Women who want to postpone pregnancy but are still keen to conceive naturally without having to resort to infertility treatment
may be interested in a new study by US scientists.
For the average woman, natural fertility appears to decline quite rapidly after the age of 35; yet many are keen to delay becoming a mother for as long as possible for personal or career reasons.
Researchers at the University of Michigan believe it may soon be possible to tell if a woman is approaching menopause by looking at levels of her hormones.
They found that levels of a hormone called anti-Mullerian hormone (AMH) decline significantly five years before a woman has her last period.
At this stage, according to lead researcher Professor MaryFran Sowers, a woman probably has barely enough eggs to still be fertile.
The team also found that, by measuring levels of another hormone called follicle-stimulating hormone (FSH), it is possible to identify four different stages from the late reproductive period to the time of a woman's final period.
"The information provides a roadmap as to how fast women are progressing through the different elements of their reproductive life," said Professor Sowers.
The expert noted that women want to know how much time they have left before they reach menopause.
"We finally have numbers from enough women evaluated over a long time period to describe the reproductive aging process," she concluded.
The findings are published in the Journal of Clinical Endocrinology and Metabolism.