Caesarean section, or c-section, is a common mode of delivery in the United States, accounting for approximately 33 percent of births, reports the Centers for Disease Control and Prevention. The rise in the national rate of c-section births can be attributed to the fact that more and more healthy women are asking for the mode of delivery without a medical necessity. Doctors commonly suggest a c-section for expecting mothers when a vaginal birth is not an option or can put the mother’s and baby’s health at serious risk. Unlike a natural birth, a c-section is performed by an incision that is made from the mother’s abdomen above the pubic area, followed by an incision into the uterus where the baby is pulled out gently, says the University of Maryland Medical Center. This mode of delivery, however, directly impacts an infant’s developing immune system at birth because the gastrointestinal tract of a fetus is colonized by the bacteria from the mother and the surrounding environment instantaneously. This exposure to environmental bacteria in c-section delivery can determine whether the infant will be at risk for allergies.

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C-Section And Gut Bacteria

Babies that are delivered by c-section do not acquire a mother’s vaginal, intestinal, and perianal bacteria at birth. Instead, c-section babies obtain bacteria from the hospital environment and don't get any bacteria from one of the major gut bacteria groups, Bacteroidetes, that is essential for preparing an infant’s immune system to healthily respond to environmental triggers. Findings published in the journal Gut show that infants delivered by c-section have lower levels of healthy gut bacteria during their first two years of life, compared to infants delivered by vaginal birth, increasing their risk of developing allergies in their lifetime.

"Microbial colonization of the infant gut gastrointestinal tract is important for the postnatal development of the immune system," wrote the researchers in their report. In the study, nine out of 24 babies who were delivered by c-section showed significantly lower levels of chemicals vital to preventing the onset of allergies. Th1 and Th2 are immune system chemicals that are affiliated with chemokines — proteins secreted by cells. The babies delivered by c-section were found to have a chemical imbalance between Th1 — which is responsible for preventing the development of allergies — and Th2, which is responsible for the development of allergies.

"Infants born by vaginal delivery typically shared more bacterial species with their own mother than with other mothers, while this could not be shown for infants born by caesarian section,” said Anders Andersson and Maria Jenmalm, two of the study's authors, to Medical News Today. The gut bacteria that come from the birth canal are obtained by infants delivered by vaginal birth, optimizing the health benefits of the microbiome.

For c-section babies, normal bacterial colonization may be delayed, as infants acquired Bacteroidetes a year after birth in the study. Bacteroidetes strongly impacts an infant’s developing immune system as it enhances T-cell activity and maintains the chemical balance between Th1 and Th2 chemokines.

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Reasons For A C-Section

The mode of delivery isn’t always in the hands of an expecting mother. Medical necessities may require a mother to get a c-section although she may wish do to a natural birth. According to Mayo Clinic, here are a few reasons why your doctor may recommend a c-section:

· Your baby isn't getting enough oxygen. If your health care provider is concerned about your baby's oxygen supply or changes in your baby's heartbeat, a c-section might be the best option.

· You have a health concern. Your health care provider might suggest a c-section if you have a medical condition that could make labor dangerous, such as unstable heart disease or high blood pressure. In other cases, a c-section might be recommended if you have an infection, such as genital herpes, that could be passed onto your baby during vaginal delivery.

· Your baby has a health concern. A c-section is sometimes safer for babies who have certain developmental conditions, such as excess fluid in the brain (hydrocephalus).

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For more reasons why your doctor may suggest a c-section delivery, click here.