Effect of oral estrogen supplement on gonadotropin-induced intrauterine insemination: A retrospective cohort study

Abstract

Aim: The effect of estrogen on gonadotropin-induced intrauterine insemination (GI-IUI) is not well studied. Furthermore, risk factors for clinical pregnancy rates are not clearly defined. This study aimed to evaluate the effects of oral estrogen supplementation and clinical pregnancy rates on GI-IUI.
 Material and Method: Patients treated with primary and secondary infertility were retrospectively analyzed between September 2016 and September 2019. IUI session was performed after ovarian stimulation with human chorionic gonadotropin. Patients were supplemented with a vaginal gel containing progesterone and oral estrogen (Group A) or only the vaginal gel (Group B). The differences between the groups in pregnancy rate and endometrial thickness and the risk factors associated with clinical pregnancy were determined as primary and secondary outcomes, respectively.
 Results: A total of 112 couples were evaluated, where the mean age for females was 31.3±6.1 years. Group A and Group B had 33 (29.5%) and 79 patients (70.5%), respectively. Duration of infertility, number of follicles, and endometrial thickness were significantly different between the two groups. The rate of pregnancy was significantly higher in Group A (51.5%) than in Group B (19%) (p=0.001). There were significant differences between positive and negative pregnancy cases in terms of age, type and duration of infertility, estradiol level, motile sperm number and morphology, number of follicles, and endometrial thickness. The follicle count and estradiol levels were significant risk factors for clinical pregnancy.
 Conclusion: Estrogen has a positive effect on pregnancy rates in GI-IUI. The follicle number and estradiol level can be used as a risk factor for IUI.