Article Abstract:
Women who take oral contraceptives (OC) are at risk for blood clot formation (thrombosis). It is thought that the hormones in the oral contraceptive formulas affect components of the blood clotting cascade, which triggers the formation of blood clots. These blood clots can block blood vessels anywhere in the body. Newer low-dose oral contraceptive formulas have decreased the risk of thrombotic events. Fibrin, the basic protein component of blood clots, can be regulated by inhibiting the formation of the clot with inhibitors or removing the fibrin from the clot. The activation of fibrinopeptide A and factor VII, agents that activate the blood clotting process, and antithrombin III and protein C, inhibitors of the clotting process, were assessed in women receiving low-dose oral contraceptives. The women were given either a monophasic OC (15 women), a pill containing the same amount of estrogen and progesterone (30 micrograms of ethinyl estradiol and 75 micrograms of gestodene) throughout the cycle, or a triphasic OC (15 women), which delivers a different combination of hormones each week over a three-week cycle. There were no changes in the activity of platelets, cells that clump and secrete factors during clotting. There was an increase in the level of factor VII and fibrinopeptide A after three cycles (three months). Antithrombin III activity increased slightly during treatment with the triphasic pills. There was no change in protein C concentration. Six and nine months later, factor VII was still high, whereas fibrinopeptide A was significantly lower. It is concluded that factors that inhibit thrombosis offset the initial tendency to clot during oral contraceptive treatments, which helps to minimize the long-term effects of hormone administration. (Consumer Summary produced by Reliance Medical Information, Inc.)
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
There is an association between oral contraceptive (OC) use and cardiovascular disease. Woman who take OCs are at risk for the formation of blood clots (thrombosis), which can block blood vessels serving the heart, lungs, brain and legs. Newer low-dose OC formulas are thought to reduce the risk of thrombosis. One of two OC formulas, 30 micrograms of ethinyl estradiol plus 75 micrograms of gestodene or 150 micrograms of desogestrel, was given to 60 healthy women. Factors involved in the formation and inhibition of clots were measured before, at 12, 24, 36 and 48 weeks of treatment, and 6 and 12 weeks after treatment. Factors involved in the clot dissolving process (fibrinolysis) and platelet activity (the cells that clump and secrete clotting factors) were examined. Both low-dose formulas altered the blood clotting system similarly. Factors VII and X were higher in women who took the estradiol/desogestrel formula than in women receiving the estradiol/gestodene formula. This may have been caused by the estrogen-dominant effect of the estradiol/desogestrel formula. Therefore, there still seems to be a risk of thrombosis with the low-dose oral contraceptive formulas. (Consumer Summary produced by Reliance Medical Information, Inc.)
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
The oral contraceptive Mircette effectively suppresses ovulation longer than some other contraceptives while minimizing exposure to estrogen. Mircette includes 5 days of low-dose estrogen during the traditional 7-day hormone-free period. This effectively reduces the hormone-free period. Researchers used ultrasound scans to detect the formation of ovarian follicles in women taking Mircette who received a placebo during the 7 hormone-free days or low-dose estrogen for 5 of those days. The women who received a placebo had a higher rate of follicle formation, which is a precursor of ovulation, as well as bigger follicles.
User Contributions:
Comment about this article or add new information about this topic: