Comparison of Clomiphene Alone Versus Clomiphene Plus Sildenafil for Ovulation in Women With Polycystic Ovary Syndrome

The goal of this randomized clinical trial is to compare the effectiveness of clomiphene citrate alone with clomiphene citrate combined with sildenafil citrate for inducing ovulation and achieving pregnancy in women with polycystic ovary syndrome (PCOS) who have difficulty becoming pregnant. The main question the study aims to answer is: Does adding sildenafil citrate to clomiphene citrate increase the chance of ovulation and pregnancy compared with clomiphene citrate alone in women with PCOS? The study will include 98 women aged 18-45 years with PCOS and a history of difficulty achieving pregnancy for more than 2 years. Participants will be randomly assigned to one of two groups. * Participants in Group A will receive clomiphene citrate 100 mg once daily from days 3-7 of the menstrual cycle, plus sildenafil citrate 25 mg twice daily from days 8-12. * Participants in Group B will receive clomiphene citrate 100 mg once daily from days 3-7, plus a placebo twice daily from days 8-12. Treatment will be given for 12 weeks. Participants will be assessed for ovulation, pregnancy, and endometrial thickness. Ovulation will be assessed using transvaginal ultrasound and/or a blood progesterone test. Pregnancy will be assessed using a urine pregnancy test and/or ultrasound. The primary hypothesis is that women receiving clomiphene citrate plus sildenafil citrate will have a higher rate of pregnancy than women receiving clomiphene citrate alone. The study will also determine whether adding sildenafil improves ovulation and endometrial thickness.

Inclusion Criteria: * Women with PCOS, * Sub-fertility attributed to PCOS, \> 2 years Exclusion Criteria: * Comorbidities; diabetes, hypertension * Chronic medical illness (liver, heart, kidney disease) * Undergone ovarian drilling * Recent administration of hormonal therapy * Abnormal prolactin levels (\>500 mIU/L), or thyroid function tests (TSH \>5.2 mIU/L, T3 \