Does taking metformin during pregnancy have any long-term effects for children?

Rebecca Reynolds, Jane Norman

Metformin is a drug used to treat gestational diabetes. Our scientists want to understand whether the drug has any long-term effects on children. This will ensure that metformin can be used as a safe treatment to reduce the risks of diabetes for mother and baby.

Start: April 2017

End: April 2019

Why do we need this research?

Scientists supported by Tommy’s have been trying to understand how obesity during pregnancy affects children before and after birth. One common complication of obesity during pregnancy is gestational diabetes, which is normally treated with a drug called metformin. Researchers are now investigating whether metformin could reduce other risks linked to obesity during pregnancy, such as high birthweight.

Although metformin is safe to use during pregnancy, there is some evidence that it might increase the risk of obesity in children. We need to better understand the long-term effects of this commonly used drug for children.

What’s happening in this project?

A previous trial called EMPOWaR tested whether a drug called metformin could help obese women without diabetes to reduce their baby’s birthweight. The children born to the women who took part in the original EMPOWaR study are now about five years old. Researchers funded by Tommy’s have invited these women to take part in a follow-up study to understand what effects (if any) metformin has had on their child.

Our scientists have asked the women to fill out questionnaires about their child’s development, diet and exercise. The team also measured the children’s body composition (the amount of fat in their body), as well as their blood pressure and stiffness of their blood vessels. This is to understand if metformin might cause any heart or circulation problems.

The research team are now analysing all the data to confirm the effectives of metformin for these children.

What difference will this project make?

Metformin is frequently used during pregnancy to treat gestational diabetes. Previous work with the EMPOWaR study participants showed that taking metformin during pregnancy has no harmful effects on the placenta. This project will show whether or not there are any long-term effects for the children. The results will help doctors and parents understand the risks (if any) of metformin, allowing them to make informed choices about the treatment.

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