Maternal obesity impairs the structure of the placenta (a vital organ that nourishes the baby during pregnancy) more than gestational diabetes mellitus (GDM; a condition is diagnosed by poor blood sugar control during pregnancy). The new preview, published in The Journal of Physiology, improves understanding of the mechanisms underlying poor pregnancy outcomes and the resulting increased risk of poor neonatal and offspring health. Identifying specific changes in the placenta could lead to the potential development of future treatments or screening tests targeting the placenta that could improve maternal and offspring health outcomes, especially in low- and middle-income countries.
Rates of obesity and DG, the development of poor glucose management during pregnancy, are increasing worldwide. Both are linked to multiple maternal and fetal complications, such as an increased risk of fetal death, stillbirth, infant mortality, and higher birth weight. It is not known how these complications arise.
Researchers found that maternal obesity more than DG reduced placenta formation, its density and area of blood vessels, and its ability to exchange nutrients between mother and developing child. Obesity and DG both impact placental hormone production and markers of inflammation, suggesting that the placenta is indeed functioning abnormally.
The study involved 71 black or mixed-ancestry women. 52 were obese and 38 had developed GD. Researchers conducted the study using clinical profiling, in-depth structural examination and molecular analysis of the placenta, as well as biochemical measurements of maternal and infant cord blood to examine the effect of obesity and GDM in this group of pregnant women.
Lead author Professor Amanda Sferruzzi-Perri from the University of Cambridge said:
“For the first time, we examined the effects of obesity and GDM on the placenta in black and mixed-ancestry women, who are an understudied group, and the effect these conditions might have on them. and their children. This was important in discovering that obesity has more influence than GDM on the outcome of pregnancy, for both mother and child.”
The limitation of the study is that with a small sample of 71 women, it was not possible to determine the impact of the sex of the fetus on these placental changes. The group of non-obese women also included women who would be classified as overweight. Researchers would like to conduct further research on obese, overweight, and thin women with and without GD, and explore the impact of fetal sex. Next, they would like to study how obesity, gestational diabetes, and treatments, such as the blood sugar-lowering drug metformin, interact to determine pregnancy outcomes and the long-term health of the child.
Co-lead author Professor Mushi Matjila from the University of Cape Town said:
“South Africa is burdened with a quadruple burden of communicable and non-communicable diseases, as well as high maternal and child morbidity and mortality, and deaths related to violence and injury. one of the highest rates of female obesity in the world, which undoubtedly fuels the burden of non-communicable diseases and contributes to maternal, neonatal and child morbidity As obesity and GDM often coexist, the study highlights the importance of obesity relative to DG in modulating placental structure and function, and begins to piece together how these placental changes may account for observed complications (e.g., intrauterine death and stillbirths) and increased future risk of non-communicable diseases for mother and baby.”