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Updated: Aug 18, 2026

Culture and Co-Culture of Mouse Ovaries and Ovarian Follicles
Published on: March 17, 2015
A new model for ovarian follicular development during the human menstrual cycle
Angela R Baerwald1, Gregg P Adams, Roger A Pierson
1Women's Health Imaging Research Laboratory, Department of Obstetrics, Gynecology and Reproductive Sciences, University of Saskatchewan, Saskatoon, Saskatchewan, Canada. baerwald@erato.usask.ca
Objective:
To evaluate changes in ovarian follicle dynamics during the human menstrual cycle to test the hypothesis that folliculogenesis occurs in a wave-like fashion.
Design:
Prospective longitudinal study.
Setting:
Healthy volunteers in an academic research environment.
Patient(S):
Fifty healthy women of reproductive age (range 19-43 years) with a history of regular menstrual cycles not taking medications known to interfere with reproductive function were evaluated.
Intervention(S):
Transvaginal ultrasonography was performed daily for one interovulatory interval (IOI).
Main Outcome Measure(S):
Changes in the diameter and number of follicles > or =5 mm were evaluated.
Result(S):
Sixty-eight percent of women exhibited two waves of follicle development during the IOI and 32% exhibited three waves. Waves were characterized by an increase and subsequent decrease in the number of follicles > or =5 mm occurring in association with the growth of > or =2 follicles to > or =6 mm. A day effect and day by wave interaction were detected in the mean diameter of the largest three follicles and the number of follicles > or =5 mm.
Conclusion(S):
The follicular wave phenomenon in women provides a new model for ovarian function during the menstrual cycle and will improve our understanding of the ovarian response to fertility and hormonal contraceptive regimens.
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