Comparison of Clinical and Sociodemographic Characteristics and Placental Microbiome in Women With Undernutrition Versus Normal Nutritional Status at Bungoma County Referral Hospital

Abstract

Background: Undernutrition remains a major burden in low-income countries and is considered a significant risk factor for morbidity and mortality among pregnant women and younger children. It impacts the immune system, especially through thymus gland atrophy with subsequent reduction in immature T-cells. During pregnancy, the placenta plays a critical role of transfer of nutrients from maternal blood to the fetus, hormone synthesis, and immune protection, among others. The effect of undernutrition on placental biology is little studied. Several bacteria in the phyla Tenericutes and Proteobacteria have been identified in the placenta,endometrium and the membranes and their impact is not clearly understood. The study aimed at comparing the placental microbiome in pregnant women of normal nutritional status versus pregnancy affected with undernutrition. Objective: To compare the clinical and sociodemographic characteristics and the microbiome from placentas of women with undernutrition versus those with normal nutritional status in pregnancy. Methodology: In this comparative cross-sectional study we studied 23 bio banked placentas from pregnant women with undernutrition and 25 from pregnant women with normal nutritional status. DNA extraction from 25 mg of thawed and minced placenta per sample was done at the Kenya AIDS Vaccine Initiative (KAVI) laboratory strictly following Burton’s protocol. The DNA samples were coded and transported to Macrogen Laboratory in Amsterdam, Netherlands for the next generation sequencing of the 16s RNA gene .The data on the clinical, sociodemographic and reproductive characteristics was derived from the clinical data forms. This data was entered into password protected excel sheets and analyzed using SPSS version 26. The Chi square test of association and/or Fisher’s test for the categorical variables while independent sample T-test/Mann Whitney test was used for continuous variables. A P-value of <0.05 was considered statistically significant. Results The level of education, placental and neonatal weights were significantly lower in pregnant women with undernutrition, while parity, age, and marital status were not significantly different between the 2 groups. The odds of being anemic, given that one is undernourished in pregnancy was high with an ODDs ratio of 17(3.84-76.43)and a p-value of <0.001. No microbiome was demonstrated in placentas from both groups. Conclusion Next Generation sequencing of the 16s RNA gene from placentas with undernutrition and those with normal nutrition fails to demonstrate presence of a microbiome. Undernutrition however is associated with low levels of education and anemia and thus there is need for nutritional counselling in pregnancy to help avert anemia which is a major indirect cause of maternal mortality.