No association in maternal serum levels of TMAO and its precursors in pre-eclampsia and in non-complicated pregnancies.

Only a few studies have explored the role of microbiota-dependent metabolite trimethylamine N-oxide (TMAO) in non-complicated pregnancy and in pre-eclampsia (PE). We enrolled 139 PE and 29 healthy pregnant women in a nested case control study. We hypothesized that elevated levels of circulating TMAO and its precursors choline and glycine betaine in the late second or in third trimester might contribute to the PE and are associated with the onset of the disease and clinical features such as elevated blood pressure. The association with a few available lifestyle factors (use of fish and physical activity) was also evaluated. In contrast with the previous findings, there was no difference in TMAO concentration between PE and healthy women. In addition, TMAO concentration was not associated with any of the PE related clinical features, angiogenic or inflammatory markers. In future, it is crucial to obtain longitudinal data on TMAO in both non-complicated and in PE pregnancies before we could have more detailed understanding of TMAO.