What happens to your child’s immune system after c-section delivery?

C-section or vaginal birth—which is right for you?

Everyone has the same end goal when it comes to giving birth—that child is born safely. But how we plan to do that can differ hugely from person to person. Sometimes the type of delivery comes down to individual choice and other times, it’s down to medical necessity. And of course, sometimes even the best-laid birth plans change. Cesarean sections, or c-sections, now make up 21% of births around the world—that’s nearly double the rate since 2000. In some countries this rise is due to advancements in life-saving medical care and in others, it’s down to an increase in planned or elective c-sections.

But did you know that the way your child enters the world can affect her immunity? How does a child's immune system work?

During your last trimester of pregnancy, antibodies are passed from mom to child through the placenta, giving your little one some protection when she is born. This passive immunity—where the child has been given antibodies rather than making them herself— starts to decrease in the first few weeks and months of life. The process of building up active immunity starts during birth, when the child leaves the sterile womb to meet mom for the first time and picks up friendly bacteria along the way. These then colonize—or settle in—child’s gut, training her immune system to identify unfriendly microbes known as pathogens, so she can fight off infections. When is a child’s immune system fully developed? Every time your little one is exposed to a virus or germ, she will produce her own antibodies, but it takes several months for a child's immune system to mature.

We are 57% bugs!

More than half of your child’s body—and yours for that matter—is made up of microbes such as bacteria, viruses, and fungi. The rest—43%—is made up of human cells, meaning we are more bugs than humans! Most of these bugs, or microbes, are found in the gut and are known as gut microbiota or gut flora. Together, these gut microbiota, and the human cells live in an ecosystem called the gut microbiome. A healthy, balanced gut microbiome is linked to our immune system’s ability to fight infections and diseases and is important for our long-term health.

C-section or vaginal birth—how does delivery affect child immunity?

Vaginal birth

Research has shown that vaginally born children got most of their early bacteria from their mom. By taking samples from child's diapers, scientists were able to see that those born vaginally had friendly bacteria like bifidobacteria in their poop, showing that their gut microbiome had been colonized in. Previous studies had suggested that this could be due to vaginal bacteria being swallowed by the child on her way down the birth canal. However, more recent studies have discovered that it is actually due to child acquiring mom’s gut bacteria, having come into contact with her feces during labor!

C-section birth

Studies have shown that children born by c-section have vastly different microbiomes to those born vaginally, with fewer friendly gut bacteria at an early age. One reason for this is that they haven’t come into contact with the same microbes from their mom that they would do during a vaginal birth. Another is that they may have received a dose of antibiotics via the placenta if mom was given this before the c-section. Their children were also found to have higher levels of pathogenic, or unfriendly, hospital bacteria living in their guts. So, if you’re wondering, “do c section children have weaker immune systems?” The answer in general is yes—although the difference in their gut microbiomes normally evens out by age one, c-section-born children are more likely to develop allergies and other health conditions later in life. For example, some studies showed they are at least 20% more likely to have asthma or hay fever, as well as 23% more likely to develop type 1 diabetes in childhood, and nearly 60% more likely to be obese as young adults.

Ways to boost child’s immune system after c-section

Sometimes having a c-section is the best option for mom and child so you shouldn’t be put off having one if this is what your healthcare provider (HCP) has advised. If you are worried about your child’s immune system after c-section, there are things you can do to help.

1. Pass on your antibodies to your children

You might have heard of antibodies in maternal milk, but what do these do? Think of them like superpowers that extend your child’s passive immunity and help her to fight off infections. Maternal milk is also rich in bioactive compounds called HMO (human milk oligosaccharides). These feed the friendly bacteria and ward off the unfriendly bugs in your child’s gut, helping her developing immune system to function properly. Additionally, the World Health Organization recommends exclusive breastfeeding for the first six months of life followed by the introduction of adequate nutritious complementary foods, along with continued breastfeeding up to two years of age.

2. Worried about antibiotics and gut health? Consider probiotics

Antibiotics are used to treat and prevent certain infections caused by bacteria and at times may be essential for both you and child—they are often offered to women before having a c-section. However, they have also been shown to disturb a child’s gut microbiome—either when given directly or when passed through the mom—so speak to your HCP about the pros and cons of taking them and if any are avoidable. In any case, you may want to consider probiotics—for you or for child—to help rebalance your little one’s gut flora and encourage the development of her child immune system after c-section.

3. Follow your HCP’s child immunization schedule

It’s important to stick to your HCP’s child immunization schedule to ensure she’s protected from conditions such as whooping cough and measles. The first jabs will normally be given when your child is 8 weeks old.

4. Improve child’s microbiome with a pet

The environment you bring your child home to is important and, you may be relieved to hear that you don’t have to keep everything squeaky clean—in fact a few mucky paw prints and pet hairs can be a good thing! Research has shown that the microbiomes of toddlers are more diverse if they live with a pet and that households with dogs have lower rates of asthma. This has been put down to animals like dogs bringing microbes in from outside that are helpful in promoting Childs immune systems. Good news for you, child, and your furry friend!

What is vaginal seeding, and does it work?

Vaginal seeding is where a mom rubs her vaginal mucus on the face and mouth of her child after a c-section. It has become a trend in recent years in the hope of passing on friendly bacteria from the vagina that c-section-born children may have missed out on from not having travelled down the birth canal. However, studies have shown that children who were born vaginally have no more vaginal bacteria in their guts than children who were born via c- section. Researchers have therefore advised against vaginal seeding as not only is there no evidence of benefit, but it also puts children at risk of being exposed to unfriendly bacteria, such as Group B strep. Although normally harmless to adults, Group B strep, which lives in the vagina or rectum in a quarter of pregnant women, can cause serious problems if it spreads to the child. Breakthrough science: What is a maternal fecal microbiota transplant and how could it help a child?

A maternal fecal microbiota transplant (FMT) is when you transfer bugs from mom’s feces to her child. A small, preliminary study has shown that this could be carried out to correct the child gut flora of those born by c-section. In the study, moms’ feces were mixed with their maternal milk and given to their child who was born by c-section. The child's poops were then compared with other children who were born by c-section but didn’t receive the FMT treatment, and those born vaginally. After just seven days, the FMT-treated child had a healthier gut microbiome that was similar to vaginally born child, and different from untreated c-section-born children. It’s early days yet, but these promising findings could mean that in the future children may be able to have their gut balance restored after a c-section, getting their immune systems off to the best start possible. As exciting as this is, it is not recommended that you try this out at home as fecal transplants need to be screened to ensure they are safe.

References

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https://www.washingtonpost.com/national/health-science/the-big-number--21-percent-of-child-are-born-by-c-section-nearly-double-the-rate-in-2000/2018/11/16/ae539bfe-e8ef-11e8-bbdb-72fdbf9d4fed_story.html (Accessed April 7, 2021)

Last revised: June, 2021