Related Experiment Video
Updated: Aug 24, 2026
Human Egg Maturity Assessment and Its Clinical Application
Published on: August 19, 2019
Mature oocyte retrieval without an exogenous trigger during random-start stimulation in a very early intrauterine
Mohammad Saaed ElFarran1, Karolina Palinska-Rudzka1, Raj Mathur1
1Department of Reproductive Medicine, Manchester University NHS Foundation Trust, Manchester, United Kingdom.
Objective:
To describe a rare case of mature oocyte retrieval without an exogenous trigger during random-start controlled ovarian stimulation (RS-COS) coinciding with a very early intrauterine pregnancy.
Design:
Case report.
Subject:
A 32-year-old para 1 patient with inflammatory breast cancer (grade 3, T4N2M0, ER/PR negative, HER2 3+, Ki-67 60%).
Exposure:
Luteal-phase RS-COS using a gonadotropin-releasing hormone antagonist protocol with human menopausal gonadotropin (hMG) 300 IU daily. Egg retrieval was performed on day 12 after stimulation.
Main Outcome Measures:
Number and maturity of oocytes retrieved; occurrence of ovarian hyperstimulation syndrome (OHSS).
Results:
On day 10 of stimulation, 25 follicles measuring ≥12 mm were seen, of which 18 were in the right ovary. A gestational sac was seen in the uterine cavity. The serum human chorionic gonadotropin level was 2,563 IU/L. Oocyte retrieval from the right ovary was performed without administering a trigger. Nine metaphase II oocytes were retrieved and vitrified; mild clinical OHSS occurred.
Conclusion:
This case demonstrates that it may be possible to perform COS in early pregnancy and be able to retrieve mature oocytes without the use of an exogenous trigger. To our knowledge, there are no previous published reports of multiple metaphase II oocyte retrieval without an exogenous trigger during RS-COS.
