1. Most second-stage delivery modes, including operative vaginal delivery and second-stage cesarean delivery, are associated with similar neurodevelopmental outcomes in children. However, sequential instrument delivery is associated with a higher risk of attention deficit/hyperactivity disorder, and vacuum delivery is associated with a higher risk of intellectual disability.
Evidence Rating Level: 2 (Good)
Some of the most common neurodevelopmental disorders include attention deficit/hyperactivity disorder (ADHD) (5%-7%), autism spectrum disorder (ASD) (1%-2%) and intellectual disability (ID) (0.4%-1%), influenced by genetic and non-genetic factors. Previous research has suggested that children born by cesarean or operative vaginal delivery may have a higher risk of ADHD, ASD, and ID compared to spontaneous vaginal delivery (SVD). However, most past studies have relied on broad comparisons between cesarean sections and vaginal deliveries, which can be misleading due to confounding factors. To address this gap, this study aimed to evaluate how the second-stage delivery mode relates to the development of ADHD, ASD, and ID. This retrospective cohort study assessed new diagnoses of ADHD, ASD, and ID from one year of age until the conclusion of the study. A total of 504,380 children (44,202 [8.8%] with a maternal history of neurodevelopmental or psychiatric disorders) were included. Of these, 407,792 (80.9%) were delivered by SVD, 46,493 (9.2%) by vacuum, 23,140 (4.6%) by forceps, 3,009 (0.6%) by sequential instrument, and 23,946 (4.7%) by second-stage cesarean delivery (SSCD). Over the study period, the incidence of ADHD was 6.6 per 1000 person-years (95% CI, 6.5-6.7), with 7,693 cases and a median follow-up of 11.6 years (IQR, 7.2-16.8). The incidence of ASD was 1.8 per 1000 person-years (95% CI, 1.7-1.8) with 2,131 cases and a median follow-up of 12.5 years (IQR, 7.6-17.4). Lastly, the incidence of ID was 0.3 per 1000 person-years (95% CI, 0.2-0.3) with 323 cases and a median follow-up of 12.6 years (IQR, 7.8-17.5). Compared with SSCD, children born by sequential instrument delivery had a 13% higher rate of ADHD (7.9 [95% CI, 7.1-8.8] vs 6.6 [95% CI, 6.3-6.9] per 1000 person-years; adjusted hazard ratio [AHR], 1.13 [95% CI, 1.00-1.28]), and those born by vacuum delivery had a 53% higher rate of ID (0.3 [95% CI, 0.3-0.4] vs 0.2 [95% CI, 0.1-0.3] per 1000 person-years; AHR, 1.53 [95% CI, 1.12-2.10]). Overall, second-stage cesarean and operative vaginal deliveries generally have comparable neurodevelopmental outcomes, though certain interventions, such as vacuum delivery and sequential instruments, may increase the risk of ADHD and ID, highlighting the need for future research on delivery mode.
Click here to read the study in JAMA Network Open
Image: PD
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