Background: The aim of this 5-year retrospective study is to define the efficacy of oestro-progestinic interception.
Methods: An oestro-progestinic mixture (0.05 mg ethinyl estradiol and 0.250 mg dlnorgestrel) was prescribed to 6003 women attending the gynaecological outpatients clinic of AIED (Associazione Italiana per l'Educazione Demografica) in Genoa, Italy, without evidence of any previous contra-indications. The prescription was of two pills at once and two pills 12 hours after. Before examination, the doctor asked for personal and medical history (age, date of onset of menses, unprotected intercourse date and anticonceptional failure); patients were also asked to report the data of the following menses to the clinic. The largest age range was between 20 and 24 years, probably because of their inadequate knowledge of contraceptives. The reasons for post-coital contraception were: sexual intercourse without contraceptive, failure of coitus interruptus and of the condom.
Results: Post-coital interception efficacy (monthly oestro-progestinic contraception was 99.5%) according to retrospective statistical analysis, was according to Pearl index 92.9% vs 50% without any contraceptive.
Conclusions: Finally, the efficacy of this method, together with its easy management and low frequency of severe contra-indications, allows us to indicate the "morning after pill" as one of the most useful outpatient strategies to avoid unwanted pregnancies.