Endometrial preparation for in vitro oocyte maturation: early use of estrogen increases endometrial tissue and requires lower daily dosage: a cross over trial in 'mock' cycles.

PURPOSE: Determine if estrogen used since the beginning of the menstrual flow could improve endometrial tissue compared to standard endometrial preparation for in vitro maturation cycles.

METHODS

Twenty polycystic ovary syndrome women were submitted to two estrogen therapy schedules: standard schedule; estrogen began on the day of planned egg retrieval (dosage was based on endometrial thickness); and long schedule; estrogen began on the first day of menstruation. No oocyte retrieval or embryo transfer was performed. Three-dimensional ultrasound was performed on the day of planned egg retrieval and one week later for endometrial evaluation.

RESULTS

A higher endometrial thickness and volume was found in long schedule on both evaluations. The number of patients that have used 10 mg/day of estradiol was significant higher in the standard schedule (65%x0%). No other significant difference was found.

CONCLUSIONS

The early use of estrogen improves endometrial tissue and requires lower daily dosage.