Maurer-Major E, Keller P J
Departement Frauenheilkunde, Universitätsspital Zürich.
Praxis (Bern 1994). 1997 Oct 1;86(40):1543-8.
In the late sixties and seventies, publications of the Royal College of General Practitioners in England reported that in women using oral contraceptiva the incidence of venous thromboembolism is increased by two to four fold. Moreover, it was demonstrated, that these alterations in coagulation were induced by ethinylestradiol in a dose dependent manner. Following these findings, its dosage was lowered from more than 100 micrograms to 20-30 micrograms per day. More recently, the role of gestagens in inducing thrombosis has also been debated. Different authors observed an increased risk for venous thromboembolism in women using third generation pills containing gestoden or desogestrel compared with users of second generation levonorgestrel contraceptiva. These reports have generated a lot of concern and fear in the patients as well as doctors and have led to a drastic fall in the use of oral contraceptives. Due to the unavailability of safe contraceptive alternatives, the number of women experiencing unwanted pregnancy and its complications increased significantly. Indeed, direct proof for the role of gestagens in inducing thromboembolism is still lacking as the protocol designs of these studies do not allow us to infer whether the effects are due to the gestagens or to confounding variables. Hence, the discussions were beneficial for clinicians to remember the importance of checking the patient for individual and family risks for thrombosis before handling out a pill prescription.
在六十年代末和七十年代，英国皇家全科医师学院的出版物报道，使用口服避孕药的女性静脉血栓栓塞的发生率增加了两到四倍。此外，研究表明，这些凝血变化是由炔雌醇以剂量依赖的方式诱导的。基于这些发现，其剂量从每天超过100微克降至20 - 30微克。最近，孕激素在诱发血栓形成中的作用也受到了争论。不同的作者观察到，与使用第二代左炔诺孕酮避孕药的女性相比，使用含有孕二烯酮或去氧孕烯的第三代避孕药的女性发生静脉血栓栓塞的风险增加。这些报道在患者以及医生中引起了诸多关注和担忧，并导致口服避孕药的使用量急剧下降。由于缺乏安全的避孕替代方法，意外怀孕及其并发症的女性数量显著增加。事实上，由于这些研究的方案设计不允许我们推断这些影响是由于孕激素还是混杂变量，所以仍缺乏孕激素在诱发血栓栓塞中作用的直接证据。因此，这些讨论有助于临床医生记住在开避孕药处方之前检查患者个体和家族血栓形成风险的重要性。
