Related Experiment Video
Updated: Oct 1, 2026

Exploring Independent Effects of Follicle-Stimulating Hormone In Vivo in a Mouse Model
Published on: August 11, 2023
Urinary follicle-stimulating hormone peak as a biomarker for estimating the day of ovulation
Hongxia Li1, Jiangang Chen, James W Overstreet
1Center for Health and the Environment, School of Medicine, University of California, Davis, Davis, California 95616-8739, USA.
Objective:
To evaluate urinary follicle-stimulating hormone (FSH) as a biomarker for the day of ovulation.
Design:
Prospective observational study.
Setting:
Clinical research center.
Patient(S):
Thirteen women were monitored with measurements of serum and urinary hormones and ovarian ultrasonography during 20 menstrual cycles. Data on urinary hormones and ultrasound evaluations from a total of 65 menstrual cycles from 42 women were analyzed.
Intervention(S):
Blood and/or urine samples were collected daily. Daily transvaginal ultrasonography was used to detect follicular collapse.
Main Outcome Measure(S):
LH, FSH, and E(2) were measured in serum. FSH, estrone conjugates (E1C), and pregnanediol-3-glucuronide (PdG) were analyzed in urine. The day of luteal transition (DLT) was calculated using two algorithms.
Result(S):
In 20 cycles, the urinary FSH peak was closer to the day of follicular collapse (-0.85 days) than was the peak day of serum E(2) and the day of luteal transition, as calculated by one algorithm. The FSH peak was not closer to the day of follicular collapse than the peak values of urinary LH, serum FSH, or the day of luteal transition as calculated by a second algorithm. The most consistent correspondence between a hormone peak and ovulation was for serum E(2), serum FSH, serum LH, and urinary FSH. In 65 cycles for which urinary hormone data and ultrasound evaluations were available, the urinary FSH peak occurred within 1 day of follicular collapse in 97% of cycles.
Conclusion(S):
Urinary FSH is a useful biomarker for estimating the day of ovulation in population-based studies.
More Related Videos
Related Concept Videos
Ovarian Cycle
Hormonal Control of the Ovarian Cycle
Before puberty, the hypothalamus releases GnRH in a low frequency, low amplitude pulsatile manner. This along with the immature hypothalamic-pituitary-gonadal axis activity, results in low estrogen levels and the absence of a fully functional ovarian cycle. At puberty, GnRH secretion increases in both frequency and...
Folliculogenesis
Proliferative Phase
Notably, the stratum basale, the basal layer of the endometrium, including the basal parts of the uterine glands, remains unaffected by menstruation. Stem cells in this layer undergo mitosis, regenerating the stratum functionalis and thickening the...
Hormonal Regulation of the Menstrual Cycle
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH release.
Secretory Phase
Following ovulation, the corpus luteum, a temporary endocrine structure, produces progesterone and estrogens. These hormones stimulate the growth and coiling of endometrial...

