Aromatase Inhibitors in Ovulation Induction

The new third generation aromatase inhibitors are extremely potent and specific oral inhibitors of estrogen production. We reported the success of using aromatase inhibitors for induction of ovulation in World Health Organization (WHO) type II anovulatory patients. Promising pregnancy rates were associated with the use of aromatase inhibitors for induction of ovulation in these women. In addition, the use of aromatase inhibition in conjunction with gonadotropin injection was associated with a significant reduction in the gonadotropin dose required for optimum controlled ovarian hyperstimulation. We believe that these oral agents are efficient and safe and have many advantages compared with clomiphene citrate (CC). We propose that aromatase inhibitors will replace CC in the future as the new primary treatment for ovulation induction. In this review, we present an update on the use of aromatase inhibitors for induction of ovulation and we discuss several new areas of potential interest regarding the use of aromatase inhibitors, either alone or together with recombinant follicle-stimulating hormone (FSH) for infertility treatment. Further research in these areas may demonstrate an expanded role in assisted reproductive technologies.

KEYWORDS

Aromatase inhibitors - induction of ovulation - FSH - polycystic ovary syndrome - assisted reproduction

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