Oral contraception with low-dose progestagen
Heinzl, S.
Medizinische Monatsschrift für Pharmazeuten 12(4): 123-124
1989
ISSN/ISBN: 0342-9601 PMID: 2657358 Document Number: 327164
Gestoden is a gestagen from the 19-nortestosterone series. It has the strongest gestagen effect of any of the known gestagens. This permits a very low dosage in oral contraceptives in which 75 mcg of Gestoden are combined with 30 mcg of ethinylestradiol. Gestoden differs from levonorgestrel only in the presence of a double bond in rind D of the steroid chain. This small difference, however, is associated with an improved affinity to the progesterone receptors by a factor of 3. Gestoden does not exhibit either an estrogen nor an antiestrogen effect which suppresses the undesired effects of estrogen on the endometrium and on the metabolism. In clinical tests the combination of 75 mcg of gestoden and 30 mcg ethinylestradiol were used in phase II and III clinical tests in 17 countries with nearly 8,000 women in 60,000 cycles. In an ongoing phase IV study data from 200,000 cycles in almost 38,000 women has been gathered. In all studies pregnancy was very rare, at about the same level as other low dose combination contraceptives. 5% of the cycles exhibited bleeding irregularities. In the 1st few cycles, nausea, breast tension, acne and edema occasionally occurred but decreased with continued usage. No clinically meaningful changes in lipid or carbohydrate metabolism were observed. Blood studies on 60 healthy women taking the gestagen mixture or 150 mcg desogestrel showed low values of antithrombin III in the 36th week of treatment. Thrombocyte aggregation increased markedly with both preparations but less with gestoden than with desogestrel.