Induced or augmented labor may be associated with an increased risk of autism, a new study finds.
Researchers discovered that mothers who had their labors induced, which stimulates contractions in the uterus, or augmented, which strengthens the duration and frequency of contractions, may be more likely to deliver a child with autism, especially if the baby is male. The study was published in the Aug. 12 edition of JAMA Pediatrics and was a joint study between researchers at Duke Medicine and the University of Michigan.
Autism, a developmental disorder characterized by social, communication and behavioral challenges, affects approximately one in 88 children across the country and is believed to be caused by a combination of genetic and environmental factors.
"We were careful in the paper to not identify where this association was coming from,” said Dr. Simon Gregory, associate professor of medical genetics and lead author of the study. “Based on the data, we do not know the circumstances that require induction or augmentation in the first place.”
While there has been past research on labor induction and autism, this study incorporates the largest set of subjects to date, Gregory noted. According to the paper, the researchers gathered data from 625,042 live births linked with North Carolina public school records. They found that male children who went through an induced or augmented labor have a 35 percent higher risk of having autism than those that did not.
Gregory added that although induced labor, which carries an increased risk for infections, is increasingly practiced in hospitals, there has been an overall decrease in maternal and fetal mortality.
“The findings of this study must be balanced with the fact that there are clear benefits associated with induction and augmentation of labor," said Dr. Chad Grotegut, co-author of the study and assistant professor of obstetrics and gynecology, in a press release. “Labor induction, especially for women with post-date pregnancies or medical conditions such as diabetes and high blood pressure, has remarkably decreased the chance of still birth.”
The findings do not suggest a causal relationship, but they do show a need for additional research. Gregory noted that the data used in this study did not have information on drugs that were used in the induction, the titration of the drug or the time frame in which the labor induction or augmentation took place. The next step of the research would be to examine each birth while factoring in these additional conditions.
“The birth cohort we examined in this study was across all of North Carolina,” Gregory said. “We want to look specifically at the mothers who gave birth at Duke Regional hospital to incorporate other factors such as mother’s health and fetus’ health.”
Funding for the study was provided by United States Environmental Protection Agency.