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What Causes Gestational Diabetes?

Gestational diabetes is the result of some hormonal changes that occur in all women during pregnancy. Increased levels of certain hormones made in the placenta (the organ that connects the baby by the umbilical cord to the uterus and transfers nutrients from the mother to the baby) interfere with the ability of insulin to manage sugar (glucose). This condition is called "insulin resistance." As the placenta grows larger during pregnancy, it produces more hormones and increases this insulin resistance.

Usually the mother's pancreas is able to produce more insulin (about three times the normal amount) to overcome the insulin resistance. If, however, the pancreas cannot produce enough insulin to overcome the effect of the increased hormones during pregnancy, sugar levels will rise, resulting in gestational diabetes.

WebMD Medical Reference

Reviewed by Trina Pagano, MD on October 04, 2012

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