Vaginal progesterone for the prevention of preterm birth and the risk of gestational diabetes.

INTRODUCTION

We aimed to determine whether daily vaginal progesterone use for the prevention of preterm birth has an effect on the incidence of abnormal glucose challenge test or gestational diabetes.

STUDY DESIGN

A retrospective study in a large referral center. Women with cervical length ≤ 25 mm were given 200 mg vaginal micronized progesterone capsules daily at bed time until 36 weeks` gestation or delivery. Each progesterone-treated woman was matched randomly with three untreated controls. The main outcome measures were; mean plasma glucose level following the glucose challenge test and the rate of abnormal 1-hour glucose challenge test. Secondary outcome was the rate of gestational diabetes.

RESULTS

We identified 108 progesterone-treated women that were matched by age and BMI to 324 controls during the same time period. The mean plasma glucose level following the glucose challenge test was similar in both groups (115.3 ± 33.8 mg/dL versus 109.2 ± 26.6 mg/dL). Despite a higher rate of an abnormal glucose challenge test in the progesterone-treated group compared to the control group (21.1% vs. 13.9%), it did not reach statistical significance. Similarly, we could not detect any difference in the rate of gestational diabetes in either the study or the control group (2.8% versus 2.5%).

CONCLUSION

Daily vaginal progesterone was not associated with higher rates of abnormal glucose challenge test or gestational diabetes. We are in a view that no earlier screening or diagnostic testing for gestational diabetes is required except the standard recommended schedule unless additional risk factors are present.