By Plum – The Pregnancy & Parenting Guide for Women
When do you really need to start paying attention to the biological clock’s alarm? “It’s different for every woman,” says Karine Chung, MD, founder and director of the University of Southern California’s Fertility Preservation Program. But in general, your risk factors start rising in your late 20s and really pick up speed in your mid-to-late 30s. There are no guarantees — you might lose the ability to conceive easily at 25, or you might keep it until you are 45.
The key culprit is your eggs. Eggs decline in both quantity and quality as you age. You’re born with a certain number of eggs and that number shrinks every month when you ovulate. Meanwhile, as the remaining eggs age, many of them will deteriorate at a cellular level, throwing the composition of their generic material out of balance.
Taken together, those factors mean that the older you are, the less likely you are to get pregnant, and the more likely you are to have complications if you do. The chance that you are infertile is about nine percent at age 25, more than double that at age 35, and hits 29 percent by age 40, according to the American Society of Reproductive Medicine.
There are several tests that can estimate your fertility by gauging the size and quality of your stockpile of eggs. These include testing your blood levels of follicle stimulating hormone (FSH) — the stuff that gears up your ovaries to kick out an egg — and using ultrasound to assess the number of eggs you have left. New tests, of course, are always coming out. Repromedix Corp. rolled out a new blood test this January that measures FSH along with several other hormones. And in May of 2007, the first do-it-yourself version, made by the Fertell company, hit drugstore shelves; it measures levels of FSH in a woman’s urine.
Chung cautions against relying on them, however. “Your FSH levels fluctuate month to month,” she says, “so just looking at a single test result without a doctor to put it in perspective could make a woman feel unjustifiedly reassured or panicked.” There’s no truth to the myth that the age of your first period gives a clue to your fertility, says the ASRM’s Dr. Fritz. But if your mother hit menopause at an early age, you’re at risk of that as well.