Results from a recent study reveal oral contraceptives are not all alike.

Researchers from the Kaiser Permanente Medical Care Program of Northern California recently released evidence linking oral contraceptives containing a highly androgenic progestin to a 43% increased risk of gestational diabetes, when used for five years leading up to pregnancy. Interestingly, oral contraceptives with a low androgenic progestin were associated with a 16% decreased risk of gestational diabetes.

Gestational diabetes develops in about 4% of pregnant women who have never had diabetes, but exhibit high blood sugar levels during pregnancy. Untreated, it can be dangerous for both mother and baby.

The study selected 356 women with gestational diabetes and 368 women without the condition from a multiethnic cohort of 14,235 women who delivered a baby between January 1996 and June 1998. The women were members of Kaiser Permanente for a minimum of five years before pregnancy and screened for the condition between 24-28 weeks of pregnancy. Medical records and pharmacy data were utilized to determine contraceptive use.

Researchers state their results support other related studies that confirm more androgenic oral contraceptives can impact glucose tolerance.