High fetal head in cesarean link between delivery methods and complications.

A retrospective analysis was conducted on the clinical data of 236 patients who underwent cesarean section with a high-positioned fetal head at the First People’s Hospital of Longquanyi District, Chengdu from June 2023 to June 2024. Inclusion criteria: ① Meeting the diagnostic criteria for a high-positioned fetal head: defined as the fetal presenting part being ≥3 cm above the ischial spine. Assessment was conducted pre-operatively via vaginal examination and revalidated according to intraoperative findings after uterine incision to ensure consistency; ② The fetal presenting part being 3 cm or more above the ischial spine; ③ Pregnant women aged 18–45 years with a gestational age of ≥ 37 weeks. Exclusion criteria: ① Those suffering from mental illness and unable to cooperate; ② Those with severe coagulation disorders; ③ Patients whose fetal head delivery method was changed after the failure of one method (Cases with initial delivery method failure requiring alternative techniques were excluded to ensure outcomes reflect a single, consistent method and avoid confounding from mixed techniques). According to the fetal head delivery methods, the patients were divided into the manual fetal head delivery group ( n  = 80), the single-blade forceps group ( n  = 80), and the double-blade forceps group ( n  = 76). All parturients received combined spinal-epidural anesthesia. They were informed of the surgical methods and risks before the operation and signed the informed consent forms. There were no statistically significant differences in age, gestational age, body mass index, presenting part position, and the number of previous cesarean sections among the three groups of parturients ( p  > 0.05). See Table 1 for details. General conditions of the parturients in the three groups. This study was a retrospective analysis. The choice of fetal head delivery method was based on intraoperative real-time assessment: a fixed surgical team jointly determined the technique according to the degree of fetal head elevation (≥5 cm or 3–5 cm above the ischial spines), fetal position (occiput transverse or occiput anterior), and maternal pelvic conditions, with the primary principle being maternal and neonatal safety. Baseline analysis demonstrated balanced key variables across the three groups ( Table 1 ), mitigating the impact of selection bias. The surgical team consisted of a fixed two-person team proficient in three methods of fetal head delivery. The abdominal wall incision was a transverse arc-shaped incision 2–3 cm above the pubic symphysis. The position of the uterine incision was appropriately moved upward. After the uterus was incised and the membranes were ruptured, the amniotic fluid was aspirated as much as possible. The assistant applied pressure on the uterine fundus to press the fetal head below the uterine incision. Then, the primary surgeon inserted the right hand into the uterine cavity to grasp the fetal head, while the left hand pulled up the upper edge of the uterine incision close to the upper edge of the abdominal wall incision. The hand delivering the fetal head and the hand pressing on the uterine fundus coordinated with each other to deliver the fetal head. The single-blade forceps used in this study were Sellheim single-blade forceps (Model: Cesarean Section Single-blade Forceps 300, manufactured by Xinhua Surgical Instruments Co., Ltd., China), specifically designed for high-floating fetal heads in cesarean sections. Its structural advantages include a broad and uniform contact area with the fetal head, which helps distribute traction force evenly and reduces the risk of birth trauma. During the operation, when it was confirmed that the fetal head was in a high position, after aspirating the amniotic fluid, the fetal position was adjusted to the occipital transverse position. The primary surgeon held the single-blade forceps with the concave side upward in the left hand. The lower edge of the forceps slid along the direction guided by the right hand to the upper edge of the fetal ear. Then the right hand was removed, and both hands grasped the forceps handles to pull upward and outward. The assistant applied pressure on the uterine fundus to assist in the delivery of the fetal head [ 3 ]. Small cesarean section forceps were used. The method of applying the forceps was the same as that for vaginal forceps. Traction was applied towards the foot end of the parturient. When the fetal occiput reached the uterine incision, the forceps were removed to assist in the delivery of the fetal head. The surgeon inserted the right hand into the uterine cavity, grasped the fetal foot, performed internal version, and then delivered the fetus by breech extraction [ 4 ]. During the study period (June 2023–June 2024), only 3 cases underwent internal podalic version and breech extraction, all involving fetuses with an estimated weight <2500 g – a clinical scenario consistent with the application scope of breech extraction in cesarean section [ 5 ]. Due to the extremely small sample size, these cases were excluded from statistical analysis. Fetal delivery time, 1-minute Apgar score, umbilical artery blood pH value, neonatal asphyxia rate, incidence of birth trauma, incidence of uterine laceration, rate of inverted T-shaped incision, intraoperative blood loss (EBL), and incidence of puerperal infection. Several significant points warrant attention: Fetal delivery time was defined as the interval from completion of amniotic fluid aspiration (after membrane rupture) to full delivery of the fetal. Neonatal asphyxia was defined as a 1-minute Apgar score ≤ 7 combined with umbilical artery blood pH <7.20, and birth trauma included soft tissues, bones, nervous system, or internal organ injuries (e.g. facial abrasions/bruising) – both in line with standard obstetric criteria [ 1 ]. EBL was measured using a combination of suction canister volume and weighing of blood-soaked gauze (1  g  = 1 mL). Individual measurements were rounded to the nearest 50 mL. EBL was jointly estimated by the circulating nurse and the primary surgeon, with post-operative hemoglobin levels used to approximate confirmation. The Statistical Package for the Social Sciences (SPSS) Version 26.0 software (IBM Corp., Armonk, NY) was used for statistical analysis. Measurement data conforming to the normal distribution were expressed as mean ± standard deviation ( x ¯  ± s), and analyzed by analysis of variance and the SNK-q test. Normality of continuous variables (including umbilical artery pH) was verified using the Shapiro-Wilk test. Measurement data that did not conform to the normal distribution were expressed as median (P25, P75), and analyzed by the H test. For the comparison of categorical data, the χ 2 test or Fisher’s exact test (when a theoretical frequency was less than 1 or the number of cells with a theoretical frequency less than 5 exceeded 1/5) was used. The Bonferroni method was applied for the comparison of multiple rates. A p -value < 0.05 was considered to indicate a statistically significant difference.

There was no significant difference in age, gestational age, body mass index, position of first exposure, and proportion of scar uterus among the three groups ( p  > 0.05). The single-blade forceps group showed the shortest uterine incision-to-delivery time (19.48 ± 2.53 s, p  < 0.05), with all groups completing delivery within 60 s. The neonatal situation was compared: the 1-minute Apgar scores in all groups were 10, but the interquartile range in the manual delivery group (9,10) indicated a small proportion of neonates with slightly lower scores, whereas the single-blade and double-blade forceps groups showed a more consistent distribution (10,10); umbilical pH differences (7.34 ± 0.03 vs. 7.30 ± 0.05) were statistically significant ( p   0.05) with no extreme values; the median (P25, P75) for each group was: manual delivery group 7.30 (7.28, 7.33), single-blade forceps group 7.35 (7.33, 7.37), double-blade forceps group 7.32 (7.29, 7.35). Pairwise comparison showed the single-blade forceps group had a lower birth injury rate (including facial bruising, indentation, skull fracture, intracranial hemorrhage) than the other two groups ( p  < 0.05). The incidence of uterine laceration, inverted T incision, intraoperative bleeding, and puerperal infection in the three groups were compared in pairs: the number of inverted T incisions in the free-hand head delivery group was higher than that in the other two groups, and the difference was statistically significant ( p  < 0.05). The puerperal infection rate in the manual delivery group (12.5%) was higher than that in the single-blade forceps group (2.5%) and double-blade forceps group (5.3%), though the difference was not statistically significant ( p  = 0.219).

Cesarean section is an important means of managing high-risk pregnancies [ 6 ]. When properly applied, it plays a crucial role in reducing maternal and fetal complications and ensuring the safety of both the mother and the infant. Conversely, improper use can lead to severe maternal and neonatal complications. Therefore, it is of utmost importance to master the surgical indications and seize the appropriate surgical timing.The delivery of the fetal head during the operation is a key step in evaluating the smooth progress of the surgery. Difficulty in fetal delivery can result in neonatal asphyxia, low Apgar scores, fractures, brachial plexus injuries, an increased rate of transfer to the neonatal department, and even neonatal death. For the mother, it may lead to surgical side-injuries, uterine lacerations, visceral injuries, postpartum hemorrhage, and an increase in peri-operative complications. Difficulty in delivering the fetal head during cesarean section mainly occurs in cases such as a high-positioned fetal head, a deeply-sunken fetal head, anterior asynclitism, poor anesthesia effect, adenomyosis, and pregnancy complicated by obesity. A high-positioned fetal head is more commonly seen in elective cesarean sections, and it is more likely to occur in preterm births and in cases of smaller fetuses. If the primary surgeon lacks experience and applies improper force, it can also lead to a high-positioned fetal head and subsequent difficulty in head delivery. Regardless of which method is used for fetal head delivery, every effort should be made to avoid the occurrence of complications. It is necessary to identify early the situations that may lead to a high-positioned fetal head and make adequate pre-plans to reduce the occurrence of complications. Fetal delivery time and neonatal conditions: In terms of fetal delivery time, the single-blade forceps group had a significantly shorter fetal delivery time than the other two groups. The double-blade forceps group had a shorter delivery time than the manual fetal head delivery group, and the manual fetal head delivery group had a relatively longer head-delivery time. The primary clinical benefit of single-blade forceps was the 4-fold reduction in birth injuries (32.5%→7.5%), whereas shorter delivery times and marginal pH differences lacked clinical correlation. This aligns with evidence that sub-60-second intervals and pH variations < 0.05 rarely impact outcomes [ 7 ]. The non-significant difference in neonatal asphyxia rates (5% in manual group vs. 0% in others, p  = 0.328, Table 2 ) may be attributed to the small number of events (only 4 cases in the manual group), which limited statistical power to detect potential differences. Additionally, all neonates had Apgar scores ≥9 and pH ≥7.30, indicating mild or no hypoxia, which further explains the lack of significant differences. In terms of birth trauma, the single-blade forceps group had a significantly lower incidence than the other two groups. In the manual fetal head delivery group, 26 cases of birth trauma occurred, including 24 cases of facial cyanosis and 2 cases of intracranial hemorrhage, all of which healed without special treatment. In the double – blade forceps group, 6 cases of facial indentation occurred, and 30 cases of facial indentation were also found in the double-blade forceps group, all of which recovered spontaneously without special treatment. Comparison of delivery time and general situation of newborns in three groups. Note . Continue to use Bonferroni method or SNK-q test to compare in pairs, a means compared with the unhanded head delivery group, p  < 0.05; b means compared with the single-leaf forceps group, p  < 0.05. Comparison of maternal complications among three groups. Note . Continue to use the Bonferroni method to compare in pairs, a means that compared with the manual fetal head delivery group, p  < 0.05; b means that compared with the single-leaf forceps group, p  < 0.05. Maternal complications: The single-blade forceps group had significantly fewer maternal complications than the manual fetal head delivery group. In terms of the adoption of the inverted T-shaped incision, the manual fetal head delivery group had a higher rate than the other two groups. Regarding the higher rate of inverted T-incision in the manual delivery group, this decision was made based on intraoperative priorities: since the operator’s hand was already in the uterine cavity to facilitate manual extraction (as per preoperatively planned method), switching to alternate instruments would have required repeated manipulation, potentially stimulating the fetal head and increasing risks of neonatal adverse outcomes. To avoid such complications and prevent fetal head displacement, an inverted T-incision was performed to enlarge the uterine outlet, enabling rapid fetal delivery-aligning with the core goal of minimizing intra-operative fetal stress. There was no significant difference among the three groups in terms of intraoperative blood loss and the incidence of puerperal infection. We observed that the puerperal infection rate in the manual delivery group was higher than that in the single-blade forceps group and the double-blade forceps group. Although the difference was not statistically significant, this trend was consistent with the higher incidence of uterine lacerations, inverted T-incisions, and longer fetal delivery time in the manual group. Uterine lacerations and inverted T-incisions may disrupt the uterine barrier, and a longer fetal delivery time may prolong the exposure of intraoperative tissues to the external environment. These factors may collectively increase the risk of infection. However, due to the limited sample size, the difference did not reach statistical significance, which may be attributed to type II error. The above results confirm that single-blade forceps offer advantages for delivering high-positioned fetal heads during caesarean section. In clinical practice for high-positioned fetal head, standardized use of specialized extraction tools such as single-blade forceps is recommended in management protocols for reducing uterine trauma during delivery [ 8 ]. Additionally, they are easy to operate and less prone to slipping: the blades protect the fetal head to reduce facial injuries [ 9 ] and avoid repeated uterine manipulation, shortening tissue exposure time to reduce infection risk; meanwhile, optimized incision and extraction strategies can also balance surgical safety and maternal recovery outcomes [ 10 ]. Therefore, intraoperative assessment should be carefully conducted, the fetal position should be adjusted to the occipital transverse position according to the intraoperative situation, and full cooperation with the assistant should be achieved to improve the success rate of one-time fetal head delivery. The double-blade forceps in cesarean section provide relatively balanced force application, allowing for active traction and rotation of the fetal position. However, the abdominal wall incision has poor fixation relative to the pelvis, making the forceps prone to slipping. Repeated attempts to apply the forceps will prolong the fetal delivery time and increase the risk of neonatal birth trauma. Compared with forceps-assisted delivery, manual fetal head delivery requires more frequent uterine fundus pressure (poor for parturient experience), prolongs operation time, and increases risks of neonatal asphyxia and uterine incision laceration [ 11 ] – notably, prolonged manual manipulation and inverted T-incisions (more common in manual delivery) may reduce uterine integrity, which is a key factor affecting obstetric and perinatal outcomes in women undergoing subsequent assisted reproductive technology [ 12 ]. In emergencies, rectus abdominis muscle cutting (to address difficulty) may increase intraoperative blood loss and impair postoperative recovery – consistent with the clinical consensus that improper extraction techniques for impacted or high-positioned fetal head may increase the risk of uterine injury and affect subsequent uterine recovery [ 13 ]. While delivery method selection based on intraoperative judgment may introduce confounding by indication, this potential selection bias is mitigated by the balanced baseline characteristics (age, gestational age, BMI, etc.) across the three groups ( Table 1 , p  > 0.05) and the exclusion of cases requiring method switching to ensure consistent outcome reflection of single techniques. This study has certain limitations. As a retrospective analysis, the selection of fetal delivery methods relied on intraoperative assessments rather than randomization, which might introduce potential selection bias; however, balanced baseline characteristics across the three groups ( Table 1 ) help mitigate this concern. Given the retrospective design, formal power calculation and a priori effect-size estimation were not performed, but the observed significant differences in key outcomes (e.g. Four-fold reduction in birth injury rate in the single-blade forceps group) suggest the sample size ( n  = 236, divided into three groups) was sufficient to detect clinically meaningful effects. Additionally, cases requiring technique switching were excluded to focus on outcomes of a single successfully applied method, which may slightly restrict the generalizability to complex delivery scenarios. Moreover, the trend of puerperal infection in the manual delivery group lacked statistical significance due to sample size constraints, and the intraoperative blood loss estimation method has inherent limitations. Future research could further validate these findings by expanding the sample size, adopting randomized controlled designs to reduce bias, and incorporating cases with technique switching to analyze failure patterns and optimal rescue strategies. Additionally, long-term follow-up could be added to assess reproductive outcomes (e.g. uterine scar healing, subsequent pregnancy complications), as recommended in studies focusing on cesarean extraction and long-term uterine function [ 12 , 13 ] – thus providing more robust evidence for clinical practice.

In conclusion, delivering a healthy and unharmed newborn is the fundamental objective of cesarean section. When faced with difficulty in delivering a high-positioned fetal head, both single-blade and double-blade forceps-assisted delivery in cesarean section are effective in shortening the fetal delivery time and reducing maternal and neonatal complications, with the single-blade forceps showing more remarkable efficacy. Therefore, the correct approach is to conduct thorough pre-operative assessments and preparations (including personnel, instruments, anesthesia methods, body positions, incision selection, fetal delivery methods, and neonatal resuscitation). In cases of difficult fetal delivery during the operation, the advantages and disadvantages of various fetal head delivery methods should be compared based on the specific situation and the surgeon’s experience. Multiple delivery methods can even be combined to deliver the fetus as quickly and safely as possible, minimizing complications in both the newborn and the parturient and ensuring maternal and infant safety.

Difficulty in fetal delivery is a relatively common problem during cesarean section [ 1 ], with high-positioned fetal heads accounting for up to 50% of such cases. This difficulty can prolong fetal delivery time, increase neonatal birth trauma and asphyxia rates, and raise risks of uterine laceration and intraoperative blood loss [ 2 ]. The experience and operative skills of the surgeon are also important influencing factors. Therefore, to minimize the occurrence of various complications caused by a high-positioned fetal head during cesarean section and ensure the safety of the mother and the infant, determining which method of fetal head delivery should be adopted for high-positioned fetal heads during cesarean section to reduce maternal and neonatal complications has become a hot topic in clinical research. In this study, a retrospective analysis was conducted on the correlation between different methods of fetal head delivery for high-positioned fetal heads during cesarean section and obstetric complications, aiming to summarize the optimal method of fetal head delivery. The details are reported as follows.