Impact of Age and Ovarian Reserve on Pregnancy

In recent years, age-related infertility has become a common issue affecting women in the US. Many people are choosing to have children later in life, choosing to wait until their 30s to start a family.  Even though women today are healthier and take better care of themselves, they still have a harder time getting pregnant as they age. Fertility declines as a part of the natural aging process, which is unrelated to a healthy lifestyle.

As age increases, a woman’s ovarian reserve decreases. Low ovarian reserve indicates reduced egg quantity and is also a sign that the quality of the remaining eggs has declined. Chromosomal abnormalities also become more common with age. Together, these factors mean that older women have lower pregnancy rates and higher rates of miscarriage.

Age & Fertility

Fertility changes for both males and females as they age, but at different rates. According to the American Society for Reproductive Medicine (ASRM), a woman’s fertility peaks in her 20s and starts to decline in her 30s, especially after age 35. Information collected by the CDC shows that around one-third of couples in which the woman is older than 35 have fertility problems. However, each person is unique and the exact age when a woman can no longer conceive varies.

It is a common misconception that women remain fertile until they reach menopause and stop menstruating. In reality, most women will lose fertility 5 to 10 years before menopause. For instance, the average age for menopause is 51, while most women lose the ability to conceive in their mid-40s.

Testing for Fertility and Ovarian Reserve

There are several different tests used to determine a woman’s fertility potential or ovarian reserve. Ovarian reserve is how many eggs are remaining in the ovaries. Physicians start with blood tests to evaluate levels of hormones that indicate how the ovaries are functioning. Common hormone levels checked with blood tests include follicle-stimulating hormone (FSH), estradiol and anti-müllerian hormone (AMH). 

FSH and estradiol levels are checked at the beginning of a woman’s menstrual cycle. These are usually conducted on day 3 of the cycle but can be drawn from day 1 to day 5. The levels of these hormones allow doctors to evaluate how well the ovaries and pituitary gland are working together. FSH levels are low at the beginning of a cycle and increase as the cycle progresses, causing follicle growth and allowing the egg to mature. If FSH is too high at the beginning of the cycle, the egg does not mature properly, making pregnancy less likely.

Testing AMH levels is the best way to evaluate ovarian reserve. These tests can be drawn at any point in the menstrual cycle. AMH is produced in ovarian follicles and can be used to estimate the number of eggs remaining in the ovaries. AMH levels are higher when there are more eggs remaining. A typical AMH level for a fertile woman is 1.0–4.0 ng/ml and AMH level under 1.0 ng/ml is considered low. 

It is important to keep in mind that no single test can conclusively indicate a woman’s ovarian reserve. A comprehensive picture of the ovarian reserve should be formed using factors like age and the results of multiple appropriate testing.

When to See a Fertility Specialist

For women under 35, infertility is diagnosed if they have not conceived after one year of unprotected intercourse. If you are 35 or older, then you should see a reproductive endocrinologist for an evaluation after 6 months of unprotected intercourse. 

Women who have a medical condition that could make conceiving difficult, then you should be evaluated by a fertility specialist as soon as you decide you want to start trying to get pregnant. Conditions that may make lead to difficulty conceiving include:

  • Irregular menstrual periods that suggest you are not ovulating
  • Endometriosis
  • Diagnosed polycystic ovarian syndrome
  • Sexual dysfunction
  • A history of pelvic disease
  • Prior surgeries that may affect fertility
  • Your partner has a known fertility issue

At Laurel Fertility Care, we are dedicated to helping families grow. Our team is committed to developing a treatment plan that works for your individual circumstances. This includes taking into account health issues, causes of infertility, and financial limitations. If you have questions or concerns on the impact of age and ovarian reserve on pregnancy, call us at (415) 673-9199 to make an appointment