Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder affecting 4-8% of reproductive-aged women and is a leading cause of infertility due to oligo-anovulation (1). Studies suggest a higher prevalence of 17.8-19.9% based on Rotterdam diagnostic criteria. PCOS is diagnosed by the presence of at least two out of three criteria: oligo- and/or anovulation, hyperandrogenism, and polycystic ovaries, with other etiologies excluded (2). Clomiphene citrate (CC), a selective estrogen receptor modulator, has been the first-line treatment for inducing ovulation in anovulatory women with PCOS for decades. Approximately 80% of women resume ovulation with CC, but only 35-40% achieve pregnancy. About 15-40% of women are resistant to CC, defined as failure to ovulate after receiving a maximum dosage of 150 mg per day for 5 days starting on the third day of the menstrual cycle. For CC-resistant women, metformin, an insulin sensitizer, has been explored but shows limited effectiveness except in combination with CC. Gonadotropins are the standard treatment for CC-resistant PCOS but come with risks of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (3). Letrozole, an aromatase inhibitor, is another treatment option that prevents the conversion of androgens to estrogen, thereby increasing gonadotropin-releasing hormone (GnRH) secretion and promoting ovulation. Letrozole has shown superior ovulation and live birth rates compared to CC and is now recommended as the first-line treatment for anovulation in women with PCOS. It has comparable rates of OHSS and miscarriage to CC, but fewer relevant studies have compared it directly to laparoscopic ovarian drilling (LOD) (4). LOD is an alternative to gonadotropins for inducing ovulation in CC-resistant PCOS. It involves surgical intervention, which can be either unilateral or bilateral, and is effective without the risks of multiple pregnancies or OHSS. LOD also increases ovarian responsiveness to CC. Despite minimal morbidity, LOD can lead to tubo-ovarian adhesions and premature ovarian failure, although these risks are reduced by careful technique (5).

### Materials and Methods

**Design:** A randomized clinical study to evaluate and compare the effects of gonadotropins, Letrozole, and unilateral laparoscopic ovarian drilling in infertile women with PCOS. Conducted at Kasr El Aini Maternity Hospital, Cairo University, gynecological and infertility clinics.

**Patients:** The study includes infertile women aged 20-35 years with PCOS referred to the gynecology and infertility clinics of the Department of Obstetrics and Gynecology, Kasr Ainy Hospital, Cairo University. Women diagnosed with PCOS based on the Rotterdam criteria (ovulatory disturbance, hyperandrogenism, and the presence of more than 12 follicles, 2-9 mm in diameter, in each ovary by ultrasound examination) are randomly assigned to one of three groups: Letrozole (G1), Gonadotropin (G2), or Laparoscopic Unilateral Ovarian Drilling (G3), based on a computer-generated random number sequence. Side effects for each intervention are registered.

**Treatment Protocol:**

• Group I (G1): Letrozole 2.5 mg oral tablets, administered from the fifth day of menses for 5 days, repeated for up to six cycles.
• Group II (G2): Human menopausal gonadotropin (hMG) starts on cycle day three, 75 IU every other day, aiming for mono-ovulation. Monitoring through transvaginal ultrasound begins on cycle day nine. The hMG dose is adjusted based on follicular response. Cycles are cancelled for under or over-response.
• Group III (G3): Laparoscopic ovarian drilling with electrocautery (mixed current, monopolar electrosurgical needle, 4-point cauterization, each for 4 seconds, 40 W, 3 mm diameter, 4 mm depth) on one ovary.

**Follow-Up:** Patients will be monitored for six months post-intervention. Hormonal profiles will be reassessed at the end of the study period. Statistical analyses will be performed using Microsoft Excel 2007 and IBM SPSS version 22. A p-value <0.05 will be considered statistically significant.

Inclusion Criteria:

• Age 20 to 35 years
• Infertile woman diagnosed to have PCO according to Rotterdam criteria as ovulatory distrbance, hyperandrogenism and presence of more than 12 follicles, 2- 9 mm in diameter in each other by ultrasound examination
• Resistance to clomiphene citrate i.e failed to respond to clomiphene citrate dose up to 150 mg per day for at least 3 cycles
• BMI from18-30
• High LH/FSH ratio≥1.5 , LH level ≥10IU/l)

Exclusion Criteria:

• Extremes of age less than 20 years old or more than 35 years old
• Hormonal therapy and oral contraception for the past 3cycle
• Other causes of infertility including tubal , uterine and male causes .
• Pre-existing endocrine disease including thyroid disorder, cushing's syndrome and congenital adrenal hyperplasia
• Any previous version surgery
• Obese patients with BMI >35
• Low ovarian reserve by AMH serum level measurement (AMH < .5-1.1 ng/ml).

infertile women from 20 to 35 years old with PCOS referred to gynecology and infertility clinics, Department of Obstetrics and Gynecology,Kasr Ainy Hospital , Cairo University. Infertile woman diagnosed to have PCO according to Rotterdam criteria as ovulatory disturbance, hyperandrogenism and presence of more than 12 follicles, 2- 9 mm in diameter in each other by ultrasound examination