Pre-diabetes could put your baby at risk
Pregnant women with blood sugar levels in the higher range of normal – but not high enough to be considered diabetes – are more likely than women with lower blood sugar levels to give birth to babies at risk for many of the same problems seen in babies born to women with diabetes during pregnancy, according to a new study.
These problems include a greater likelihood of caesarean delivery and an abnormally large body size at birth. Babies born to women with higher blood sugar levels are also at risk of shoulder dystocia, where their shoulders becomes lodged inside the mother’s body during the birth, effectively halting the birth process.
The study authors declined to make recommendations for acceptable blood sugar levels for pregnant women and weren’t able to identify a precise level where an elevation in blood sugar increased the risk for any of the outcomes observed in the study. Rather, the chances for the outcomes were observed to increase gradually, corresponding with increases in a mom-to-be’s blood sugar levels.
It’s well known that the high blood sugar levels characteristic of gestational diabetes present risks for expectant moms and their babies. The current study is the first to document that higher blood sugar levels that aren’t high enough to be considered diabetes also convey these increased risks. Furthermore, when the researchers mathematically adjusted for other potential causes of these risks – such as older maternal age, obesity, and high blood pressure – the increased risks due to higher blood sugar levels were still present.
“These important new findings highlight the risks of elevated blood sugar levels during pregnancy,” says Duane Alexander, MD, director of the National Institutes of Health Eunice Kennedy Shriver National Institute of Child Health and Human Development, which provided much of the funding for the study.
Diabetes results from difficulty transferring sugar (glucose) from the blood to the body’s tissues. It occurs in roughly 5% of all pregnancies in the US. Moms-to-be with diabetes during pregnancy are also at increased risk for pre-eclampsia, a potentially fatal disorder involving dangerously high blood pressure. And once they reach adulthood, babies born to moms with diabetes are at higher risk for obesity as well as diabetes, high blood pressure, and heart disease.
According to Dr Metzger, before the current study physicians weren’t sure at which point elevated maternal blood sugar posed a risk for the baby. Frequently, high maternal blood sugar levels accompany such conditions as obesity, high blood pressure and older maternal age – all known to increase the likelihood of a cesarean delivery. For this reason, it wasn’t known whether the increased risk of cesareans and other problems seen with mild elevations in blood sugar during pregnancy were caused by the elevated blood sugar levels, or by these accompanying conditions. In their study, however, the researchers made adjustments for these accompanying conditions and found that the higher blood sugar levels still conveyed increased risks.
In the study, those moms with high blood sugar levels had a greater risk of delivering by cesarean section. In addition, the higher their blood sugar levels were, the more likely their babies were to have high insulin levels and low blood sugar levels at birth – both of which indicate exposure to high glucose levels in the uterus. Moreover, the higher the mom’s blood sugar levels, the more likely she was to develop pre-eclampsia, and the more likely her baby was to be born prematurely, and to experience shoulder dystocia. So, for example, women with the lowest blood sugar levels gave birth to abnormally large babies roughly 5% – but women with the highest blood sugar level gave birth to large babies 26% of the time.