Impact of Pre-eclampsia and Emergency Cesarean Section without Labour on Bifidobacterium  Levels in Infant Gut Microbiota
Creators: Paraktoon, Maryam
Publisher: name: University of Alberta Library
Year: 2023

<p>Background: <br>
Pre-eclampsia affects 8-10% of all pregnancies, resulting in significant maternal-fetal morbidity, <br>
including fetal distress, abnormal fetal heart rate, and placental abruption. These conditions also <br>
increase the risk of emergency cesarean delivery for pre-eclamptic women<br>
before a trial of labour. <br>
Furthermore, pre-eclamptic women face a higher likelihood of experiencing premature rupture of <br>
membranes (PROM), which has negative consequences for both mothers and infants. Recent <br>
findings have indicated that there are distinct gut microbiota changes in groups with pre-eclampsia <br>
compared to healthy control groups, thus confirming the potential link between dysbiosis of the <br>
gut microbiota and the occurrence of pre-eclampsia. However, there is lack of knowledge <br>
regarding gut microbiota alterations in infants born to pre-eclamptic mothers. Since critical gut <br>
microbiota and immune system interactions can be affected by microbial dysbiosis resulting from <br>
maternal health conditions, cesarean birth, and other birth events, the current study aimed to <br>
investigate the association between pre-eclampsia and the levels of key microbiota, <br>
Bifidobacterium, in the infant gut at 3 months of age. Additionally, this study aimed to explore <br>
whether this association is independent of emergency cesarean delivery without labour and <br>
premature rupture of membranes (PROM), as well as to determine if these factors mediate the <br>
observed association.<br>
Methods:<br>
This was a prospective cohort study utilizing data on 1429 mother-infant pairs, longitudinally from <br>
the Canadian Healthy Infant Longitudinal Development (CHILD) population-based birth cohort. Data on delivery mode, pre-eclampsia, PROM, breastfeeding status, maternal pre-pregnancy BMI <br>
and other maternal and infant covariates were collected from hospital records or standard maternal <br>
questionnaires. Infant fecal samples, collected at 3-4 months of age, were profiled by qPCR for <br>
levels of total Bifidobacterium. Fisher&#39;s exact tests was employed to assess crude unadjusted <br>
associations between maternal and infant characteristics with pre-eclampsia, emergency cesarean <br>
section without labour, and Bifidobacterium levels. To enhance data normality, Bifidobacterium<br>
values underwent Box-Cox transformation before logistic regression analysis. Simple and multiple <br>
logistic regressions (using STATA version 17) were utilized to identify the impact of preeclampsia on Bifidobacterium levels in the infant gut microbiome, while considering adjustments <br>
for potential confounding variables as suggested by the Directed Acyclic Graph (DAG). <br>
Additionally, mediation analyses were conducted using the Hayes PROCESS v3.5 macro in SPSS <br>
(version 26, SPSS Inc., Chicago, IL, USA) to examine whether emergency cesarean delivery <br>
without labour and premature rupture of membranes (PROM) are in the pathway between preeclampsia and Bifidobacterium levels in infant. <br>
Results:<br>
In our study, we observed a significant inverse association between pre-eclampsia and <br>
Bifidobacterium levels in the gut microbiota of infants at 3 months of age in the crude logistic<br>
analysis (βc: -1.48, 95% CI: -2.9, -0.05, p &lt; 0.05). However, after adjusting for potential <br>
confounding variables, this association lost its significance (βa: 0.31, 95% CI: -1.28, 1.90, p &gt; <br>
0.05). Furthermore, our investigation into the mediation process using simple and sequential <br>
analyses did not fully support the hypothesis that emergency cesarean delivery without labour and <br>
premature rupture of membranes (PROM) act as mediators between pre-eclampsia and <br>
Bifidobacterium levels in the infant gut microbiota. However, when examining the role of birth. mode as a mediator, our mediation analyses revealed a significant inverse association between <br>
cesarean section (elective and emergency CS with and without labour) and Bifidobacterium levels <br>
in the infant gut microbiota at 3 months of age. Additionally, we found similar results in the second <br>
mediation model, indicating that rupture of membranes has an inverse impact on Bifidobacterium <br>
levels in the infant gut.<br>
Conclusion:<br>
To summarize, our findings indicate that infants born to mothers with pre-eclampsia had decreased <br>
levels of Bifidobacterium in their gut at 3 months of age. However, it is important to note that the <br>
statistical significance of this association was not maintained after adjusting for potential <br>
confounding variables due to the limited sample size. Our study also revealed that cesarean section<br>
including elective and emergency CS with and without labour, had an inverse influence on <br>
Bifidobacterium levels, aligning with previous research findings. Furthermore, we observed an <br>
inverse association between rupture of membranes and Bifidobacterium levels, which warrants <br>
further investigation.</p>