This study examines if monitoring serum Follicle Stimulation Hormone (FSH) levels can predict oocyte yield and progesterone levels, considering factors like age, baseline FSH, Antral Mullerian Hormone (AMH), antral follicle count, body weight, kidney function, and urinary FSH. The aim is to find a minimum FSH level that ensures optimal ovarian response and enables tailored FSH dosages for better outcomes.

Ovarian stimulation typically uses transvaginal ultrasound to monitor follicle growth and endometrial condition, with some clinics also tracking serum estradiol and progesterone levels, but often neglecting serum Follicle Stimulation Hormone (FSH). FSH is essential for follicle development, yet its levels can vary widely among women receiving the same dose due to factors like body weight, renal function, and ovarian reserve.

This study aims to identify a minimum effective FSH threshold that ensures optimal follicular growth while avoiding excess administration.

Inclusion Criteria:

• regular 21 - 35 days cycles
• BMI between 19 - 30 kg/m2
• serum AMH level between 1.5 to 3 ng/ml
• a total antral follicle count between 10 to 24
• endogenous early follicular phase serum FSH level <10 IU/L
• normal glomerular filtration rate

Exclusion Criteria:

• hypogonadotropic hypogonadism
• history of ovarian surgery
• permanent ovarian cysts of any form
• older than 39 years
• abnormal thyroid stimulating hormone (TSH)
• renal disease
• elevated prolactin levels
• intake of oral contraceptives 3 months before stimulation start and estradiol pretreatment will be excluded

Women between 18 and 39 years old, with regular 21 - 35 days cycles, BMI between 19 - 30 kg/m2, serum AMH level between 1.5 to 3 ng/ml, a total antral follicle count between 10 to 24, endogenous early follicular phase serum FSH level <10 IU/L, normal glomerular filtration rate who is planned to undergo ovarian stimulation in a Gonadotropin hormone-releasing hormone (GnRH) antagonist protocol can be included.

Exclusion will be for women with hypogonadotropic hypogonadism, history of ovarian surgery, permanent ovarian cysts of any form, older than 39 years, abnormal thyroid function (TSH level outside the normal range), renal disease, elevated prolactin levels. intake of oral contraceptives 3 months before stimulation start and estradiol pretreatment will be excluded.

on request