Bruno Mozzanega
University of Padua, Italy

Title: Emergency contraceptives work prevalently through a post-fertilization, anti-implantation, mechanism
Time: 15:30 - 16:20


Bruno Mozzanega, md, is author/co-author of over 180 scientific papers, included presentations in Congresses and abstracts. He wrote a textbook (Da Vita a Vita-IIIrd Ed. SEU, Rome,2013). He participated in researches about menopause since 1980, in particular concerning the oncogen and cardio-vascular risk, osteoporosis and coagulation disorders, the circulating levels of Insulin Like Growth Factors and their Binding Proteins during different schedules of HRT, the endometrial features in breast cancer patients treated by tamoxifen. He participated in the pioneer studies (1980) on the assay of sex steroids hormonal receptors in hormone dependent benign and neoplastic diseases. He collaborated in Molecular Biology researches concerning the endometrium in PCOS. Currently, he is highly interested in the mechanism of action of emergency contraceptives and actively works in forming high-school teachers and students in Reproduction knowledge and Fertility Control. He is the President of the Italian Society of Responsible Procreation (SIPRe,

Research Interest


Statement of the Problem - Emergency Contraceptive Pills (ECPs) are described as drugs that work  by either inhibiting or delaying ovulation without affecting implantation. In our opinion, however, EMA documents and the experimental papers indicate that they prevalently inhibit embryo-implantation.

Literature concerning LNG-ECPs - The EMA-EPAR on ellaOne® (Table 1, p.9)  reports that LNG never prevents ovulation when is taken in the most fertile days. On the contrary, it prevents the formation of an adequate corpus luteum.

Literature concerning UPA-ECPs - The EMA-CHMP Assessment-Report on ellaOne® (EMA/73099/2015, Table 2, p.7), evidences that 91.7% of women taking ellaOne® weekly for eight consecutive weeks have normal ovulation, with a permeable cervical mucus.

Besides, literature shows that ellaOne® prevents ovulation only when is taken in the first fertile day. Thereafter its anti-ovulatory effect drops sharply and becomes insignificant (8%) 36 hours before ovulation, in the most fertile days; its decreasing trend cannot explain a consistently high effectiveness in preventing pregnancies (?80%) that does not decrease depending on which of the five days it is taken after unprotected intercourse.

Lastly, Lira-Albarràn administered ellaOne® to women in the most fertile pre-ovulatory days: they had normal ovulation, but their endometrium, evaluated through samples obtained in the implantation window, became inhospitable: the expression of 1183 genes was exactly the opposite of that observed in the receptive pro-gestational endometrium. This agrees with information by EMA-CHMP Assessment-Report for ellaOne® (EMEA-261787-2009,p.8): after UPA administration “the proteins necessary to begin and maintain pregnancy are not synthesized.”

In EMA/73099/2015(p.9), EMA removed the warning against repeated administration of ellaOne ellaOne® within the same menstrual cycle, basing on HRA2914-554 study, where women were exposed to UPA-amounts equal to or higher than theose, potentially hepatotoxic, taken through Esmya®.

Conclusion - Emergency Contraceptives work prevalently by preventing embryo-implantation. People shall receive correct information.