Endometrial response to ethinyl estradiol and sildenafil as adjuvant therapy with clomiphene citrate in unexplained infertility patients

ABSTRACT

Adverse effects of clomiphene citrate [C C] on the endometrium are likely to be the primary cause of the suboptimal pregnancy rates in ovulation induction with clomiphene citrate. The aim of this study was to examine the effect of adjuvant ethinyl estradiol [E E] or sildenafil citrate with clomiphene citrate to oppose this effect and improve thickness, morphology of endometrium and uterine resistance [R I] and pulsatity indices [R I]. One hundred and twenty patients of unexplained infertility were divided into four groups, the first is the control group who received no medications, the second group received clomiphene citrate for induction of ovulation, the third group received clomiphene citrate with ethinyl estradiol, the fourth group received C C with sildenafil citrate. For each patient serial vaginal ultrasound folliculometry was done with evaluation of endometrium at time of dominant follicle detection and color doppler study of the uterine artery on either side. Endometrial thickness and morphology were significantly affected in group 2 [C C] compared to control group [9.6 +/- 1.4] and 10% compared to[10.7 +/- 1.6] and 43% respectively. This was not significant comparing group 3 [E E] and group 4 [sildenafil] with control group [10.8 +/- 1.2] and 47% and [10.6 +/- 1.3] and 57% respectively. Also, uterine P I was significantly increased in group 2 [2.87 +/- 0.05] compared to other groups, while R I of uterine artery was not significantly different between any of the groups. Endometrial thickness and pattern were adversely affected with the use of clomiphene citrate alone, an effect which was corrected by adding ethinyl estradiol or sildenafil as adjuvant therapy to clomiphene citrate more with sildenafil than ethinyl estradiol