Normal delivery, also known as vaginal delivery, is the most common way for babies to be born. During a normal delivery, the baby passes through the birth canal and out through the vagina. This is different from a Cesarean section (C-section) where the baby is delivered through surgically making an incision in the mother’s abdomen and uterus. Many parents wonder if the process of a normal delivery can increase the chances of their baby developing autism later in life. This article will examine the evidence around this question.
What is autism?
Autism spectrum disorder (ASD) is a developmental disability that affects how a person communicates with and relates to other people, and how they experience the world around them. The main areas affected in autism are:
– Social skills – Difficulty with social interactions and building relationships. This includes challenges with nonverbal communication like eye contact and facial expressions.
– Communication – Delayed or absent speech, challenges expressing needs and desires through words, repetitive use of language.
– Restricted interests – Highly focused interests, affinity for routine and sameness, repetitive behaviors.
– Sensory issues – Hypersensitivity or undersensitivity to sound, touch, taste, smells, light, etc.
The symptoms of autism can range from mild to quite severe, which is why it is called a “spectrum” disorder. Autism affects people of all races, ethnicities and socioeconomic backgrounds. It is estimated to affect around 1 in 44 children today. Autism is believed to be caused by a combination of genetic and environmental factors that impact early brain development. There is no medical test for autism. It is diagnosed based on observed behavior and developmental history.
Does the method of childbirth affect autism risk?
There has been some research looking at whether the method of delivery could influence a child’s chances of developing autism later on. Specifically, some scientists have hypothesized that the compressions and stresses on the infant’s brain during vaginal delivery may contribute to altered brain development or small injuries that could make a child more susceptible to autism.
However, most current research has found no significant link between delivery method and future autism risk. For example, a 2015 study published in JAMA Psychiatry looked at over 1.1 million births in Sweden and found no difference in autism rates between siblings born vaginally versus by C-section from the same mother. Several other large studies comparing autism prevalence in C-section babies versus vaginal delivery babies have had similar findings.
Based on the current body of evidence, the method of delivery does not appear to directly cause autism or substantially alter autism risk on its own. Both vaginal birth and C-section come with pros and cons, but parents should not feel they need to choose one over the other solely due to autism concerns.
Risk factors for autism
Although delivery method does not seem directly linked to autism, research has identified a number of other factors that do appear to increase a child’s risk of developing autism:
Genetics
Autism has a strong hereditary component. Having one child with autism increases the odds of having a second child on the spectrum. Specific gene mutations and variants like changes to the CHD8 gene have also been associated with higher autism risk.
Parental age
Advanced parental age at conception has been linked to increased autism risk. Children born to fathers over age 50 and mothers over age 40 have higher odds of developing autism compared to those with younger parents. The reasons are unclear but may involve age-related changes in sperm, eggs and placental function.
Premature birth
Babies born prematurely (before 37 weeks gestation) appear to have a greater risk of autism compared to full-term infants. The stresses of early birth and more medical interventions required may negatively impact neurodevelopment.
Pregnancy complications
Certain prenatal and pregnancy conditions in the mother like gestational diabetes, bleeding, hypertension, and infection can increase autism risk for the baby. These may cause inflammation, oxygen deprivation or other impacts on the developing fetal brain.
Medications during pregnancy
Some studies link medications like antidepressants, epilepsy drugs, and thalidomide (no longer prescribed) used during pregnancy to heightened autism risk. More research is needed as findings have been mixed.
Does labor and delivery trauma increase risk?
While autism does not appear directly linked to routine vaginal delivery, some parents have concerns about whether complications or trauma during labor and delivery could contribute to their child developing autism later on.
Some potential types of delivery trauma include:
– Cord prolapse – When the umbilical cord slips through the cervix before the baby, cutting off blood flow.
– Shoulder dystocia – When the baby’s shoulder gets stuck during delivery.
– Use of forceps or vacuum extraction during assisted vaginal delivery.
– Intracranial hemorrhage (bleeding in baby’s brain) from pressure changes.
– Lack of oxygen to the baby during a long or difficult labor.
– Head or brain injury from pressure through the birth canal.
There is limited evidence directly tying these types of birth injuries to increased autism rates. A few small studies have found higher rates of autism in infants who experienced hypoxia (lack of oxygen) at birth or bleeding in the ventricles of the brain right after delivery. But more research is needed to determine if these complications directly heighten autism risk or are just associated with it.
In general, experts believe that most children can withstand and recover from the typical stresses of labor without long term harm. The risks associated with emergency C-section are also low. Overall, parents should be reassured that a difficult delivery or minimal birth trauma is very unlikely to singularly “cause” their child’s autism if they are later diagnosed. But discussing any significant delivery complications with your pediatrician is recommended.
Does C-section reduce autism risk?
Given the theoretical risks of labor trauma, some parents have wondered if elective C-section could help prevent autism in children predisposed to it. For example, choosing to deliver via C-section if they already have one child with autism.
However, there is currently no evidence that elective C-section reduces the risk of autism. As mentioned previously, studies comparing autism rates in vaginal versus C-section deliveries show no difference between the groups.
Due to the major abdominal surgery involved, elective C-section also comes with more risks for the mother such as bleeding, infection, blood clots, and negative reactions to anesthesia. Recovery is longer and more difficult compared to vaginal delivery. C-section also poses certain risks for the baby’s health.
As a result, most experts do not recommend elective C-section solely to try to reduce theoretical autism risks. The established risks of C-section usually outweigh the unproven potential benefits.
Can the type of vaginal delivery impact risk?
While vaginal delivery as a whole does not appear linked to autism, some parents also question if the type of vaginal delivery may affect risk. For example, forceps and vacuum assisted deliveries compared to spontaneous vaginal birth.
A few studies have found a slightly higher rate of autism diagnosis in children delivered with forceps versus other methods. One researchers theorized that forceps assistance may apply more pressure and stress to an infant’s brain than spontaneous vaginal delivery.
However, other studies have shown no difference in autism rates between assisted and unassisted vaginal delivery. More research is needed to determine if the type of vaginal delivery influences risk in any way.
Overall, parents should keep in mind that that autism has complex causes. Any potential effects from delivery method would likely be quite small. Focusing too much on the type of birth misses the bigger picture of genetic and environmental factors that shape neurodevelopment.
Measures to reduce autism risk
While much is still unknown about the causes of autism, experts recommend the following steps during pregnancy and infant care to help reduce risks:
– Seeing a doctor early in pregnancy to closely monitor health issues.
– Taking prenatal vitamins with folic acid before and during pregnancy.
– Avoiding smoking, alcohol and illegal drugs during pregnancy.
– Testing for issues like gestational diabetes and high blood pressure.
– Treating any infections or illness promptly during pregnancy.
– Ensuring any prescription medications taken during pregnancy are safe.
– Delivering baby at term whenever possible (37-40 weeks gestation).
– Carefully monitoring baby for jaundice, low blood sugar, lack of oxygen and other newborn health issues.
– Supporting overall brain development in infancy with love, touch, reading and communication.
– Ensuring baby gets needed immunizations but spaciously (no more than 1-2 shots at a time).
– Breastfeeding baby for at least 6 months whenever possible.
– Limiting baby’s exposures to environmental toxins in food, water, air, and products whenever possible.
Conclusion
Based on current medical evidence, undergoing a normal vaginal delivery does not directly increase the risk of a child developing autism later in childhood. The potential stresses of labor and delivery do not singularly cause autism. Overall, autism risk appears connected to a complex interaction of genetic susceptibilities and environmental exposures in the womb and after birth. While more research on the role of delivery method is warranted, parents should not feel they must choose C-section solely to avoid autism. Vaginal birth and cesarean birth both come with a mix of pros and cons to weigh with your obstetrician. Maintaining good prenatal and postnatal care practices is most important for giving babies the best start in life, whether they are born vaginally or via C-section.
