Let Them Eat Dirt. B. Brett Finlay
are now learning that there are significant health concerns associated with C-sections, including an increased risk of chronic disorders later in life, such as asthma, allergies, obesity, autism, IBD, and celiac disease. The elevated rates of these issues associated with C-sections hover around 20 percent for most of them. This is tremendously worrisome, considering that many countries have a C-section rate well above what the WHO recommends. Approximately 6.2 million unnecessary C-sections are performed around the world, with Brazil, China, the United States, Mexico, and Iran accounting for 75 percent of them. Brazil and China have an outright C-section epidemic; many hospitals in those countries deliver more than 85 percent of their babies surgically. The situation in Brazil has reached critical levels, as many women there have to give birth by C-section without the medical need for it, simply because of the shortage of hospital beds allotted for vaginal deliveries (see Brazilians Love C-sections, page 69).
The good news (kind of) is that it isn’t the procedure itself that causes these disorders. Rather, it’s something extremely important that does not occur during the few minutes it takes for a doctor to surgically remove a baby from the womb: the baby does not come in contact with his mother’s microbe-rich vagina and feces.
A Dirty Birth Is a Good Birth
A baby’s very first encounter with microbes most likely happens when his head comes out through his mother’s vagina. As previously mentioned, the vagina contains an extremely high number of microbes, so the seconds (or minutes) it takes for a child to exit the birth canal are enough to impregnate a newborn’s mouth, nose, eyes, and skin with many of them. It’s also very common for women to defecate during birth, especially during the pushing stage. Babies usually exit the birth canal with their mouths facing their mom’s anus, and it is now proposed that this position allows for additional exposure to maternal fecal microbes.
It makes total sense. The world is full of microbes, and all babies are going to get soaked with them immediately after birth, regardless of how they are born. Why not make sure that a baby gets coated in the microbes from which she will benefit most? Nature sees to it that the type of microbes first encountered by babies born vaginally are the ones that are going to aid in the digestion of milk, as well as contribute to the development of a baby’s immature immune system, and even protect them against infections. Vaginal secretions are packed with Lactobacillus, whereas another milk-digesting bacteria known as Bifidobacterium come from feces. You’ve probably heard these two types of bacteria mentioned in yogurt advertisements. It’s no coincidence that these bacteria are used in the dairy industry, as they’re experts at digesting or fermenting milk and are also associated with health benefits. Unknowingly, every mother seeds her baby with a special custom package of microbes that will best suit her baby’s needs. Babies instinctively seek their mother’s breast shortly after birth, and breast milk is exactly what these microbes need to flourish in the baby’s gut. This wonderful synchrony of biological events is a fine lesson in how nature works.
However, not every birth ensures the passage of beneficial microbes to newborns. As discussed in chapter 3, if the vaginal microbiota is unbalanced (low amounts of Lactobacilli in vaginal secretions), or if a woman has tested positive for Group B streptococcus (GBS), a baby will not get the same kind of microbial bath from her mom. Given how important it is to receive those beneficial microbes at birth, it’s critical that women pay special attention to their vaginal microbiota in the weeks preceding birth. If there are any signs of a vaginal infection (itchiness, burning sensation during urination, or abnormal discharge), it’s recommended that the mother consult a doctor and follow treatment with oral and vaginal probiotics as appropriate. In fact, given the proven safety of probiotics during pregnancy, all expectant mothers should consider including probiotics in their diet, especially in the weeks preceding birth (see additional recommendations in chapter 3).
If one could view birth through a microscope, a C-section is drastically different than a vaginal delivery: their microbiota is remarkably dissimilar. Studies comparing the gut microbiota of newborns in the days and weeks following birth consistently show that babies born by C-section have lower numbers of Lactobacillus and Bifidobacterium, as well as divergences in several other bacteria. These babies are colonized by microbes often found on skin, soil, and other external surfaces, instead of vaginal and fecal microbes. Even more worrisome, some of these differences persist and can still be detected when children are seven years old, according to a 2014 Dutch study.
To better understand how different a C-section is in the context of microbes, lets trace a baby’s possible route of microbial exposure following a C-section. The brand-new bundle of joy goes from the doctor’s sterile gloved hands to a table or a scale where he’s touched with medical utensils and cloths. He may also brush someone’s lab coat or hand in the process. If all is well, minutes later the baby is brought to his parents, and they can finally touch and kiss him, providing skin and mouth contact. Very often the baby is not allowed to breastfeed until his mother has started to recover from the anesthesia, which takes hours in most cases (although a few hospitals are now allowing this right after delivery). During this period, the baby will likely be wiped clean, warmly bundled in a clean hospital blanket, and placed in a cot, heated by a lamp, where he is offered warm (sterile) formula. During all this, the baby is exposed to the air, which has many microbes, but they are very different from mom’s microbes, the ones humans are adapted to get exposed to at birth. It can take up to two hours before the baby is returned to his mother, when he can finally try breastfeeding for the first time.
Seeding Hope for the Future
Clearly, a baby born via C-section surely misses out on something crucial: that first splash of mom’s microbes. But rather than judging mothers who have decided to give birth this way, whether by choice or due to medical necessity, we need to look at what can be done to make C-sections a more microbiota-friendly choice.
How can one restore a baby’s microbiota following a C-section? If you think about it, the way vaginally born babies are exposed to microbes is very simple: they come in contact with vaginal secretions. Why not inoculate a baby born by C-section with mom’s vaginal secretions shortly after birth? Such procedures, called “seeding,” are currently being used and tested in several hospitals around the world, and have been gaining an increasing amount of attention.
Veronica, a thirty-three-year-old mom from Edmonton, Canada, had to schedule a C-section some weeks prior to her due date because her baby was in breech position. However, she was aware of the importance of imparting her microbiota to her baby during vaginal birth and decided to talk to her midwife about this. Her midwife came up with a plan. She inserted a piece of sterile gauze into Veronica’s vagina while she was waiting to be taken to the operating room. Minutes before her C-section, her midwife removed the gauze and placed it in a sterile glass container. Right after their baby girl was born, Veronica’s husband took the gauze with gloved hands and swabbed it inside the baby’s mouth and on her skin. Veronica also swabbed her own nipples, with the hope that the infant would take in even more vaginal microbes while breastfeeding.
As far-fetched as this method may sound, Veronica is part of a growing trend of moms and health practitioners who are trying it. Not only does it make scientific sense, but there’s also scientific evidence backing up its effectiveness. Dr. Maria Dominguez-Bello, a scientist at NYU and a leading expert in the field of microbiota studies, has focused her attention on the development of early microbiota. She recently conducted a study involving eighteen births, in which babies born by C-section were “seeded” with mom’s vaginal secretions and placed on mom’s chest. Her team found that this process resulted in the microbiota of “seeded” babies becoming much more similar to that of a baby born vaginally. “While not equivalent to a baby born vaginally, there is some important restoration happening,” she says. It’s still unknown whether this simple procedure will reduce a baby’s risk of suffering a chronic illness later in life. Her research group will follow up with these children in the years to come. Additionally, her group is working on conducting a much larger study that can provide sufficient evidence in terms of the safety of this practice. In the meantime, there’s a compelling argument that women planning to have a C-section