This project represents the first systematic investigation of the impact of the microbiome on nutritional status during pregnancy in young women and directly aligns with global health initiatives focused on this vulnerable cohort. The goal of the study is to define the relationships between host nutritional status and microbiome dynamics during pregnancy and how they contribute to birth outcomes. The gut microbiome has a profound influence on host nutritional status. Dysbiosis (loss of diversity/beneficial microbes and gain of pathobionts) has emerged as a major factor in the development of undernutrition. Despite the importance of nutrition during pregnancy, few studies have examined the role of the microbiome on maternal health and birth outcomes. Further, little is known concerning the influence of enteric eukaryotic microbes, such as parasites, on the bacterial microbiome and host nutrition.

At the core of this study are two complementary cohorts of young women that provide an exceptional opportunity to obtain longitudinal samples to monitor the dynamic relationships between microbiome community structure and function with gut health and host nutritional status. This registration is for the Matiari, Pakistan cohort of the study, where there is known to be a high prevalence of undernutrition among young women. This cohort is expected to yield insights into the influence of eukaryotic microbes that are often viewed as asymptomatic. The target demographic of the study is young, married mothers, ≤24 years in Matiari District within the province of Sindh, Pakistan. Matiari District is representative of rural settings in Pakistan The investigators have identified this younger demographic due to the lack of knowledge on the microbiome of young women, and their vulnerability to undernutrition. A second complementary cohort will be based Toronto, Canada. This project will yield insights into the relationships between prokaryotic and eukaryotic microbes in the gut and their associations with maternal health and birth outcomes.

The central hypothesis of the study is that alterations of the microbiota in the maternal gut (dysbiosis) exacerbated by nutritional status or pathogen exposure during pregnancy, impacts weight gain because of impaired nutrient absorption, leading to corresponding negative birth outcomes.

The study will be a prospective, longitudinal, observational study to investigate the impact and relationship between prokaryotic and eukaryotic microbes in the gut and their association with maternal health and birth outcomes among married young women ≤24 years residing in Matiari District. . The study will aim to recruit 400 women into two groups based on BMI at time of recruitment (normal BMI will be defined as between 20 and 24.9 kg/m2 and low BMI will be defined as less than 20 kg/m2). With a goal of having 200 participants within the normal BMI group and 200 participants within the low BMI group. Although this is the recruitment aim, in the event that the investigators are unable to recruit 200 women with a low BMI, more women will be recruited that fall within the normal BMI range. The study will follow women and their infants over the course of their pregnancy and for a year postpartum, collecting stool, rectal and blood samples, nutritional information, heath assessments, anthropometric measurements and empowerment metrics at different time points.