Effect of sildenafil citrate on endometrial preparation and on the outcome of the frozen-thawed embryo transfer cycles in infertile women: a clinical trial

Purpose: The aim of this study is to estimate the effect of sildenafil on endometrial thickness, endometrial pattern, and investigate estrogen level on the day of progesterone administration, the implantation rate and chemical pregnancy rate in frozen embryo transfer cycles . Methods: 80 women younger than 40 years who had high quality frozen embryos with history of poor endometrial response were included in the study and based on random allocation are divided in two groups. For group I (n=40) start 2mg estradiol valerat (tablet) from first to 4th day of the menstrual cycle, and continue by 4mg from 5th to 8th day, and 6mg from 9th to 20th day of the menstrual cycle. In the second group (n=40) in addition to the above treatment protocol, from first day of cycle until the day of starting progesterone will be given 50mg sildenafil citrate tablets daily and it was discontinued from 48 to 72 hr prior to the embryo transfer. In 13th day of the menstrual cycle endometrial thickness measured with transvaginal ultrasonography (arranged in a series every other day). Evaluations were performed by a single investigato. If the endometrial thickness is more than 8mm, 100 mg progesterone injected intramuscular and blood estrogen, progesterone level are measured then after three days embryo was transferred. Outcomes: Estradiol valerat and progesterone continued until two weeks after embryo transferred, then BHCG tested. If BHCG is positive, estradiol valerat and progesterone continues until 11 weeks of pregnancy . Then four weeks after the embryo transfer, the number of gestational sac are determined by vaginal ultrasound.

Yazd Shahid Sadoughi University of Medical Sciences, Vice chancellor for research