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Updated: Aug 19, 2026

OP-IVM: Combining In vitro Maturation after Oocyte Retrieval with Gynecological Surgery
Published on: May 9, 2021
Exogenous gonadotropin therapy in World Health Organization groups I and II ovulatory disorders
M R Fluker1, B Urman, M Mackinnon
1Department of Obstetrics and Gynecology, University of British Columbia, Canada.
Objective:
To analyze cumulative conception rates and the prognostic factors influencing them during exogenous human menopausal gonadotropin (hMG) therapy for World Health Organization (WHO) group I or II ovulatory disorders.
Methods:
A retrospective review was conducted of 468 treatment cycles in 146 women with ovulatory disorders refractory to conventional therapy. Cumulative conception rates were calculated, and the effects of diagnostic group, age, gravidity, and duration of infertility were examined using the Cox proportional hazards model.
Results:
The cumulative proportion pregnant following six hMG cycles in WHO group I (0.89) was significantly greater than in the hyperandrogenic subgroup of WHO group II (0.30) (95% confidence interval [CI] 0.2-0.7, P = .006) or the luteal phase defect subgroup (0.35) (95% CI 0.07-0.6, P = .02). Conception rates in WHO group I did not differ significantly from those in the normoandrogenic oligo-ovulatory subgroup of WHO group II (0.63) (95% CI 0.3-1.3, P = .6). Conception rates were not influenced by duration of infertility or primary versus secondary infertility. Women 35 years or older had significantly lower conception rates than those aged 27 years or less (P = .04, hazard ratio 0.3, 95% CI 0.1-0.8).
Conclusions:
Cumulative conception rates following exogenous gonadotropin therapy for women with refractory ovulatory disorders were both diagnosis- and age-dependent. Treatment with hMG approximated or surpassed normal fertility rates in women with WHO group I and normoandrogenic WHO group II oligo-ovulation, but was significantly less successful at correcting the underlying defect in women with hyperandrogenic anovulation and luteal phase defects.
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