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Overview of ovulation induction

Bart CJM Fauser, MD, PhD
Section Editors
Robert L Barbieri, MD
William F Crowley, Jr, MD
Deputy Editor
Kathryn A Martin, MD


Ovulatory disorders can be identified in 18 to 25 percent of couples presenting with infertility [1]. Most of these women have oligomenorrhea, arbitrarily defined as menstruation that occurs at intervals of 35 days to 6 months. While ovulation may occasionally occur, spontaneous conception is unlikely.

This topic will review the efficacy of the different regimens used for ovulation induction in women with ovulatory disorders (clomiphene citrate, gonadotropins, pulsatile gonadotropin-releasing hormone [GnRH] therapy, aromatase inhibitors, and dopamine agonists) and provide our approach to the management of such women. Some of these drugs are reviewed in greater detail elsewhere, and assisted reproductive technologies are also discussed elsewhere. (See "Ovulation induction with clomiphene citrate" and "Ovulation induction with letrozole" and "In vitro fertilization".)


The clinical approach to ovulation induction requires an understanding of the causes of anovulation. The World Health Organization (WHO) classified different categories of anovulation into three categories:

WHO class 1: Hypogonadotropic hypogonadal anovulation (hypothalamic amenorrhea [HA]) (see "Evaluation and management of secondary amenorrhea" and "Functional hypothalamic amenorrhea: Pathophysiology and clinical manifestations")

WHO class 2: Normogonadotropic normoestrogenic anovulation (almost all women in this category have polycystic ovary syndrome [PCOS]), when using the Rotterdam criteria for the diagnosis of PCOS [2] (see "Diagnosis of polycystic ovary syndrome in adults", section on 'Diagnosis')

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Literature review current through: Oct 2017. | This topic last updated: Nov 28, 2016.
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