Women have a biological clock. Everyone knows that. The problem is that a lot of the information people think they know about their fertility and reproduction is not true. The blurring of fact, opinion, myth, and misunderstanding makes for a treacherous misinformation landscape. The knowledge gap has claimed millions of victims, people who learned about their limited reproductive lifespan too late to help them have genetically linked offspring they always assumed would be theirs. Armed with essential and accurate information, you don’t have to join their ranks.
What is still not understood across the board is the time line of the biological clock. And most women don’t have a clue about their own.
So the big question is—what do you know about your fertility?
Well, if you’re like most people, the answer is not as much as you might believe. Just to give you a little perspective, a spate of recent surveys reveals that the overwhelming majority of U.S. women:
- Don’t understand the biological clock—the trajectory of reproductive capabilities from its peak in the early-to-mid-twenties to the age of inevitable decline beginning, typically, around twenty-seven.
- Mistake overall good health for an indicator of fertility. However wonderfully youthful and fit a forty-two-year-old might be, her eggs are operating on an independent and fixed timeline.
- Believe they can get pregnant easily until their forties. The stark truth is women at that age are more likely than not to require medical intervention.
- Don’t know that lifestyle factors—sleep, diet, exercise, and environment, for instance, can have a profound effect on the ability to have a child.
Yet this basic information can make a critical difference in the life of every person who dreams of having a child. If you know about your body’s reproductive lifecycle, you can take steps to protect and preserve your fertility. Then you can have the children you want—if and when you choose.
Statistics and general truths aside, every woman is unique. Given just how complicated it is to make a baby in the first place, understanding your own body’s reproductive capability and the changes it might undergo from year to year, is an invaluable planning tool. Consider an annual fertility evaluation or screening.
Simply put, the screening involves a few simple blood tests and an ultrasound to assess your ovarian function. These tests have been around for years, tried and true tools in the assessment of fertility. We are proposing using these tests as a screen to prevent future infertility.
Taken together with your individual and your family’s medical histories, the screening helps establish where you are on your personal fertility curve. The first screening establishes your baseline; subsequent annual evaluations will flag changes in key hormone levels and mature follicle and egg production that could signal potential trouble. Mind you, any warning flares are just that and may mean nothing. But they could indicate that follow-up with your doctor, gynecologist or a reproductive specialist is warranted. And if there is problem, you’re ahead of the game with the opportunity for early intervention and, where possible, corrective action.
Marking Time: The Biological Clock and You
Each woman’s oocytes (eggs) supply is finite. That means the body doesn’t produce new ones. So the 7 million or so eggs each female is born with is all she’s going to have. By the time the average girl hits puberty, only about 250,000–300,000 oocytes remain in her ovaries. With each menstrual cycle one egg is released, and an additional thousand eggs each month are lost through a process called artresia, the natural breakdown of the eggs by the body. After ovulating an average of 400 times through her life, typically at around fifties years of age, the store of oocytes is tapped out. That’s menopause.
Then there’s the matter of oocyte aging. Eggs age along with the rest of the body. The older oocytes are more likely to have chromosomal abnormalities making them unlikely to become viable embryos. It’s important to note that a fertilized egg with abnormal chromosomes is the single most common cause of miscarriage. As a general rule, women in their 20s have about a 20 percent chance of having a miscarriage each time she becomes pregnant, a woman in her 30’s a 30 percent chance and a woman in her 40s about a 40 percent risk of miscarriage.
The bottom line is the older we get, the less likely we are to conceive and have a successful pregnancy. Fertility starts to decline when a woman is in her 20s but when she hits 35, it take a sharp downturn. At 40, fertility falls off even more dramatically.
Of course, some women in their late 30s and a few in their 40s conceive effortlessly, carry and deliver healthy babies. But the likelihood of that happening without medical intervention becomes more remote with each passing year. For women under 30, the estimated chance of becoming pregnant in any one cycle is between 20 percent and 30 percent. When women turn 40, that probability plummets to approximately 5 percent. Even more significant is that when a woman experiences difficulty conceiving in her 40’s it is a far greater challenge to achieve a live birth using her own eggs even with the best medical technologies.
A positive screen showing evidence of potentially diminishing fertility is an alarm that should produce a call to action. When a woman is aware that she may be running out of time to reproduce she can take the family-planning reins and make informed decisions. The goal of fertility screening is to help you and every woman of childbearing years make the choices that can help protect and optimize your fertility.
Fertility Screening for Your Reproductive Life
Fertility screening is an important tool to help you identify where you are on your own fertility curve. Perhaps even more important, the screening can help identify women whose ovarian function is diminishing so they can get timely treatment. The fact is, some women in their 30’s prematurely age from a reproductive perspective and their fertility may resemble more like women in their 40’s than women their same age.
The screening itself is fairly low-tech. Part one consists of a blood test to check the levels of FSH (follicle stimulating hormone), estradiol and AMH (antimullerian hormone). The FSH and estradiol must be measured on the second or third day of your period. The granulosa cells of the ovarian follicles produce estradiol and AMH. The fewer the follicles there are in the ovaries the lower the AMH level. It will also mean that less estradiol is produced as well as a protein called inhibin. Both inhibin and estradiol decrease FSH production. The lower the inhibin and estradiol the higher the FSH as is seen in diminished ovarian reserve. The higher the estradiol or inhibin levels are then the lower the FSH. Estradiol may be elevated especially in the presence of an ovarian cyst even with failing ovaries that are only able to produce minimal inhibin. However, the high estradiol reduces the FSH to deceptively normal appearing levels. If not for the cyst generating excess estradiol, the FSH would be high in failing ovaries due to low inhibin production. This is why it is important to get an estradiol level at the same time as the FSH and early in the cycle when it is likely that the estradiol level is low in order to get an accurate reading of FSH.
Part two is a vaginal ultrasound to count the number of antral follicles in both ovaries. Antral follicles are a good indicator of the reserve of eggs remaining in the ovary. In general, fertility specialists like to see at least a total of eight antral follicles for the two ovaries. Between nine and twelve might be considered a borderline antral follicle count.
What you and your doctor are looking for is a dramatic shift in values from one year to the next.
Although none of these tests is in of and of themselves an absolute predictor of your ability to get pregnant, when one or more come back in the abnormal range, it is highly suggestive of ovarian compromise. It deserves further scrutiny. That’s when it makes sense to have a discussion with your gynecologist or fertility specialist. Bear in mind, the “normal” range is quite broad. But when an “abnormal” flare goes off, you want to check it out.
It’s important to remember that fertility is more than your ovaries. If you have risk factors for blocked fallopian tubes such as a history of previous pelvic infection, or if your partner has potentially abnormal sperm, then other tests are in order. And if, for example you do have blocked tubes, it’s better to have them corrected sooner rather than later when the becoming pregnant is an urgent matter.
We recommend that annual screening begin at 30 years of age and earlier if you have irregular menses, hot flashes, difficulty conceiving after 6 months or a family history of early menopause or infertility.
Fertility Preservation: The Egg Freezing Revolution and The Biological Clock
As so many women discovered late in life, procreation is a far more delicate and complicated process than most of us ever suspect. After all we spend so much time trying to avoid pregnancy, it never occurs to us that we may not be able to when we want.
So what do you do if you are in the midst of getting your degree or your career is on an upward trend that you don’t want to derail? Until recently, the options were few and unreliable.
But the world of reproductive medicine is on the fast track to breakthroughs in egg freezing which is giving young women the opportunity to put the best of their oocytes into a safe deep freeze until they’re ready to use them.
Some IVF Centers claim that they are ready to provide state of the art egg freezing right now to women with hundreds of healthy babies already born. Others, like East Coast Fertility, are in the midst of doing studies and offering discounts to patients who want to be a part of the Egg Freezing Studies.
With careful attention to your fertility through a program of annual fertility screening, early intervention with fertility treatment or egg freezing, we can eliminate most cases of infertility due to aging and diminishing ovarian reserve.
Written by Dr. David Kreiner, Reproductive Endocrinologist, Founder and Medical Director of East Coast Fertility in New York. Originally published on FertilityTies.com