COMBI study

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One in seven babies in Africa are born with low birthweight, either because they are born too small (small-for-gestational age; SGA) or born too soon (preterm). Babies born SGA or preterm have a higher risk of dying, and do not grow as well in early life, leading to a higher risk of malnutrition. We want to understand the biological pathways that lead to babies being born too small or too soon and identify new strategies to prevent this from occurring. 

We know that pregnant women who have preterm or SGA babies have more inflammation at different body sites. 

The COMBI study was a phase 3 randomised controlled trial testing prophylactic use of the antibiotic cotrimoxazole throughout pregnancy on birth outcomes. 1000 pregnant women were enrolled in Shurugwi district, Zimbabwe and randomized to receive cotrimoxazole or placebo from their first antenatal visit (median 21 weeks) until the end of pregnancy. As part of this study we collected stool samples, vaginal swabs and oral samples from women at 3 timepoints throughout pregnancy to ask the following questions:

• Does long term prophylactic antibiotic therapy alter gut, vaginal and oral microbiomes during pregnancy?
• To what extent do gut, vaginal and oral microbiomes during pregnancy predict adverse birth outcomes in women living in rural sub-Saharan Africa?
• Do gut, vaginal and oral microbiomes drive inflammatory pathways in preterm birth?

We are currently conducting large-scale metagenome sequencing analyses and in vitro assays to address some of these questions.