Caesarean Birth Vs Normal Birth: Effects on Gut Health of the Child

The decision for caesarean birth is never an easy one. However, if you are opting for elective caesarean section, it is important to understand the implications on the health of the mother and the child. In this article, we talk about the increasing evidence of a C-section on long term gut health of the child and what you can do about it.

The mode of delivery—caesarean section (CS) or vaginal delivery—can have significant long-term effects on a child's health, influencing the gut microbiome, psychological and physical parameters, and the risk of certain diseases. For some it may not be a choice where the option of surgery is to save the life of the mother or the child, but where there is a choice, it is important to take the following into consideration.

Let us be very clear, a CS is a medical decision based on the priority and medical need of the mother and child’s health and outcome. There are many situations where a planned CS may be done based on the position of the baby or foreseeable risks. Some situations warrant an emergency CS which is a life saving measure for the mother/child or both.

1. Elective Caesarean Section (Elective CS):

It is a planned surgical delivery of the baby, scheduled in advance, usually before the onset of labor. It is usually performed after 38 weeks of gestation or later to ensure that the baby is mature enough. Since it is not urgent and well planned, it allows time for preparation (medical, logistical, psychological). An elective CS usually has lower risks than emergency CS if properly planned and done in a well-planned manner in the hands of the expert.

There could be several reasons for an elective CS:

• Previous caesarean delivery- If the mother has had previous delivery/ies through a CS then the scar tissue area may still be fragile and therefore may stand a chance of rupture. In these situations, the Obstetrician discusses and plans an elective CS.
• Breech or abnormal presentation- Normally a baby would come headfirst, in some situations, the shoulder, buttocks or legs may be the part that’s facing below instead of the head, these positions are considered abnormal and may cause injuries while delivery. Therefore, they warrant a CS.
• Maternal request (without medical urgency)- Sometimes, when the mother is extremely apprehensive or has some constraints 
• Predicted large baby (macrosomia)- During the course of prenatal ultrasounds, sometimes especially in Diabetic mothers, a larger size baby may be detected. This may cause difficulty in a normal vaginal delivery and therefore a CS becomes a safer option. 
• Maternal health conditions (like heart disease) where labour is risky so a quicker delivery via CS with minimal blood loss is helpful.
• Placenta previa detected earlier but stable- Sometimes the placenta is placed abnormally and may be blocking the opening from where the baby needs to be delivered. In some cases, it is partial, and it may be safer to opt for a CS.

2. Emergency Caesarean Section (Emergency CS):

It is an unplanned surgical delivery done when there are sudden complications that pose risks to the mother or baby. It is done urgently or immediately, without paying much attention to the gestational age (number of weeks of pregnancy), depending on the situation. It is of high priority, often lifesaving, with minimal time for preparation. It usually comes with a higher risk due to urgency and potential instability of the mother or baby.

Some reasons for an emergency CS are:

• Foetal distress (abnormal heart rate, oxygen deprivation)- When the doctor detects an abnormal heart rate or signs of distress in the baby then and emergency CS is opted for to have a safe outcome for mother and child.
• Failed labour progression- Sometimes despite all efforts like using medications, gels etc., the labour does not progress and may pose a threat to the child. In such situations an emergency CS is the way forward.
• Uterine rupture- Though uncommon, sometimes, the wall of the uterus tears during labour and requires an urgent repair under direct visualization. 
• Cord prolapse- In some cases, the umbilical cord joining the placenta to the baby come out of the cervix before the baby does and then may become a potential source of infection and distress to the baby. In such cases and emergency CS is done.
• Severe bleeding (e.g., abruptio placentae)- Bleeding may cause additional burden on the hearts and increase chances of shock and heart failure and thus an emergency CS is warranted to save the life of the mother.
• Maternal complications (eclampsia, severe infection, etc.)- Sometimes the mother may have very high Blood pressure(eclampsia) or signs of a severe infection. Both situations may lead to unfavourable outcomes and thus an emergency CS helps reduce hospital stay and or saves the lives of the mother and child.

Impact on the Gut Microbiome

Infants born via vaginal delivery are exposed to their mother's vaginal and intestinal microbiota, this helps to develop favorable bacteria such as Lactobacillus and Bifidobacterium very early on in the baby’s gut. It is different for babies born through a CS as their gut is more likely to be inhabited by skin-associated and environmental bacteria, including Staphylococcus and Clostridium species. Why does this matter? Well, medical data and studies (Observational cohort studies and systematic reviews have consistently shown associations, not direct causation) suggest that there is a scientific Consensus that the link between CS birth and altered gut microbiota is strong and well-established and the link between altered microbiota and increased disease risk is moderate, with a growing body of supportive evidence, but still not definitive for causality) that the altered microbial colonization in the gut of neonates born through a CS have an increased risk of immune disorders such as asthma, allergies, type 1 diabetes, and celiac disease and metabolic disorders such as obesity and insulin resistance.

Physical Health Outcomes

Many studies have reviewed the association between the type of delivery method and long-term physical health outcomes:

• Obesity: Children born via CS have been found to have a higher risk of developing obesity in later life. A comprehensive review highlighted that CS delivery might be linked to an increased risk of being overweight or having obesity among children aged 2–5 years. A comprehensive meta-analysis published in PLOS ONE (2015) reported that children delivered by CS had approximately a 33% higher risk of becoming overweight or obese in childhood, adolescence, or early adulthood compared to those born vaginally. However, this association is correlational, not necessarily causal. While the biological plausibility exists—mainly due to differences in early gut microbiota composition—causation has not been definitively established. Several confounding factors such as maternal BMI, genetics, lifestyle, and feeding practices (e.g., breastfeeding) may also contribute to this increased risk) 
• Allergic Diseases: Medical evidence also suggests (strength of this evidence is moderate to strong, particularly in large-scale cohort studies and meta-analyses that consistently show an increased relative risk of asthma (approximately 20–30% higher) in CS-born children compared to those delivered vaginally) that babies born through a CS have a higher incidence of asthma and allergic conditions. The lack of exposure to maternal vaginal microbiota during birth is thought to influence the development of the immune system, potentially leading to these outcomes. Newborns delivered by C-section tend to have disease-causing microbes commonly found in hospitals (e.g. Enterococcus and Klebs) and lack strains of gut bacteria found in healthy children (e.g. Bacteroides species). Because it is known that gut microbiota is in close communication with the immune system, this difference in birth microbes may set the immune system up for later dysfunction.
• Nutritional Status: A study utilizing data from the National Family Health Survey in India found that children delivered by CS had higher rates of stunting, wasting, and underweight compared to those born vaginally. This association is not necessarily causal. There are numerous confounding factors that may influence both the mode of delivery and child nutrition outcomes, such as maternal health and nutrition, socioeconomic status, access to breastfeeding support, postnatal care and feeding practices, preterm births and medical complications prompting CS.

Psychological and Behavioral Outcomes

Research on the psychological and behavioral impacts of delivery mode is ongoing, with some studies indicating potential associations:

• Neurodevelopmental Disorders: Some studies have explored links between CS delivery and an increased risk of neurodevelopmental disorders, such as autism spectrum disorders and attention-deficit/hyperactivity disorder (ADHD). However, these associations require further investigation to establish causality.

Disease Risks

The mode of delivery has been associated with varying risks for certain diseases: 

• Autoimmune Diseases: There is evidence suggesting that children born via CS may have an increased risk of developing autoimmune diseases, such as type 1 diabetes. The hypothesis is that altered microbial exposure at birth may influence immune system development.
• Metabolic Conditions: Alterations in the gut microbiome due to CS delivery have been linked to metabolic conditions, including obesity and diabetes, later in life.

Is there an option to improve/restore the gut microbiome after a CS delivery?

Here are some measures that are being studied/evaluated to modify the gut microbiome:

• Probiotics: These are a variety of living microorganisms that, when taken in sufficient quantities, may improve the host's gut microbiota. Additionally, probiotics (of different strains) have been shown in some trials to prevent IgE-associated allergies till the age of five, specifically in caesarean-delivered newborns but not in all children.
• Maternal vaginal microbial transfer: Also referred to as "vaginal seeding" or "microbial bath," this technique involves swabbing newborns delivered via caesarean section with gauze containing microorganisms from the mother's vaginal canal as soon as possible. The safety of this technique is not fully established, and it is too early for widespread use, despite some studies showing that it is successful in returning the infant's gut microbiota to normal.
• Breastfeeding: Breast milk contains live bacteria and other substances that interact with the gut microbiota, making breastfeeding the gold standard for baby nutrition. When C-section babies are exclusively breastfed for approximately six months, their gut microbiota changes to resemble that of vaginally delivered babies. Exclusive breastfeeding for 4–6 months is one of the most practical and effective interventions to support gut health in CS-born infants. Even partial breastfeeding (combined with formula) is better than none, but exclusive breastfeeding has the strongest benefits. Several studies have shown that within 3 to 6 months, the microbial profile in exclusively breastfed CS-born infants begins to show increased diversity and abundance of beneficial bacteria, including Bacteroides and Bifidobacteria. A 2020 review in Frontiers in Microbiology highlighted that exclusive breastfeeding mitigates many of the microbial imbalances initially seen in CS-born infants.

This area is till grey and needs a lot more studies to standardize and develop these approaches.

What Actions Can Mothers and Families Take to ensure that the right decision is made?

1. Educate Yourself About Birth Options

• Families with expectant mothers should learn the difference between elective CS, emergency CS, and vaginal delivery. They should understand the short-term and long-term outcomes for mother and baby in each scenario (e.g., recovery time, microbiome, long term health effects etc.).

2. Prioritize Early and Regular Prenatal Care

• Early prenatal visits can help detect risk factors that may possibly lead to the decision of a CS. This gives them time to discuss and plan appropriately. A well-supported vaginal birth is often safest when there are no medical complications.

3. Support Natural Vaginal Birth When Safe

• Unless there is a clear medical indication, opting for vaginal birth is helpful in transferring healthy maternal microbiota to the baby, promoting easier initiation of breastfeeding and it also shortens the recovery time for the mother.

Key Questions to Ask Your OBGYN if you have been recommended a C-section:

1. Is there a medical reason for the recommendation of a C-section in my case?
2. Can I try for a vaginal birth after CS if I’ve had a prior CS?
3. What are the risks and benefits of vaginal vs. CS delivery in my case?
4. Will I be supported in immediate skin-to-skin and early breastfeeding after birth?
5. What is your hospital’s rate of CS for low-risk pregnancies?
6. Can we create a flexible birth plan that prioritizes natural birth but allows for CS if needed?

For more information on C-section, read https://www.patientsengage.com/conditions/questions-ask-surgery-part-2

Conclusion

Although caesarean sections are necessary and even lifesaving in some medical circumstances, there is growing evidence that they may have long-term effects on a child's health, influencing physical health metrics, the gut microbiota, and the likelihood of developing certain disorders. In order to ensure that caesarean sections are carried out only when medically necessary, Families may have a viable discussion with the doctor to understand the potential risks and the need for a CS pointing that it is in the best intertest of the mother and child and a necessity.

References

• Shao, Y., Forster, S. C., Tsaliki, E., et al. (2019). Stunted microbiota and increased pathogen colonization associated with caesarean birth. Nature, 574(7776), 117–121. DOI: 10.1038/s41586-019-1560-1
• Sevelsted, A., Stokholm, J., Bønnelykke, K., & Bisgaard, H. (2015). Cesarean section and chronic immune disorders. Pediatrics, 135(1), e92–e98. DOI: 10.1542/peds.2014-0596
• Mueller, N. T., Whyatt, R., Hoepner, L., et al. (2015). Prenatal exposure to antibiotics, cesarean section and risk of childhood obesity. International Journal of Obesity, 39(4), 665–670. DOI: 10.1038/ijo.2014.180
• Azad, M. B., Konya, T., Maughan, H., et al. (2013). Gut microbiota of healthy Canadian infants: profiles by mode of delivery and infant diet. Microbiome, 1(1), 19. DOI: 10.1186/2049-2618-1-19
• Thavagnanam, S., Fleming, J., Bromley, A., et al. (2008). A meta-analysis of the association between caesarean section and childhood asthma. Clinical and Experimental Allergy, 38(4), 629–633. DOI: 10.1111/j.1365-2222.2007.02780.x
• Blustein, J., Attina, T., Liu, M., et al. (2013). Association of caesarean delivery with child adiposity from age 6 weeks to 15 years. International Journal of Obesity, 37(7), 900–906. DOI: 10.1038/ijo.2013.49
• Curran, E. A., O’Neill, S. M., Cryan, J. F., et al. (2015). Research Review: Birth by caesarean section and development of autism spectrum disorder and attention-deficit/hyperactivity disorder: a systematic review and meta-analysis. Journal of Child Psychology and Psychiatry, 56(5), 500–508. DOI: 10.1111/jcpp.12351
• Cardwell, C. R., Stene, L. C., Joner, G., et al. (2008). Caesarean section is associated with an increased risk of childhood-onset type 1 diabetes mellitus: a meta-analysis of observational studies. Diabetologia, 51, 726–735. DOI: 10.1007/s00125-008-0941-z
• KC. “A Pediatrician’s Perspective on C-Section Births and the Gut Microbiome - International Scientific Association for Probiotics and Prebiotics (ISAPP).” Isappscience.org, 18 July 2022, isappscience.org/a-pediatricians-perspective-on-c-section-births-and-the-gut-microbiome/.
• Kim, Gyungcheon, et al. “Delayed Establishment of Gut Microbiota in Infants Delivered by Cesarean Section.” Frontiers in Microbiology, vol. 11, 11 Sept. 2020, https://doi.org/10.3389/fmicb.2020.02099.
• Korpela, Katri, et al. “Probiotic Supplementation Restores Normal Microbiota Composition and Function in Antibiotic-Treated and in Caesarean-Born Infants.” Microbiome, vol. 6, no. 1, 16 Oct. 2018, https://doi.org/10.1186/s40168-018-0567-4.