Road to fertility: comparison of letrozole and clomiphene citrate-estradiol valerate for ovulation induction in female with unexplained infertility to see ovulation and conception rate
Keywords:Infertility, Letrozole, Ovulation
Background: Clomiphene citrate was considered as first line of treatment for ovulation and induction in patients with unexplained infertility, but there are differences in results which can be explained by anti-estrogenic effect of CC resulting in estrogen receptor depletion. Letrozole is potent non-steroidal aromatase inhibitor which increases gonadotrophin secretion with ovarian follicle stimulation. Research question was that which drug is more efficacious for ovulation and induction in patients with unexplained infertility.
Methods: This comparative study was conducted at OBGYN OPD of RMCH and RC, Kanpur. Patients were 50 females with unexplained infertility randomly divided into 2 groups. Group A received letrozole 2.5 mg from D3-D7 of menstruation. Group B received CC 50 mg from D3-D7 plus 2 mg estradiol valerate BD on D8-D14 of menstruation. Female aged 18-35 years with complete fertility workup i.e. D3 FSH, LH, prolactin, serum TSH, HSG, USG-pelvis, mid luteal phase progesterone, semen analysis within normal limits are included in study. Patients with male infertility, hyperprolactinemia, thyroid disorders and BMI>30 kg/m2 were excluded.
Results: There was statistically significant difference in endometrial thickness (ET) between two groups, (p value <0.03) as mean ET was 9.3±1.7 in group A (L) and 8.3±1.5 in group B (CC+E). The number of follicles after stimulation were better with CC+E 2.9±1.1 and L 2.1±1.2 showing statistically significant difference with p value <0.01 but clinical pregnancy rate was higher with letrozole as compared to CC-E without statistically significant difference.
Conclusions: Letrozole has better effect on endometrial thickness with statistically significant difference. CC+E had advantage towards multifollicular development with statistically significant difference, but there was no significant difference in case of clinical pregnancy rate, abortion, ectopic, multiple gestation.
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