Taking the type 2 diabetes drug metformin during pregnancy is not linked to a higher risk for overweight or obesity in young children, according to a new study published in the journal The Lancet Diabetes & Endocrinology.
Taking metformin during pregnancy has long been a controversial topic, but has gotten less so in recent years as studies have shown that the drug is safe when it comes to a number of potential pregnancy-related outcomes. This has been the case both for type 2 diabetes — in which case a pregnant woman may have previously taken metformin — and gestational diabetes, which has traditionally been treated with insulin if any glucose-lowering drug is needed. One study showed that for women with gestational diabetes, metformin was more effective than insulin for blood glucose control after some meals, and didn’t carry the risk for hypoglycemia (low blood glucose) that insulin did. Taking metformin also resulted in lower rates of induced labor and delivery by cesarean section (C-section).
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For the latest study, researchers compared rates of adiposity (overweight or obesity) in 283 young children of women who took either metformin or a placebo (inactive pill) during pregnancy. The children were followed until they were 2 years old. In the main study period of the trial during pregnancy, women with insulin-treated type 2 diabetes were given either 1,000 milligrams of metformin twice daily or a placebo — with all participants taking insulin as needed for blood glucose control, as noted in an article on the study at Healio.
Metformin in pregnancy not found to significantly impact children’s body weight
The researchers found that overall, there was no significant difference in body-mass index (BMI, a measure of body weight that takes height into account) between children of mothers who took metformin versus placebo during pregnancy after two years. While there was also no overall significant difference between the two groups in BMI trajectory up to that point — measurements were also taken when the children were 3, 6, 12, and 18 months old — among male children, BMI in the metformin group was higher between 6 and 24 months of age. Compared with a reference population of children outside the study, children in the study — whose mothers all had insulin-treated type 2 diabetes — were significantly heavier for their age at each step.
The researchers concluded that while young children of women with insulin-treated type 2 diabetes during pregnancy may be heavier than their counterparts from women without diabetes, taking metformin during pregnancy did not have a significant effect on the children’s body weight up to 2 years of age. These results should be seen as “reassuring with regard to the use of metformin during pregnancy in women with type 2 diabetes and the long-term health of their children,” the researchers wrote.
Want to learn more about metformin? Read “What to Know About Metformin,” “Diabetes Medicine: Metformin,” and “Metformin: The Unauthorized Biography.”
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