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Updated: Jun 9, 2026

Contractility Measurements of Human Uterine Smooth Muscle to Aid Drug Development
Published on: January 26, 2018
[Hormonal (levonorgestrel) emergency contraception--effectiveness and mechanism of action]
Lech M Medard1, Lucyna Ostrowska
1Ośrodek Badań na Płodnościa i Niepłodnościa w Warszawie. antykoncepcja@isf.pl
Abstract:
Periodic abstinence and coitus interruptus are the most popular methods of contraception in Poland. Recent studies have provided us with evidence that the so-called "menstrual calendar" may be much less effective than it was believed. In these circumstances, promotion and use of safe and truly effective contraceptives is very important for Polish women. Emergency contraception (EC) is a method which could be used even in cases when other contraception methods have failed. Mechanism of action of levonorgestrel used for EC and possible disturbances in the process of implantation of the blastocyst in the endometrium, remain the source of heated discussion among medical professionals. The latest publications provide us with evidence that the use of levonorgestrel in EC neither alters endometrial receptivity nor impedes implantation. Hormonal EC effectiveness is another hot topic of gynecological endocrinology and statistics. There is, however, no better, safer, and more ethically accepted method of preventing unwanted pregnancy for patients in need of postcoital contraception.
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