Woman’s Biologic Clock

We believe that every woman needs the facts about her biological clock. Start here to learn more about fertility age and how time really affects your ability to have a healthy baby.

Not every egg leads to a baby, no matter how young you are. It’s a common misconception that we have a 100% chance of pregnancy each time we ovulate (i.e., each month). Because a certain percentage of our eggs are abnormal at any age, and because fertilization has to happen within a narrow window after ovulation occurs, even a young, healthy woman trying to get pregnant has only about a 20% chance each month.

Fertility goes into a sharper decline around age of 35 – over 10 years before reaching menopause. As women, our reproductive life begins when we get our first period, usually around age 12 (puberty), and lasts until our last menstrual period, usually around age 52 (menopause). But because egg count (ovarian reserve) and egg quality decline as we age, we don’t remain fertile for the entirety of this timespan.

Women under the age of 35 have about a 20% chance of getting pregnant naturally each cycle. By the age of 40, the chance of getting pregnant naturally each month is just 5%. After that, natural conception declines faster.

In fact, statistics from scientific research for women undergoing In Vitro Fertilization (IVF) shows that pregnancy rate also declines with advanced age. IVF pregnancy rate in women below the age of 35 may range from 40-50% and it decreases to 30% by age of 40 and it declines even more after age of 43 to less than 5%.

As you age, the DNA inside your eggs begins to degrade. Because your eggs have been with you since before you were born, they are exposed to all sorts of damaging, but mostly unavoidable, influences throughout our lives: fevers, infections, stress, toxins, and free radicals. Because eggs are fragile and easily damaged, this exposure can lead to chromosomal abnormalities which affects their abilities to produce normal embryos ready for implantation and occurrence of pregnancy.

There is no test for egg quality. The only way to know if an egg is chromosomally normal is to attempt to fertilize it outside the body, and, if fertilization is successful, to perform a genetic test on the embryo. But because damage to our DNA happens naturally and inevitably over time, your age can give a fairly accurate picture of what percentage of your eggs are normal.

This is a fact

Because age directly correlates with egg quality, and therefore the ability of the egg to fertilize into a healthy pregnancy, it’s the age of the egg that matters most when it comes to fertility. Seeking help for fertility treatment at younger age makes it much more meaningful.

If you are ready to get proactive about your fertility future, you can schedule a fertility assessment today at Bnoon Medical Center to meet one of our fertility experts.