health & beauty

FERTILITY 101

Baby Now? Baby Later?

By Rachel Oosterbaan, MD • Photography by Barb Levant

If you're confused by the conflicting information regarding fertility these days, you're not alone. One day you're being told to hurry up and have kids before it's too late; the next, you're being warned about the dangers to your career if you have a family too early. Our advice? Relax, get the facts, then make the right choice for you.

FACT AND FICTION

Delaying pregnancy – whether to pursue a career or for other personal reasons – is a common choice for women in today's society. Of course, the harsh reality is that women don't have forever if they want to have children, plain and simple. You still have options; you just have to be well-informed. If you want to have it all, you need to be smart about it.

There are many misconceptions about fertility, but three seem to be the most common. First, woman frequently feel like they have plenty of time to get pregnant; we hear about women all the time in the news who get pregnant for the first time in their 40s. While this does happen, the reason why you hear it on the news is that it is, in fact, newsworthy! This is rare and difficult, and oftentimes the celebrity who got pregnant in her 40s actually used donor eggs.

We may be in the 21st century with a lot of advancements in technology, but biology is biology. At birth, we are born with a finite number of eggs.

Those eggs continue to decline in number and quality as we get older, until there are no more quality eggs in our reserve. As we age, the quality of aging oocytes (eggs) declines, resulting in chromosomal and functional abnormalities, as well as birth defects such as Down's syndrome. In addition, the ovarian reserve declines, resulting in less eggs and longer time to conception, and the hormonal environment is altered, leading to ovulatory dysfunction. All of these changes decrease our fertility. Only five percent of women with diminished ovarian reserve will achieve pregnancy, despite the use of an ovulation-inducing agent. In addition to ovarian factors, older women have had more opportunity to acquire conditions such as endometriosis, fibroids, endometrial polyps, scarring in their fallopian tubes and pelvic infections, all of which can impair fertility.

Assisted Reproductive Therapy (ART) methods such as intrauterine insemination (IUI) and in vitro fertilization (IVF) for age-related infertility can decrease the time it takes to conceive, but they don't affect egg quality. Although these treatment options improve the likelihood of achieving pregnancy, ART cannot compensate for the natural decline of fertility associated with advancing age and aging eggs. The truth is, a woman's fertility at age 34 is 40 percent less than what it was at age 25. Roughly, the percentage of live births is 30 percent between ages 35 to 37, 20 percent between ages 38 to 40, 10 percent between ages 41 to 42 and a whopping 4 percent over the age of 42. Don't forget that other complications occur more frequently as we get older, such as chromosomal abnormalities, as well as complications with pregnancy, including gestational diabetes and preeclamsia. (Biology doesn't discriminate, either; men's fertility declines in middle age as well. Fortunately for them, they still continue to produce and develop new sperm throughout their lifetime, mitigating the concern regarding a time limit on the ability to procreate.)

Woman should know there are blood tests available to determine their ovarian reserve, which in turn reflects their age-related fertility potential. The simplest test is done by measuring the follicular stimulating hormone (FSH) and estradiol level on day three of a woman's menstrual cycle. Generally, if the FSH concentration is a less than 15 mIU/ml, she is considered to still have an adequate ovarian reserve. This simple test will at least guide a woman in making decisions about her fertility and whether IUI and IVF are viable options.

A second misconception often comes from the woman who is 35 or older and engaged to be married; she may plan to use birth control for a couple years before starting a family so that they can have fun, buy a house, et cetera. But the truth is, if you're over 35 years of age and consider having a family a priority, you probably should stop the birth control on the way down the aisle. This may sound a little alarmist, but after the age of 35, your egg reserve and quality markedly decline. As a result, it's not as easy as you think to get pregnant. Delaying pregnancy can decrease the probability of successful conception; older couples should begin fertility treatment sooner and consider more aggressive treatment than younger couples.

Lastly, single women in their late 30s often state that perhaps they should just freeze their eggs. This option has gotten a lot of ink in the press lately, and as a result, there's a misperception that it's a well-established practice. Again, not so simple! At this point in time, this process is mostly used for women who have cancer and are going to undergo some treatment such as chemotherapy that will jeopardize their eggs, so they have them frozen for a later date. However, for the average woman to think she can just save her eggs for a later date, there are a few things to consider. Cryopreservation of oocytes (science-speak for freezing your eggs) is an investigational procedure that is becoming an option for women without partners who do not opt to use donor sperm for IVF. Therefore, although freezing eggs for the purpose of insemination at a later date can be successful, there are still many inconsistencies in the technique and success rate. This makes egg freezing an option that is usually justified only in the setting of a medical imperative.

A more successful approach is to have a woman freeze an embryo, or fertilized egg. This would mean that this very same woman would have to have the foresight to not only freeze her egg, but also find a sperm and basically undergo in vitro techniques in order to save this embryo for a later date. The trouble with this procedure is the average single woman in her late 30s is waiting because she is hoping she'll find that partner with whom to have a child; having the foresight to actually have a frozen embryo is more successful but may defeat the purpose to begin with. As previously mentioned, because the egg quality and number does decline with older age, the decision to freeze anything really should be done by age 35 or the success rate markedly declines.

NOW, THE GOOD NEWS

Okay, now that you're good and stressed out, here's the good news: there are some factors on your side. Some fertility experts would make it seem that your only hope is to have your children in your 20s, but this isn't the case! The oldest natural pregnancy occurred in a 57-year-old woman, and there have been a lot of advances in the area of fertility. If you're trying to get pregnant and having difficulty, many diagnostic tests can be done to find the problem. Also, various medications such as clomiphene or FSH injections can help with stimulating ovulation and assisting with reproduction. Intrauterine and in vitro fertilization are also options that increase the rate of live births. It's simply important to stress to women and couples that you don't have forever to conceive a child. If you are over 35 and you want a family, don't wait if you don't have to. For single women, there is always the option of getting a sperm donor and doing it on your own. Just be realistic about doing this in a timely manner. And if you really want to experience the joys of childbearing, and using your eggs is no longer a viable option, you can always consider egg donation, up until the age of 50. Egg donation is an effective option for women over age 40 who have diminished ovarian reserve and mitigates the risk for chromosomal abnormalities in the offspring of an older mother. Egg donation has a high rate of success, regardless of your FSH level.

One more piece of advice, for you couples who have recently started trying to get pregnant: please relax! Many times, women will come in with a laundry list of what to do and what not do and questions of how to get pregnant. While there are some definite no-no's to keep in mind while trying to get pregnant, such as not consuming alcohol, smoking, using drugs, taking Advil and perhaps eating sushi, the truth is that the biggest deterrent to getting pregnant is stress. Having said that, there is evidence to show that heavy caffeine consumption, being overweight or underweight, or even over-exercising can negatively affect fertility. After making reasonable lifestyle modifications, the next advice is to relax and not be so nervous about the process. If you are young and have been trying for less than a year, the only thing you should be doing on day 12 through 14 is having a great dinner and a nice after-dinner reunion with your partner. Throw out the ovulation kit, relax and enjoy your partner. For younger couples who haven't conceived after a year of trying, then it is appropriate to obtain a fertility consult. Likewise, for couples over age 35, six months of trying without conceiving should result in a fertility consult.

This may seem like somewhat of an anxiety-provoking litany of facts on fertility, but it's not meant to be. This article is simply meant to give you the facts on your biological timeline when it concerns fertility. Being armed with the facts will help you make smart decisions regarding your fertility and life. For those wonderful women who have worked hard on their careers or on other pressing matters that have resulted in delaying reproduction, you are not alone and it's normal to feel the anxiety and sometimes depression associated with this subject. Luckily, you do have options, knowledge and lots of support.

Rachel Oosterbaan, MD, is an internal medicine attending at Northwestern Memorial Hospital and a clinical instructor at the Feinberg School of Medicine.