Hysteroscopic procedures are best performed when the endometrium is thin, but it is not always possible to schedule the procedure at the appropriate time. The aim of this study was to describe the endometrial effects of medical pre-treatment with oral contraceptives (OC) and increase the ease and safety of the procedure. Patients underwent pretreatment with lowdose OC beginning on menstrual days 1-3. The surgery was scheduled on days 7-25 of the second cycle of OC administration. Estradiol (E2) and progesterone (P4) on the first and the second cycle of OC administration were statistically similar (p<0.01) . There was unpredictable bleeding in 27% of the patients on the first cycle of OC administration. The endometrium surrounding the lesions of interest was almost always thin and flat, such that the operating conditions were excellent. Pretreatment of the endometrium before surgery with OC has been shown to reduce the thickness and vascularity of the endometrium, decrease the amount of tissue removed, improve visualization, reduce operating time and fluid deficits, and increase the ease and safety of procedure. The basis for the effect is due to OC with minimal doses of E2 and P4, thus causing endometrial atrophy.
