The study evaluates the effect of coenzyme q 10 on ovulation and subsequent pregnancy in women with polycystic ovarian syndrome. Half of the participants will receive coq10 and ovulation induction with clomiphene and other half would receive a placebo with clomiphene.

Inclusion Criteria:

• Diagnosis of polycystic ovarian syndrome PCOS based on the revised 2003 consensus on diagnostic criteria and long-term health risks related to PCOS (2003).
• All women were previously treated with 100 mg of CC daily for 5 days per cycle, for two to three cycles with persistent anovulation or ovulate with very thin endometrium <5 mm at the time of hCG administration

Exclusion Criteria:

• Non-consenting.
• known autoimmune disorders
• prior treatment of endometriosis or surgery to reproductive tract
• prior history of pelvic inflammatory disease
• those with tubal factors and uterine factors as assessed on history and confirmed by normal hysterosalpingogram.
• Thyroid disorder as assessed by history examination and TSH level
• Patients with raised FSH