Horm Metab Res 2010; 42(5): 358-363
DOI: 10.1055/s-0030-1248263
Humans, Clinical

© Georg Thieme Verlag KG Stuttgart · New York

Effects of Combined Oral Contraceptive Ethinylestradiol (30 μg) and Dienogest (2 mg) on Carbohydrate Metabolism During 1 Year of Conventional or Extended-Cycle Use

I. Wiegratz1 , S. Stahlberg1 , T. Manthey1 , N. Sänger1 , K. Mittmann2 , E. Palombo-Kinne2 , U. Mellinger2 , E. Lange2 , H. Kuhl1
  • 1Center of Obstetrics and Gynecology, University Hospital of Frankfurt, Frankfurt/M, Germany
  • 2Jenapharm GmbH & Co KG, Jena, Germany
Further Information

Publication History

received 02.07.2009

accepted 20.01.2010

Publication Date:
08 March 2010 (online)

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Abstract

The effects of extended regimens of combined oral contraceptives (COCs) on carbohydrate metabolism are largely unknown. The present study compared the effects of a COC containing 30 μg ethinylestradiol and 2 mg dienogest (EE/DNG) in conventional and extended-cycle regimen over 1 year. Parameters of carbohydrate metabolism were measured in 59 women treated with EE/DNG either conventionally (13 cycles of 21+7 days) or in extended-cycle regimen (4 cycles of 84+7 days). Blood samples were taken in a control cycle, and at 3 and 12 months of treatment. The mean levels of HbA1c and fasting glucose levels remained stable in both conventional and extended-regimen of EE/DNG. The mean levels of fasting insulin and C-peptide underwent comparable increases in both regimens, suggesting a similar readjustment of glucose metabolism via slightly increased insulin secretion. For both regimens, the response to the oral glucose tolerance test (OGTT) showed a slightly impaired glucose tolerance and insulin resistance at 3 months. These changes improved or returned to baseline at 12 months. Accordingly, the mean index for insulin resistance (homeostasis model assessment of insulin resistance, HOMA-IR) increased and the mean insulin sensitivity index [ISI (composite)] decreased modestly in both groups. The present study demonstrates that there are no statistically significant differences between the effects of conventional and extended-cycle treatment on carbohydrate metabolism over 1 year of treatment. In general, the effects of both regimens were moderate and mostly transient.