The Connection Between C-Sections and Autism

Cesarean section births initially tied to raised autism risk, but link did not persist in further analysis

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Babies born via cesarean section (C-section) may face a raised risk of autism, but that doesn't necessarily mean the C-section caused this raised risk.

Babies born by C-section may face an increased risk of having autism spectrum disorder (ASD), a new study found. However, this higher risk of ASD was more likely due to family factors like genetics or environment, rather than the C-section itself.

According to the Centers for Disease Control and Prevention, about one-third of babies are delivered by C-section every year. That rate has jumped from about 20 percent in 1996. While this operation can save a mother or child from injury or death in some cases, many critics have said that the surgery is often being performed on those who don’t need it — exposing many women and babies to possible surgical complications.

Ali S. Khashan, PhD, with the Irish Centre for Fetal and Neonatal Translational Research (INFANT) in Cork, Ireland, led this study.

Study co-author Louise C. Kenny, PhD, consultant obstetrician and gynecologist at Cork University Maternity Hospital, told dailyRx News that “The overall risk of ASD is very small and this most recent work suggests that most — if not all — the risk is not to do with the cesarean section. This should be reassuring for parents. Anyone concerned about their pregnancy or their baby should speak to their health care provider.”

Dr. Khashan and team reviewed data on about 2.7 million children born between 1982 and 2010. Just over 80 percent were born by unassisted vaginal delivery, and 7.3 percent were delivered via assisted vaginal delivery. The remainder were brought into the world via C-section. About half of these C-sections were elective. The other half were emergency procedures. A total of 28,290 children in this study (1 percent) were later diagnosed with ASD.

ASD is a disorder marked by impairment in social interaction and communication. Children with ASD may have repetitive behaviors and limited interest in normal childhood pursuits.

Birth by C-section was tied to a nearly 20 percent increased risk of ASD, compared to birth by vaginal delivery.

To determine whether the increased risk of ASD was caused by the C-section or an unknown factor, Dr. Khashan and colleagues analyzed 13,000 pairs of siblings in which one was diagnosed with ASD and one was not. In this analysis, these researchers no longer found any link between birth by C-section and ASD.

Because the link no longer persisted with the sibling controls, Dr. Khashan and team concluded that genetic and family environment factors may account for the increased risk of ASD, rather than the C-section itself.

Dr. Khashan stressed that more research is needed on the subject to better understand the link between C-section and other short- and long-term health outcomes in children.

This study was published online June 24 in JAMA Psychiatry. A grant from the Irish Centre for Fetal and Neonatal Translational Research funded this research. Dr. Khashan and team disclosed no conflicts of interest.

Review Date: 
June 24, 2015
Last Updated:
June 25, 2015