Serum FSH Monitoring for Identification of an Optimal Range During Ovarian Stimulation

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