“Both inside and out, our bodies harbour a huge array of micro-organisms. While bacteria are the biggest players, we also host single-celled organisms known as archaea, as well as fungi, viruses and other microbes – including viruses that attack bacteria. Together these are dubbed the human microbiota. Your body’s microbiome is all the genes your microbiota contains, however colloquially the two terms are often used interchangeably.”
Microbe colonization starts early during human development. “The fetus does not reside in a sterile intrauterine environment and is exposed to commensal bacteria from the maternal gut/blood stream which crosses the placenta and enters the amniotic fluid. This intestinal exposure to colonizing bacteria continues at birth and during the first year of life and has a profound influence on lifelong health. Why is this important? Intestinal crosstalk with colonizing bacteria in the developing intestine affects the infant’s adaptation to extrauterine life (immune homeostasis) and provides protection against disease expression (allergy, autoimmune disease, obesity, etc.) later in life. Colonizing intestinal bacteria are critical to the normal development of host defense.”
Although some scientists doubt that microbial colonization starts during intrauterine life, it is commonly accepted that an extensive exposure to microbial communities of fecal, vaginal, skin and environmental origins occurs at birth, and that this event has a major impact on the colonization of the neonatal gut.
Now, results from a new study show that during a natural vaginal birth, specific bacteria from the mother’s gut are passed on to the baby and stimulate the baby’s immune responses. However, this transmission is impacted in children born by caesarean section. The study (Birth mode is associated with earliest strain-conferred gut microbiome functions and immunostimulatory potential) has been published in the scientific journal Nature Communications on November 30, 2018.
Paul Wilmes, senior author of the study, said in a press release: “We find specific bacterial substances that stimulate the immune system in vaginally born babies. In contrast, the immune stimulation in caesarean children is much lower either because the bacterial triggers are present at much lower levels or other bacterial substances hamper these initial immune reactions to happen.”
For the study, the researchers analyzed the structure and function of gut microbial communities in newborn babies and their mothers using metagenomic analysis—and comparing neonates delivered vaginally with those delivered through cesarean section. The study results show differences between the microbiomes of the vaginally delivered neonates and the microbiomes of the neonates delivered through cesarean section. The researchers found that in vaginally delivered babies several functional pathways are over-represented as compared to the neonates delivered through cesarean section. The lipopolysaccharide (LPS) biosynthesis is one of the over-represented functional pathways, and this over-representation appears to be the result of specific bacterial strains that are transmitted from mothers to neonates during vaginal delivery.
The researchers stimulated primary human immune cells with LPS isolated from early stool neonatal samples, and found higher levels of tumour necrosis factor (TNF-α) and interleukin 18 (IL-18) production in cells stimulated with stool samples from vaginally delivered neonates as compared to cells stimulated with stool samples from neonates delivered through cesarean section. Accordingly, the researchers observed higher levels of TNF-α and IL-18 in neonatal blood plasma from vaginally delivered babies.
The researchers conclude that cesarean section delivery disrupts mother-to-neonate transmission of specific microbial strains, thus affecting immune stimulation during a critical window for the priming of the neonatal immune system.
After reading this blog, I was amazed and gained a lot of knowledge. In the process of natural vaginal birth, the “human microbiota” of the mother’s intestines – the colonizing bacteria infects the baby and stimulates an immune response. Mother’s colonizing bacteria are important for the immune homeostasis and host defense of offspring, and protect them from disease expression.
Since the colonizing bacteria infect the baby and stimulate an immune response, I conclude that caesarean section is weaker in immunization and disease resistance than a normal baby. For a better understanding and verifying my view, I did a further explore on the relationship between microbial colonization in mother’s gut and neonatal immunization, I found a paper, Gut Microbiota Composition in Healthy Japanese Infants and Young Adults Born by C-Section. This is a review article and it explains the research findings on infant immunity and maternal colonizing bacteria over the years. the article supports the idea that the mother’s gut microbes in the blog stimulate the baby’s immunity, and points out that there is a big gap in the immunization And in the future repspects section of the article, the author pointed out the free growing worldwide prevalence of diabetes, obesity, and autoimmune and cardiometabolic diseases over the past 20 years may be related to the increase of C -section deliveries. My inference is confirmed by this article.
https://www.ncbi.nlm.nih.gov/pubmed/30041174
Of interest in the discussion in infant microbiota due to differing birth modes, is the impact of the diet. The article above did not focus on this area, however, it is extremely important. I can agree with your conclusion that c-sections are a “weaker” means of providing immunity, and this may be associated with the mother’s dietary profile. Diet is an important factor of pregnancy, both to sustain the pregnancy and offer the neonate a healthy life expectancy. The study linked below looks at the effect of maternal diet on infant microbiome 6-weeks post-delivery. The effect of maternal dairy intake was a key observation for infants delivered via c-section because they are more at-risk for dairy allergies compared to the vaginally delivered group. This is associated with a decrease in milk-digesting bacteria, like Lactobacillus. In essence they found three main clusters of gut microbes in infants and the effects of maternal diet on microbiome which differed by delivery mode.
https://www.ncbi.nlm.nih.gov/pubmed/29973274
After reading this post, I know that gut microbiota colonization occurs in parallel with the maturation of the immune system, and this intestinal exposure to colonizing bacteria continues at birth and during the first year of life and has a profound influence on lifelong health. It is interesting that the mode of delivery can as a factor to influence the microbial colonization of the infant and in turn its immune system maturation. And I was thinking if breast milk microbiota should also be considered as an important source of microorganisms to the infant microbiomes and as part of microbial tolerance and immune training in the child.
When I saw this research, results from this study show that breast milk microbiota and other milk molecular components likely help to educate the infant’s immune system. It promotes an adequate intestinal immune homeostasis that initially influences a shift from an intrauterine Th2 predominant to a Th1/Th2 balanced response and stimulation of T-regulatory cells by BM-specific microorganisms. Furthermore, some strains isolated from BM have shown an ability to modulate both natural and acquired immunity. As a result, breast milk plays an essential role, guiding a normal microbiome development in the infant through the transference of prebiotic compounds that support the colonization of beneficial bacteria and antimicrobial components that protect the infant against infections.
https://www.ncbi.nlm.nih.gov/pubmed/30018263
Prior to reading your comment, I too have come to the conclusion that children who are breastfed by their mother in the early development of their immune system will influence later child health outcomes including obesity and other related diseases. I also found it interesting that microbial colonization is introduced to the infant at birth through the placenta from the mother’s gut. With this knowledge, I formed an idea that questions the impact artificial feeding have on infant development. In a recent article, the authors theorize that a high nutrient diet in infancy negatively ‘programs’ the metabolic syndrome in the child by promoting growth acceleration. They found that high protein content of artificial baby milk compared to the low protein content in breastmilk is responsible for the increased growth rate and adiposity during the important, development period of formula-fed infants. However, breastfeeding induces lower insulin levels, which decreases fat storage and prevents extreme early adipocyte development. Thus, the importance of this article further proves the fundamental connection between mother to child contact and its impact on the development of the immune system we have today.
https://www.ncbi.nlm.nih.gov/pubmed/22946146
This article highlights one of the benefits an infant receives when birth happens vaginally. The one question I had while reading this article was what other ways in which infants can establish their normal flora that is related to how they were born. It is common knowledge that breastfeeding helps establish the normal flora of the gut of infants. In a Chinese study, the gut microbes of vaginally born and exclusive breastfeeding infants (VB) was compared to cesarean born infants who were exclusively breastfed and mix feed with a formula (CB and CM respectively). It was essentially found that the relative abundance of enterococcus and Faecalibacterium of CB was more similar to VB, which is the control group, than CM was to VB. This study highlights that even though delivery mode will change the abundance of microbes found within an infants gut, breastfeeding can partially restore those differences.
https://www.ncbi.nlm.nih.gov/pubmed/30972048
I found this research article exploring the diversity of infants’ microbiome from drinking mothers milk versus drinking donors milk. I agree with what you’ve said, but its important to note that not just any breast milk will do the job, it seems that infants microbiome diversity is higher when its from mom. So it makes you think, imagine what it would be like having an infant born via caesarean and also being fed donor milk, they would be at a disadvantage. I feel like this has a lot to do with the microbiome exposed to the fetus during development, so when fed mothers milk, containing familiar microbes that were exposed during development, the infants microbiome responds more effectively compared to donors milk, where new microbes that the infants body has not been exposed to might come off as foreign to the immune system.
https://www.ncbi.nlm.nih.gov/pubmed/30982856
I agree with you both! I think the presence of breastfeeding is an important factor contributing to microbiome diversity and development of the infant. I thought it would be interesting to look at a study directly comparing the immune systems of babies from the following groups:
1. cesarean section birth and presence of breastfeeding
2. cesarean section and absence of breastfeeding
3. vaginal delivery and presence of breastfeeding
4. vaginal delivery and absence of breastfeeding
And it looking up studies related to this, I came upon this study published in 2017. The authors of this study looked at groups of infants based on birth mode, breastfeeding status, as you both have mentioned, in addition to another variable: antibiotic exposure.
They found that the infants who were breastfed and born vaginally with the absence of antibiotic exposure 3 months post birth showed a significant increase in the abundance of lactate producers in their microbiome. Accordingly, the differences in bacterial species in the microbiome seem to be related not only to status of breastfeeding and mode of delivery, but also antibiotic exposure. I think the results of the study are important, because it shows that there are multiple confounding factors which can yield differences in microbiome diversity of infants.
https://www.ncbi.nlm.nih.gov/pubmed/29018787
This is an interesting question to ask and could lead to some exciting new discoveries that greatly affect the direction of treating newborns and premature babies. The suggestion that breast feeding can restore some of the disrupted development of the immune system has been supported by other articles. I previously read an article discussing how disrupted gastrointestinal microbiota development from caesarean section can lead to development of diseases like Type 1 diabetes, obesity, asthma, and even allergies. Another article related to breast feeding discussed some of its benefits in the immune system development. Breast milk contains immune-active molecules and shape mucosal immune response. Within the first month, it can affect some critical long term health. Research also revealed that breastfeeding can lead to lower incidents of diabetes and asthma. Although it has many beneficial components, it can also negatively affect mothers with autoimmune diseases. This is also another interesting topic to study in depth.
It seems that the development of the microbiome is not just reliant on the method of birth alone, but also during development based off of what microbial intestinal tract the mother has. This suggests that infants’ risks of acquiring certain diseases is pre-determined while still developing in the uterus. Birth is not the only way they obtain their microbiome, instead it takes an infant 2.5 years from birth to develop a stable microbiome, consisting of all sorts of metabolic reactions. This continues to develop until the early years of adult hood. The type of microbiome developed can even pre determine future health. If you really think about it, shielding your new born from bacteria and attempting to keep a sterile environment might be causing your infant more harm than good, since in development they are already predisposed to all sorts of microbes unlike the notion we as humans have that they develop in some sort of sterile environment.
https://www.ncbi.nlm.nih.gov/pubmed/30986482
The fact that cesarian newborns do not inherit their mothers’ bacterial biome is a problem that requires research to solve. Since cesarian sections are necessary to prevent injuries during childbirth, research has to be done to circumvent this issue. Tran N. et al researched the therapeutic effects of multispecies probiotics in healthy young adults (1) and found improvements in the overall health of the randomized participants. If this treatment could help the immunological response of new-borns, then cesarian section babies might become an overall safer form of giving birth.
Tran N., Zhebrak M., Yacoub C., Pelletier J., and Hawley D. The gut-brain relationship: Investigating the effect of multispecies probiotics on anxiety in a randomized placebo-controlled trial of healthy young adults. 2019;252:271-277. Introduction; p. 271.
Another treatment method that seems to show some promise for cesarean-delivered babies is simply through the introduction of vaginal microbes. Though this is a partial restoration it does give back some of the necessary microbes that the babies need to hopefully build their immune system. In the study, this is simply done through the pre-swabbing of vaginal fluids with a sterile swab that is then kept in a sterile environment until use. One to three minutes after the birth, the baby is then swabbed with the fluids. It was shown that though not all microbes were obtained, there was a significant increase from cesarean-birthed babies with vaginal swabbing to cesarean-birthed babies without swabbing.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5062956/
More and more women opt (or are made to) have a C-section. I think this plays a negative impact on the overall health of the child. As read in this article, children who are delivered vaginally have better immune responses due to preexposure to the mother’s microbiome. Since the mother transmits IgG via the placenta, the baby should be relatively fine developing immunity to anything the mother transmits. In the article attached, the scientists wrote that the main function of the intestinal tract is to prevent the invasion of host cells to pathogens. In the main article the authors described that when babies are born via C-section, they have a weakened response to pathogens. This makes me wonder if it’s ethical for hospitals to make women have C-sections if it means causing harm later in life to the developing infant. This seems to be the most defining moment in the child’s development that really determines the lifespan and development of a good functioning immune system.
https://www.ncbi.nlm.nih.gov/pubmed/27475754
This seems like a fair assessment. The more we know the more we can make a more well-educated decision about what is morally correct. I think it would be wrong in general to try to push a woman one way or another towards how she gives birth. I understand that with vaginal birth it can sometimes put the mother at more risk. So, I can understand the push as well. Perhaps we could be looking at a compromise to see what we get that is beneficial in a vaginal birth and see if it can’t be replicated. An article I read for my post talked of different factors that the woman did as she was pregnant, and after birth, that in turn effected the development of the microbiome of the child. I think using this information might be a step in the right direction in better understanding something that may help us develop this benefit to give to immunocompromised individuals in general.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4943946/
I believe there are other ways to enhance the immune system development of children who are born via C-section, as I was reading in some other comments, there are ways to introduce the mother’s vaginal microbes to the baby’s body even after birth with vaginal swabbing. I understand your concern about the importance of the complete development of the newborns immune systems, but there are sometimes other factors that come to play as well that favors C-section for both the mother and the baby. The article that I’ve found talks about the pros and cons of both vaginal birth and cesarean. A few pros of cesarean are reducing the risk of urinary and fecal incontinence and the stress, fear and pain of the labor that can have a positive effect on the overall health of the baby. Some more specific benefits for the baby include the lower risk of unexpected stillbirth and labor complications such as clinical chorioamnionitis, cord prolapse and abnormalities involving fetal heart rate. I believe if there are ways to still enhance the development of the baby’s immune system after birth, then the mother has to choose between C-section or vaginal birth.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC343856/
I never actually thought about how the mother’s microbiota comes to play in with the fetus’s development. It is obvious to think after reading the article that yes, of course, the fetus has to have a way of building their own microbiota up, and how the mother’s internal environment is the way to go. Moreover, it is astonishing how a decision such as which way to give birth, whether it be vaginally or through a caesarian section, can affect a child so immensely. When thinking about such birthing processes you really only think about how it may affect the mother post birth, and the way to choose is determined based on the safest route for the baby. It is incredible that even though this process the mother is also passing on critical microbes and immune system related information to the baby. In the study listed below, it was found that c-section births were associated with lower T-lymphocyte formations and other immune-related deficiencies. As we all know T-lymphocytes are a critical part of our adaptive immune system. It would seem that the best method to deliver would be vaginal unless it poses a risk to the baby.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5599043/
The mother’s gut microbial communities is important because of all the helpful microbes that reside in our guts. I learned about the gut microbe in my Nutritional Neuroscience class and one thing for sure– it is very influential with our health including our weight, immunity and even certain diseases. The mother’s daily activities such as diet and exercise will also have a great impact of the child’s immune system. I agree that mothers should be convinced to have vaginal births unless it risk their life or the child’s.
https://www.ncbi.nlm.nih.gov/pubmed/30353125
I also found this post and the articles mentioned extremely interesting because we often hear of the importance of breastfeeding, as my classmates have indicated, as a vital component for developing an infant’s immune system, but as these articles and post indicate, vaginal delivery is also an important factor for immune system development of neonates.
I also found it interesting that there are specific strains of bacteria, transferred from the mother to baby, which induce the overexpression of functional pathways such as LPS biosynthesis in the infant. Accordingly, it would be interesting to see if therapeutically there is a way to transfer these strains to neonates born via caesarean section and then see if the overexpression of the pathways would be the same and if the levels of TNF-alpha and IL-8 are similar in the plasma to those of neonates born vaginally, as well as looking at the incidence of allergy, type 1 diabetes, and obesity long-term.
In conducting my PubMed searches, I came upon the following article published by Stinson et al. in 2018. They mention the importance of breastfeeding for an infant’s microbiome development, stating that 27% of an infant’s gut microbiota is vertically derived from its mother’s milk and that breast milk contains bacteria and prebiotics, which can modify the infant microbiome. The authors also mention findings of current research, which has shown that infants born from cesarean section have altered feeding habits, including a delay in breastfeeding, a shorter duration of breastfeeding, sub-optimal breastfeeding behavior and a reduced volume of consumption within the first five days of life. Accordingly, it could be that it’s the feeding habits, rather than mode of delivery, which yield differences in the microbiome of the infant. This is supported by another finding mentioned in the review article; the differences in the microbiome between infants from cesarean sections and infants from vaginal births resolved after the introduction of solid foods. I think like many things, there is no one factor that can explain this phenomenon, as it is a combination of many factors.
Stinson et al. also mention “hygiene hypothesis” and have published their article to advise against vaginal seeding, which is the practice of swabbing an infant born via cesarean delivery with the mother’s vaginal fluids following birth. The authors argue that though studies have shown a correlation with cesarean delivery and an altered infant microbiome, no studies have confirmed causality between the two. Along with breastfeeding, they list other confounding factors such as maternal obesity, differences in study methodologies and a lack of appropriate controls. The authors argue that it is most likely the antibiotics given to the mother during cesarean sections, which result in the altered microbiome, rather than the lack of exposure to vaginal microbes. The authors recommend against vaginal seeding, stating more research needs to be conducted.
https://www.ncbi.nlm.nih.gov/pubmed/29780807
As an aspiring Obstetrician/Gynecology, this article was extremely interesting. I knew from my previous microbiology class that babies born vaginally had a similar microbiome to that of their mothers at birth, and babies born via C-section had a different microbiome than their mothers. Additionally, I came across a study that looks at the difference in microbiome of babies born in the hospital versus those born at home (some of whom were born via water birth). In this study a total of 35 infants, 21 born at the hospital and 14 born at home, were assessed. The fecal microbiota of infants born in the hospital had increased Enterobacteriaceae and Clostridium species, and decreased Bacteroides, Bifidobacterium and Ruminoccocus species compared to those born at home. These differences were previously associated with health outcomes since high Clostridium levels were associated with an increased risk of asthma, while low levels were associated with decreased risk of eczema and asthma. In addition to the changes in microbiota, infants born in the hospital had an increase in “fecal microbiota associated products” that induced pro-inflammatory gene expression. Thus, both the mode of delivery and location are important factors of child birth and should be continually explored.
https://www.ncbi.nlm.nih.gov/pubmed/30353125
I found it interesting that you mentioned that not only is the method of delivery important, but the location as well. After having my baby via c-section I wondered how this will affect his immune system. I found an article that studied how the environment of birth affected piglets. It found that the more sanitary the birthing location, the more negative the impact on the gut development. For piglets born indoors, their gut closure and development was delayed as the gut epithelium was disorganized. In order for the gut’s complete closure to occur maturation factors that are found in breast milk are needed. I find this interesting because there are women who have had C-sections and also choose not to breastfeed. So, now the infant is at a double loss, because it has not passed vaginally through the mother to stimulate immune response, but also is not able to receive maturation factors to speed up gut development. More research should be done in order to determine ways to create an environment where even if the infant has to be born via c-section, they can still have exposure to their mother’s vaginal microbes and their immune system can still be stimulated. I have learned that it is important to still continue breastfeeding my baby so that he can receive these maturation factors, as well as vaccinating to help strengthen his immune response.
https://www.ncbi.nlm.nih.gov/pubmed/22216092
Before reading you both’s comments on the vital role location plays on the child’s immune development, I never really considered that a sterile environment may be doing the child more harm than good. Obviously, there’s a necessity for a certain level of cleanliness, but you also hear all the time from mothers that it is good when you’re child gets sick so they can build up their immune system. Then, the question becomes “how early can my baby get sick to help build that immune system?” It sounds weird phrasing that way, but it is clear that their immune systems are still developing even right after birth. However, at what point has their immune system developed enough to be able to withstand common illnesses? In the article listed below about the evolution of the human immune system, there is no clear cut timeline about when a baby’s immune system is capable of fighting common diseases. This is mainly due to the variability from child to child and the weaning off of the mother’s immunity the child will have to go through before age 1. All in all, it does highly depend on the environment the child is exposed to and how much of it their body can withstand and keep up with.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4707740/
Contrary to popular beliefs, the fetus is capable of developing microbiota before the placenta is penetrated. These microbiota come from the maternal gut/blood stream. The importance of microbiota is one that no one can doubt but the methods in which they attain them is one I have never considered. Although caesarean sections have saved the lives of many mothers and newborns, this article reveals that it also has some harmful impacts on the immunity of the newborn. This birthing method has been shown to disrupt the development of gastrointestinal microbiota. In turn, this further affects the status of the newborns health and are associated with the development of diseases like obesity, Type 1 diabetes, asthma, and allergies. The article on Intervention strategies for cesarean section-induced alterations in the microbiota-gut-brain axis confirms this belief that the caesarean method of birth disrupts some early stage developments in the infant.
https://www.ncbi.nlm.nih.gov/pubmed/28379454
The fact that cesarian newborns do not inherit their mothers’ bacterial biome is a problem that requires research to solve. Since cesarian sections are necessary to prevent injuries during childbirth, research has to be done to circumvent this issue. Tran N. et al researched the therapeutic effects of multispecies probiotics in healthy young adults (1) and found improvements in the overall health of the randomized participants. If this treatment could help the immunological response of new-borns, then cesarian section babies might become an overall safer form of giving birth.
https://www.ncbi.nlm.nih.gov/pubmed/30991255
I find this research to be very interesting. I recently learned a lot about the microbiome in my microbiology lab. From what I gathered from this article, neonates who were born vaginally had better exposure to the mother’s microbiome, in turn helping build their own healthy microbiome. This puts an insightful view on what could be given to the growing fetus while the mother is still pregnant. And what is given at birth. From my experience, people are always trying to tell a pregnant woman what she should and shouldn’t eat. I read an article that suggested that they are not completely wrong. “The gut microbiota during pregnancy is influenced not only by internal cues, but also by environmental factors, primarily by diet” (PMC4943946). It also talks about how their microbiome may also be linked to how they are fed and how they are exposed to antibiotics. All of this can help expand what we know about our microbiome and how we acquire it and if certain things are linked to our immunity as adults.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4943946/
I’m a big proponent of a healthy diet- I believe it has the opportunity to prevent many severe diseases. The article below highlights the maternal diet because it has the opportunity to influence the child via vertical transmission. Pregnant women do face many limitations when carrying- however it is all for their benefits. A stool sample was received from 45 babies and a pre assessments from the mothers about their diets. The study focus on fruit and dairy (both beneficial) and lead to results of higher diverse bacteria clusters in the infant’s stool. It’s amazing how the delivery mode of birth plays such an important role for the child’s future immune system.
https://www.ncbi.nlm.nih.gov/pubmed/29973274
From what I understand about immunology and microbiology, I believe that it is quite intuitive to say that those babies born by a vaginal birth are far more likely to be exposed to more bacteria in the birthing process as opposed to those that were born during a cesarean section. This is due to the fact that a baby born by C-section is birthed in a highly sterile environment as to not cause both the mother and the baby any infections especially those that are nosocomial. However, what I did not know was the fact that the microbiome has an effect on obesity. A study published by Cindy D. Davis highlights this notion, that the intestinal microbiome is intrinsically linked to the development of obesity.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5082693/
To add to your comment on how birth via c-section can cause a change in the relative abundance of the gut microbiome and causing obesity, I found a study that relates C- section births and prebiotic diets. This study highlights the fact that not only do c-section births cause infants to have increased risks of chronic inflammatory diseases (leaky gut syndrome), but it was found that these inflammatory diseases were linked to the gut health. To better understand the correlation between gut health and inflammatory disease, this study used mice as model organisms. It was found that cesarean section delivered mice had reduced regulatory T cells compared to those born vaginally. In addition, it was also found that regulatory markers and macrophage markers were upregulated in c-section born mice. Essentially, a prebiotic diet could restore regulatory T cell counts and gene expression of immunological markers of the intestine. The results of this study show that with targeted shifts in diets of infants born by c-section, a restoration of their gut microbiome could lead them to mirror those of infants born by vaginal birth.
https://www.ncbi.nlm.nih.gov/pubmed/30487172
I have read the article and understand that there is a common understand that vaginal birth (VB) is more beneficial to the mother and the child than C-section birth (CB). One of the questions I had was about the timeline, specifically “when” does the bacteria from the mother is passed on to the fetus that jump starts their immunity?
This article provides a better understand about the “when” and “where” this event occurs, and even produces a hypothesis about the “why” VB is said to be better. According to the experiment, infants born with CB that was planned, or before membrane rupture, are said to have reduced primary immunity after birth. Duly noted, that exposure to uterine fluid after rupture but a required CB will have similar microbiota in the infant after birth as a VB although it may take longer for the immune system to develop. This poses the questions if the mandatory application of antibacterial medications during surgery leads to destruction/reduction of the beneficial microbes and if so, is there a way to reduce the exposure of antibiotics without harming the mother and her child. Furthermore, the article also claims that mother that went through CB were slower to breastfeed their children, which was also noted important to start/modify the initial microbiota within the infants.
After presenting these facts, the author signifies the importance of further experiments to extract valuable details and specificity needed to improve the understand of the pros and cons of CB, which will allow for improved lifestyle of newborns and their mothers.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3110651/
Articles like this are what makes biology exciting for me. I had never considered that babies receive a strengthened immune system by going through vaginal birth. And now, I have this entirely new way of thinking about childbirth, the implications it will have on the child’s life, and a different cost-benefit analysis for a mother choosing a c-section. The initial post mentioned that there were lower cytokine levels in the stool samples for the c-section birthed baby, but I wanted to see if this translated into life-long implications. I found a paper that looked at the incidence rate of chronic immunological diseases in people born via cesarean section. Amazingly, they found seven diseases that are significantly higher in these individuals and they range from respiratory issues like asthma to tissue connectivity disorders to bowel diseases. It was noted that babies born by a c-section show lower levels of leukocytes during early development and have fewer stress hormones passed onto them by the mother. There was no causal link found between these immunologic diseases and the c-section, but the statistical significance makes the conversation worth having. To better understand the link between the two, another study that looks at the child’s environmental factors would be necessary.
https://www.ncbi.nlm.nih.gov/pubmed/25452656
I have found a website that links the causation of the abnormal wbc count. The authors indicate that the increased stress leads to increased leukocyte count in c-section babies that are responsible more for phagocytosis while the increased leukocytes for the vaginal birth were less active in phagocytosis. This differentiation is important because all the other articles were considering only the quantity of the cells, while this study actually looks at the functions and sequela of events that leads to the abnormal counts. For example, they looked at chemiluminescence (CL) that leads to more active phagocytosis. They also considered the effect that antibiotics, such as ampicillin would have in the CL induced phagocytic cell (would be lower). Since the count was of such cells were higher in the c-section birth even with the presence of ampicillin, we can conclude that the increased number of phagocytic cells are of significance and are due to stress. They also talk about how just the physical contractions are beneficial to the baby as they help the fetus squeeze out any fluid from the lungs, helping them breath easier after birth and reducing the probability of infant contracting pneumonia or bronchitis.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1905315/
This article was very interesting because it compared the immune system from babies born from a vaginal birth to a c-section. It highlighted a study done on their gut microbial communities. This is important because of all the helpful microbes that reside in our guts. I learned about the gut microbe in my Nutritional Neuroscience class and one thing for sure– it is very influential with our health including our weight, immunity and even certain diseases. This study stated lipopolysaccharide (LPS) biosynthesis was the main difference between the two study groups; I wonder if this process kills bacteria more effectively?
https://www.ncbi.nlm.nih.gov/pubmed/30972048
Upon reading this post, I found it very interesting that the mother’s microbiome can aid or negatively impact the microbiome of a newborn baby. Mothers that are able to give birth vaginally are able to pass microbes that aid in the newborn’s immune response. While babies that are delivered through cesarean are impacted negatively, ultimately affecting their immune system. Unfortunately, not all moms have the option to deliver their babies naturally. I wondered if there was any way the microbiome and the immune system of the new born could be improved. I was able to find an article that discusses microbial therapeutics to aid in health for infants. The article states that breast-feeding and natural delivery have become the “gold standard” because of the direct or indirect contact they experience with the mom. However, not all infants can experience this luxury, the article goes on to say that prebiotics are a good source in aiding in homeostasis and a good amount can be found in the mother’s breastmilk. If there are infants that can’t experience this, a change to the gut microbiome has been linked to many disorders among children such as childhood obesity, autism, and necrotizing enterocolitis. To change this increasing phenomenon in kids studies have been conducted to find ways to treat infants that are not able to get prebiotics that they would normally get from mom, to decrease the possibility of disturbances in the gut microbiome. In the study they aim to show the beneficial aspects of pre and probiotics on infant health. I think conducting studies like this, is very important because there has been an increase in cesarean birth which ultimately effects an infant’s health as they get older. Some women do not have the option of natural birth which puts their baby at risk, so finding a method to increase an infant’s microbiome to aid their immune system is a very interesting concept.
https://www.ncbi.nlm.nih.gov/pubmed/29124056
This article was very interesting because it compared the immune system from babies born from a vaginal birth to a c-section. Looking into how the mode of delivery influences the immune system, differentiation into T-lymphocytes was reduced following a c-section birth. This essentially means that once t cells mature, they will live longer in the body. However, this lack of maturation has the potential to lower the child’s future immune response to foreign material. C-sections were associated with 32% higher risk of having an infant with a lower number of newly formed T-lymphocytes. T-lymphocytes play an important role in the adaptive immune system by working to recognize foreign materials and either killing or helping other cells to kill. This article doesn’t state how c-sections reduce T-lymphocytes but the correlation is clear.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5599043/
This idea that the microbiome infants are introduced to, depending on method of birth, primes their immune systems for development in different ways is interesting to me. Personally, I don’t agree, I believe that the most crucial time of the immune system developing is reliant on their exposure as they grow during the first years of life. This study I found suggests that the amount of low-level exposure of infants to microbes as they develop actually helps them in the future with inflammation responses and immune protection. I chose this article because it directly exemplifies the connection between exposure and immune development. The more exposure the infant has as it develops, the more protected the infant’s immune system will be. The study aimed to determine immune-mediated classes that evolved in early life and further analysis revealed changes in white blood cell counts and inflammatory markers between those with higher exposure to microbes versus those with limited exposure. They found that the immune mediated classes strengthen during the first years of life where the atopic, the mixed, and the ACE classes all typically display positive relationships with chronic inflammation, whereas the resilient class displayed a negative relationship suggesting a protective relationship. So, the idea that the microbiome primes the infants for immune development does not convince me, because the crucial time is during the first years of life where the body is allowed exposure to all sorts of microbes in order to develop a strong immune system.
https://www.ncbi.nlm.nih.gov/pubmed/30961604
This article highlights one of the benefits an infant receives when birth happens vaginally. The one question I had while reading this article was what other ways in which infants can establish their normal flora that is related to how they were born. It is common knowledge that breastfeeding helps establish the normal flora of the gut of infants. Crohn’s disease is a chronic inflammatory disease that is generated from an abnormal immune response against the normal bacteria in the intestine. It was found that in the study, where mice are used as model organisms to better understand the disease, a deficiency in a phagocyte triggered the inflammation. A phagocytic NADPH oxidase trigger early-onset T-helper 1 inflammation in the intestine. This trigger leads to the accumulation of a gut microbe called Mucispirillum which kills neutrophils found in the lumen. It is found that when a mother breastfeeds her offspring, maternal immunoglobulins against the Mucispirillum are effective in preventing the accumulation of the bacterium in her offspring.
https://www.ncbi.nlm.nih.gov/pubmed/31004013
I find this to be logical as the vaginal delivery process is an inflammatory one. The inflammatory process involves many molecules. Without the vaginal delivery the neonate would not have first exposure to these cytokines. I picked the article Influence of mode of delivery on cytokine expression in cord blood because it also backed the claim of there being differences to the neonate via difference in mode of delivery. Both claim that the vaginal delivery is a beneficial process in exposing the neonate to these beneficial molecules. I did find it interesting that they did have different results for the presence of TNF-a. The Birth Mode, Microbiome, and Immune Response states that there showed a higher presence in the fecal sample of the neonates born vaginally but the article I picked states they found that there was a greater presence in the cord blood of the neonates born via caesarean. Both are sure in the fact that there is a difference in exposure in the difference of mode of delivery. I think more research into this would be beneficial as more woman are having caesarean delivery. If there is a link between immune disorders and children born via caesarean. TNF-a plays an important role in the regulation of immune cells. It is a cytokine that is involved in inducing inflammation.
https://www.ncbi.nlm.nih.gov/pubmed/30926352