Randomized Controlled Trial of Combined Letrozole and Clomid (CLC II) Versus Letrozole Alone for Women With Anovulation

Inclusion Criteria:

1. Willing to comply with all study procedures and be available for the duration of thestudy
2. Diagnosis of infertility: Inability of couple to achieve successful pregnancy after 12months of regular time unprotected intercourse in women less than 35 years of age; andafter 6 months of regular intercourse without use of contraception in women 35 yearsand older. Women that have anovulation or oligomenorrhea are also considered to meetdiagnosis of infertility, without meeting the time constraints described above.
3. Diagnosis of polycystic ovary syndrome based on Revised Rotterdam criteria.
4. Ability to have regular intercourse during the ovulation induction phase of the study.
5. Partner with a normal sperm concentration of 15 million/mL and with normal motility of >40% according to World Health Organization cutoff points or greater than 10 milliontotal motile sperm count OR has fathered a pregnancy in the past.

Exclusion Criteria:

1. Current pregnancy
2. Current use of hormonal contraception; use of any type of combined contraceptive ororal progestins within the past month; or use of hormonal implants or depo progestinswithin the past 3 months
3. Other known cause of infertility: endometriosis, tubal factor, uterine abnormalities
4. Uncorrected thyroid disease
5. Untreated hyperprolactinemia
6. Medical conditions in which avoiding pregnancy is recommended until under improvedcontrol: poorly controlled Type 1 or Type 2 diabetes, poorly controlled hypertension
7. Contraindications to clomiphene citrate: hypersensitivity to clomiphene citrate or anyof its components, history of liver disease or known liver disease, unknown cause ofabnormal uterine bleeding, or intracranial lesion
8. Contraindications to letrozole: hypersensitivity to letrozole or any of its components
9. Use of medications known to affect reproductive function or metabolism or that are anabsolute contraindication during pregnancy within the past month
10. If patients are suspected based on clinical findings for other etiologies that mimicPCOS, work up must be completed to exclude other etiologies prior to enrollment (i.e.Cushing's syndrome, androgen-secreting tumor)