Topic Overview

From birth, females have a fixed—though plentiful—supply of eggs (ovarian reserve). As a woman ages past her mid-30s, her eggs gradually degrade, making it less likely that she will naturally conceive, or that an assisted reproductive technology (ART) procedure will result in pregnancy and a healthy baby.

Among Canadian women younger than 35, 38 out of 100 give birth for each ART cycle . As women age, the live ART birth rate gradually drops:footnote 1

  • To 28 out of 100 for women ages 35 to 39.
  • To 11 out of 100 for women 40 and older.

Many women over age 40 choose to use donor eggs, which greatly improves their chances of giving birth to a healthy child.

While there is no definitive test of ovarian reserve, a woman's follicle-stimulating hormone (FSH) level can be measured to evaluate how well her ovaries are working. A high FSH level is a sign that the body is trying to stimulate the ovaries to make more egg follicles, but the ovaries are not responding and conception is unlikely.

A woman's FSH level can be tested using a blood sample:

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  1. Canadian Fertility and Andrology Society (2013). Human assisted reproduction 2013 live birth rates for Canada. Canadian Fertility and Andrology Society. Accessed December 19, 2013.


ByHealthwise Staff
Primary Medical Reviewer Kathleen Romito, MD - Family Medicine
Anne C. Poinier, MD - Internal Medicine
Specialist Medical Reviewer Femi Olatunbosun, MB, FRCSC - Obstetrics and Gynecology

Current as ofMay 22, 2015