68–1.86) 0.622 Gynecological age 1.69 (1.20–2.38) 0.003 1.55(1.12–2.14) 0.007 1.22 (0.90–1.67) 0.193 1.42 (0.97–2.07) 0.066 1.39(0.92–2.10) 0.118 AOR  = adjusted odds ratios, CI  = confidence interval Multivariate binary regression analysis of factors (age, mother’s education, and gynecological age) associated with menstrual abnormalities in adolescent girls ( n  = 162), sudan, 2022 AOR  = adjusted odds ratios, CI  = confidence interval

The prevalence of dysmenorrhea, premenstrual syndrome symptoms, and heavy menstrual bleeding is high in Sudanese adolescent girls but is lower than in many studies from other countries. However, this conclusion should be interpreted cautiously as the definition of normal patterns adopted by different investigators varies widely. Further larger multicenter studies are recommended. A cross-sectional design, small sample size, and convenience sampling might limit generalizability. The questionnaire was not validated. The definition of heavy menstrual bleeding (HMB) was subjective. Other possible confounding factors (e.g., socioeconomic status, diet, stress levels) were not assessed.

The overall prevalence of menstrual abnormalities in this study was 67.9%. The most common abnormalities found were dysmenorrhea (56.8%), PMS (30.2%), and HMB (21.0%). Our results showed that 56.8% of the adolescent girls experienced some degree of pain during menstruation. These results are lower than those reported in several studies from around the world, which range between 75% and 93% [ 6 , 11 , 16 , 20 , 28 – 31 ]. For example, 71.8% of 246 students in Mekelle University’s health science program, Ethiopia, had dysmenorrhea [ 30 ]. Moreover, in a systematic review and meta-analysis, which included 12 studies in Ethiopia, the pooled prevalence of dysmenorrhea among female students was 71.69% [ 31 ]. Parker et al. reported a significant association between menstrual pain, premenstrual symptoms, and disruption of daily activities [ 6 ]. This underscores the significance of monitoring menstrual irregularities among adolescents, particularly in developing countries, where access to medical care and diagnostic services is limited. Our results demonstrated a significant association between dysmenorrhea and gynecological age. Shiferaw et al., Yahaya et al., and Pitangui et al. did not identify this association in Ethiopia, Malaysia, or Brazil [ 1 , 17 , 32 ]. This study found no significant association between dysmenorrhea and BMI, which agrees with several other studies [ 32 , 33 ]. Interestingly, Aouad et al., in a study of twins in Australia, found that primary dysmenorrhea in adolescents had a relatively strong genetic influence, which warrants further exploration of this association in our sample community [ 34 ]. In this study, 30.2% of girls reported at least one PMS symptom, with 13.0% indicating that these symptoms interfere with their daily activities, and 17.3% required some treatment. This prevalence is close to what Balaha et al.. found in Saudi Arabia (35.6%) [ 35 ]. The prevalence (30.2%) of PMS symptoms in the current study was higher than the prevalence (22%) of PMS symptoms reported among secondary and preparatory school students in Northeast Ethiopia [ 36 ]. However, it is significantly lower than that reported by other investigators [ 12 ]. For example, Abdelqadir et al.., Arafa et al. in Egypt, and Parker et al. in Australia reported 77.7%, 86.3%, and 73%, respectively [ 6 , 12 , 17 , 18 ]. The discrepancy can be attributed to varying data collection methods and characteristics of the study population. We found a significant association between increasing gynecological age and heavy menstrual bleeding and dysmenorrhea. Several associated factors have been reported in the literature. Parker et al. found significant associations between the severity of pain, the number of menstrual symptoms experienced, interference with life activities, and school absence in Australian adolescents, while Shiferaw et al.. in Ethiopia found that the educational status of mothers (having a diploma or higher) is likeliest to reduce PMS in their daughters by 55% compared to illiterate mothers [ 17 ]. We did not find an association between PMS and BMI, which contradicts other studies in the literature [ 10 ]. However, Arafa et al. and Balaha et al. reported an association with gynecological age in Egypt and Saudi Arabia, which aligns with our findings [ 18 , 35 ]. The difference in the socio-economic and nutritional factors could explain this. The menstrual flow volume in this study was normal in 79.0% of subjects, which is similar to that reported by Pitangui et al.. (77.0%) [ 1 ], Agarwal et al.. (81.7%) [ 20 ], and Marques et al.. (82.8%) [ 3 ]. Amu et al.. reported a prevalence of only 42.6% of normal flow volume among adolescent girls in southwestern Nigeria, but they assessed flow volume by the presence or absence of clots during menstruation, while we used participants’ self-reporting [ 16 ]. Heavy menstrual bleeding (HMB) is common among adolescent girls. In one large population-based study in Sweden, including 1019 healthy adolescent females, Friberg et al. found that approximately 36.8% had experienced HMB [ 37 ]. Our study showed a lower prevalence of HMB—21.0%—a finding comparable to those reported by Agarwal et al. in Singapore (14.5%) [ 20 ]. This discrepancy can be attributed to the latter studies being based on a school-going population, while the former was a community-based study. It is well known that HMB is a cause of school absenteeism [ 37 ], so many cases of HMB will be missed in school-based studies. Given that up to 20% of adolescents with HMB have an underlying bleeding disorder, the American College of Obstetricians and Gynecologists (ACOG) recommends that menstrual cycle assessment be considered an additional vital sign [ 37 , 38 ]. Other factors, such as stigma around menstruation) might influence reporting. We did not find a significant association between menstrual flow volume, chronological age, hemoglobin level, BMI, or mother’s education. In the literature, HMB was associated mainly with hormonal, clotting, or structural uterine abnormalities and certain medications [ 22 , 38 ].

The onset of the menstrual cycle, menarche, marks the beginning of the female reproductive age. It also occurs at a critical stage of life that is associated with significant physical, psychological, and sexual changes [ 1 ]. Moreover, it has been shown that more than 80% of adolescent girls have dysmenorrhea [ 2 , 3 ]. Several studies have shown that 47–73% of adolescents who reported severe pain and an inadequate response to medical treatment were diagnosed with endometriosis, a serious condition that may lead to further complications, such as chronic pelvic pain and infertility [ 4 – 6 ]. Heavy menstrual bleeding (HMB) is “excessive menstrual blood loss which interferes with the woman’s physical, emotional, social, and material quality of life, and which can occur alone or in combination with other symptoms” [ 7 ] It is a common cause of anemia in adolescents and is associated with bleeding disorders [ 8 , 9 ]. Another common menstrual abnormality is premenstrual syndrome (PMS), which affects 20–40% of menstruating women [ 10 ]. Common symptoms include fatigue, irritability, mood swings, depression, abdominal bloating, breast tenderness, acne, changes in appetite, and food cravings [ 10 ]. The reported prevalence is higher in adolescent girls (70–80%) [ 11 – 13 ]. PMS adds to the stress of adolescents’ lives and impacts their social and academic performance, necessitating various coping actions [ 14 , 15 ]. Varying rates of adolescent menstrual abnormality (HMB, dysmenorrhea, PMS) have been reported in the populations of neighboring countries [ 16 – 19 ]. Several factors, such as family history, educational status of parents, circumcision, and gynecological age, are associated with menstrual abnormalities in adolescents [ 3 , 17 , 20 ]. Furthermore, the effect of nutritional status and body mass index (BMI) has been studied with conflicting results [ 20 , 21 ]. Despite the vast number of studies on the prevalence of menstrual abnormality, the definitions of normal and abnormal cycles are inconsistent, making it challenging to compare the results of these studies [ 22 , 23 ]. Notably, 73% of adolescent girls reported feeling fear and anxiety during their first menstrual experience [ 24 ], indicating that improving young women’s knowledge about menstrual pain and coping strategies can improve the quality of life in this age group [ 15 , 25 ]. There is an obvious need to conduct more studies and adopt standard definitions to unify health messages regarding adolescent health. In Sudan, a country facing several health and economic challenges, there is a paucity of information about the situation of adolescent menstrual health and its impact on their lives. Research on menstrual and reproductive health is needed to generate data for researchers, health planners, and practicing physicians to base evidence-based interventions. This study aimed to investigate the prevalence and associated factors of heavy menstrual bleeding (HMB), dysmenorrhea, and premenstrual symptoms (PMS) in adolescent Sudanese schoolgirls.

Supplementary Material 1. Supplementary Material 1.