Today on Science & Sensibility, regular contributor Deena Blumenfeld takes a look at the recent study that examined a link between induction and augmentation of labor with an autism diagnosis in those same children during their school years. Did you have a chance to read the study? Take a look at what Deena found. – Sharon Muza, Community Manager, Science & Sensibility
As the parent of an autistic child, my ears perked up when I saw my Facebook feed (and Twitter and G+ feeds…) light up with links about the latest study on Autism. This time, it wasn’t vaccines or mercury they were talking about. It was labor induction and augmentation.
On August 12, 2013, JAMA sent out a press release regarding the study entitled: Association of Autism With Induced or Augmented Childbirth in North Carolina Birth Record (1990-1998) and Education Research (1997-2007) Databases. The media took note, and ran with it as evidenced by the following links:
- Medpage Today: Induced Labor Linked to Higher Autism Risk
- The Wall Street Journal: Study Finds Link Between Induced Labor and Autism Diagnosis
- Forbes: Autism Risk And Labor Induction: Is There A Link?
As is often the case, the “big news” headlines and associated media stories attract a lot of attention, but one must look at the study to really assess what the real information has to say. When someone only reads the short media blasts, the reader does not get the full information and bases an opinion on only the headline or sound bite. This is a type of cognitive distortion which is commonly known as jumping to conclusions. When doing so, the most common conclusion will be a negative one.
The topic of Autism is a hot button issue. These headlines are specifically designed to garner a quick reaction from the reader. I was interested in taking a more thorough look at the study discussed, and want to share it with Science & Sensibility readers.
Gregory, et. al. acknowledge that there are both genetic predispositions and environmental factors linked to autism. They choose to look at one environmental factor, labor induction and augmentation. The team looked at 625,000 births in North Carolina. After controlling for other factors, such as congenital abnormalities, multiples, maternal education, marital status, maternal smoking, parity and mode of delivery, the group of infants was narrowed down to those who were comparable using the North Carolina Detailed Birth Record (NCDBR). These infants were followed through their school years using the North Carolina Education Research Data Center (NCERDC) containing the indicator for exceptionalities, designation autism.
After comparing the data, there does appear to be a correlation between autism and induction/augmentation.
Approximately 1.3% and 0.4% of male and female children were diagnosed as having autism, respectively. Amon g both sexes, the percentage of induced or augmented mothers was higher among children with autism compared with non cases.
Moreover, children with autism were more likely to have a birth characterized by fetal distress or meconium.
But what correlates to what? Is the fetal distress the cause of autism, the meconium? Is it the induction? Is the fetal distress due to the induction, or for some other reason? Is the fetal distress due to pre-existing autism? Correlation is not causation.
Compared with children whose mothers were neither induced nor augmented during labor, children born to mothers who were either induced and augmented, induced only, or augmented only experienced increased odds of autism. Autism diagnosis differentially associated with induction/augmentation by sex, whereby a stronger association was observed among male children.
To our knowledge, this is the first large scale study to address the relationships among birth induction/augmentation and autism. This study also confirmed previously documented risk factors for autism such as advanced maternal age and maternal education, parity, and singleton birth (as reviewed by Gardener et al3 and Guinchat et al13).
The more risk factors mother and baby have, the higher the rates of autism in the baby. However, “We controlled for each of these variables and found that labor inductions and augmentation continued to be independently associated with ASD in offspring.”
The authors speculate about exogenous oxytocin and its effect on the fetal brain. “Exposure to exogenous oxytocin during induction/augmentation may have a functional effect through, as yet, unidentified genetic or epigenetic factors.”
Gregory, et al. is not the first study to look at the relationship between oxytocin and autism. There are a number of studies which examine the relationships between oxytocin and vasopressin and autism in both boys and girls. The hypothesis that artificial oxytocin, administered during labor, has a negative affect on the fetus’ brain has been around for some time – this is Hollander’s theory. A 2004 review of the literature by Wahl, suggests at a molecular level (in animals) that Hollander may be on the right track, but systematic research is needed. Gregory, et al. is the beginning of that systematic research.
Is perinatal brain injury, whether through induction, augmentation, hypoxia or other issues, a cause of autism? Maybe?
We do know that there are side effects to everything we do during labor, from induction to augmentation, assisted delivery and cesarean sections. It’s not time to throw the baby out with the bathwater and give up on labor interventions. It may be a question of risk mitigation, or choosing one set of risks over another. There is no easy or straightforward answer as to whether or not we do more harm with a medical intervention than do we help. Each mother, each baby and each labor must be addressed on an individual case by case basis to determine the cost/benefit of each potential intervention. A physiologic approach to birth generally has better outcomes and avoids iatrogenic complications.
So, from Gregory, et al. we so know that there is an increased risk of autism, especially in boys with the use of labor induction and augmentation. Many pieces of the puzzle are still missing, however. It is still too early to determine if this is correlation or causation.
“Our results are not sufficient to suggest altering the standard of care regarding induction or augmentation; our results do suggest that additional research is warranted.”
In other words, it’s far too soon to change how we treat women when it comes to induction and augmentation. We need to go deeper, and study further the effects of artificial oxytocin on the fetal brain.
As an educator, and as a mother to a child on the spectrum, I will address this in my classes in the same manner I always have. I give parents the best evidence-based information, tell them to use their BRAINS questions and let them go with what their hearts, and their heads, tell them is best for mother and baby. As of now, the evidence isn’t strong enough to point the finger at induction and augmentation. It is, in my opinion, strong enough to encourage our parents to ask more questions with regards to the effects of induction and augmentation on their babies.
Have you discussed this research with your students? Have any questions been raised? Do you discuss these research findings when you discuss benefits and risks to labor induction and augmentation? Please share your thoughts in the comments section of our blog. – SM
Carter CS. Sex differences in oxytocin and vasopressin: implications for autism spectrum disorders? Behav Brain Res. 2007;176(1):
Gregory SG, et al “Association of autism with induced or augmented childbirth in North Carolina birth record (1990-1998) and education research (1997-2007) databases JAMA Pediatr 2013; DOI: 10.1001/jamapediatrics.2013.2904.
Wahl RU, “Could oxytocin administration during labor contribute to autism and related behavioral disorders?–A look at the literature.” Med Hypothesis, Initiative for Molecular Studies in Autism (IMSA) 2004.
Gardener H, Spiegelman D, Buka SL. Prenatal risk factors for autism: comprehensive meta-analysis. Br J Psychiatry. 2009;195(1):7-14.
Gardener H, Spiegelman D, Buka SL. Perinataland neonatal risk factors for autism: a comprehensive meta-analysis. Pediatrics. 2011;128(2):344-355.
Gregory SG, Connelly JJ, Towers AJ, et al. Genomic and epigenetic evidence for oxytocin receptor deficiency in autism. BMC Med. 2009;7:62.