High FSH and Low AMH does not predict your fertility

AMH (anti-mullerian hormone) and FSH (follicle stimulating hormone) are routine fertility tests done to determine a women’s ovarian reserve. Ovarian reserve testing has been used to predict a women’s fertility potential, egg quality, and responsiveness to assisted reproductive techniques (IVF, IUI, etc).

A study published in the Journal of the American Medical Association from the University of North Carolina shows that ovarian reserve testing does not predict fertility as well as they thought.

The study evaluated 750 women, aged 30-44 years, who have been trying to conceive naturally for 3 months or less (not infertile, which is defined as trying to conceive for more than 12 months). The women were evaluated for AMH, FSH, urinary FSH and inhibin B (another marker of ovarian reserve used less often) for up to 12 months.

They found that women with diminished ovarian reserve (AMH < 0.7ng/mL or FSH >10mIU/mL) had similar chances of conceiving compared to women with normal ovarian reserve.

Women with low AMH had an 84% cumulative probability of conceiving by 12 cycles of pregnancy compared to 75% of women with normal AMH (>0.7ng/mL - 8.4ng/mL), a nonsignificant difference. Women with serum FSH levels below 10mIU/mL had an 75% chance of conceiving compared to 82% of women with FSH levels above 10mIU/mL.

It is known that both ovarian reserve and fertility decline with chronological age. According to this study, there may be other factors to consider other than ovarian reserve that affect one’s fertility, such as egg quality.

Selective follicular recruitment could also occur in women with low AMH levels, meaning a greater proportion of the remaining follicle pool activate and become growing follicles. It has also been shown that women of advanced maternal age (higher FSH) are at risk of dizygotic twins, due to “super ovulation” with multi follicular ovulation, increasing the odds of pregnancy.

Women should be cautioned against using AMH and FSH levels to assess their current fertility.

Hormone testing can be very informative when used in the right context. It is important to look at all aspects effecting your fertility and to not let numbers dictate your decisions.

In good health,

Dr. Kirti Deol