Synopsis
Book by Kittel Mary Metzger Deborah
Extrait
Healthy Women Are Fertile Women Degrees. Meaningful work. Adventure. A soul mate. Expense accounts. A good breast pump. We are women of the 21st century, and we want it all. Why shouldn't we? Our foremothers shook the foundations of science, politics, and cultural traditions to obtain the electrifying array of options we now embrace. Life expectancy for women has increased by 30 years over the last century--so we have more time to fill the political offices, executive boards, Olympic team positions, religious leadership roles, and military posts that are now our brass rings to claim. Furthermore, "the widespread availability of contraception that first became available to the baby boomer generation empowers us to choose when and if we want to become a mother," observes women's studies scholar Sara Evans, Ph.D., Distinguished McKnight University Professor in the department of history at the University of Minnesota in Minneapolis, and author of Tidal Wave: How Women Changed America at Century's End. As our vision of what constitutes a full life broadens, so does our to-do list. According to the U.S. Census Bureau, more women are waiting longer before they get married. We are spending more time being educated before plunging into the work world. For a growing population of women, childbearing also comes later in the sequence of life events. Twenty-five years ago, only 5 percent of U.S. women had their first child at the age of 30 or older. By the year 2000, one out of four births were to first-time moms in their thirties or beyond. "Divorce and remarriage and the evolving concept of family are also important motivations for later childbearing," Dr. Evans points out. People may have already had children when they were younger but may strongly wish to have children in new partnerships. The growing number of over-30 mothers also includes single women who have decided not to wait any longer for a lifelong mate, as well as lesbian mothers who are taking advantage of the advances in sperm donation and fertility drugs. Twice as many women ages 35 to 39 gave birth in 2000 compared to 1978, while the number of births to women ages 40 to 44 more than doubled over the past 2 decades. But as commonplace as it has become, giving birth at the age of 35 or older is actually considered "delayed" or "older" childbearing in the medical books. That's not because 35+ women aren't zesty or have necessarily reached even half of their life expectancy, but because statistically they've moved out of the peak period of fertility when conceiving comes quicker and high-risk pregnancies are less common. "No doctor will disagree that biologically, the early twenties are the optimal time to conceive. But situationally, the best time may be much later for today's woman," points out Vanessa Cullins, M.D., vice president of medical affairs at Planned Parenthood Federation of America in New York City. "Throughout the world, we see a pattern where as a country gets more technically advanced, women tend to delay childbearing as they increase their education and employment status in the interest of providing the best for their children. That's what happened in the United States, and it's also starting to happen in developing countries like Bangladesh and Nepal," says Dr. Cullins. In addition to the women's revolution and the technological boom weighing in on the age of childbearing, it's become downright fashionable to be a mature mom. Our superstars are looking more capable and beautiful than ever with a baby in tow, including Geena Davis (first-time mom at age 46), Madonna (second-time mom at 41), Kim Basinger (gave birth at 44), and Susan Sarandon (who had babies at 39, 42, and 45). Former cover girls now focused on their baby girls (and boys) include over-40 moms Christie Brinkley, Iman, and Cheryl Tiegs (mother of twins at 52 who used a surrogate to carry the babies, although the eggs were her own). Going by the pages of the fashion or news magazines, our cultural icons are making later-age pregnancy look glamorous. Even easy. In truth, delayed childbearing challenges us to become increasingly careful about the choices we make, particularly the ones regarding how well we take care of ourselves over the years. "If you expect to conceive at a later age, it's all the more motivation to be aggressive about preventing premature aging, chronic medical conditions, and reproductive health threats," says reproductive endocrinologist and gynecologic surgeon Deborah Metzger, M.D., Ph.D., medical director of Helena Women's Health in San Jose, California, and medical advisor to this book. How Long Can You Stay Fertile? In 2001, the American Society for Reproductive Medicine (ASRM) launched a public service campaign to get the word out about threats to fertility. As part of the campaign, the slightly disconcerting image of a baby bottle in the shape of an hourglass was posted on buses in major U.S. cities and distributed in flyers to college students across the country. Underneath, a slogan read: "Advancing Age Decreases Your Ability to Have Children." The campaign is both sobering and encouraging. The first take-home message about age and fertility is that reproduction does not come with a contract for unlimited hours. Eventually all women go through menopause, which means you've had your final menstrual period and thus your last chance to naturally ovulate an egg that could become your genetic offspring, says Michael Soules, M.D., professor of obstetrics and gynecology at the University of Washington in Seattle, who is leading the ASRM infertility prevention campaign and is an expert on reproductive aging. Before the curtain closes entirely, fertility becomes gradually less reliable in the 10 years leading up to menopause (known as premenopause, or sometimes loosely referred to as perimenopause--the time "around" menopause). RESOLVE: The National Infertility Association aptly describes premenopausal fertility as "decreased, but not entirely absent." But how much a woman's fertility is affected in the transitional period going into menopause is highly individualized. It's not uncommon for women only in their mid- to late thirties to take fertility drugs because their cycles have already begun to fizzle. Other women conceive through their early and middle forties with ease--including Cherie Blair, the wife of the British prime minister, who had her fourth child at the age of 46 (when she wasn't even trying). There are also unusual cases of women who managed to achieve natural conception even later, such as a California grandmother of 13 who made national news in 2002 after giving birth to triplets, which she reportedly conceived naturally at the age of 54. "If you make a chart of age-related fertility, it would not have a straight line of decline," explains reproductive epidemiologist Shanna H. Swan, Ph.D., research professor in the department of family and community medicine at the University of Missouri-Columbia. It starts out lower since menstrual cycles aren't reliable in early puberty, goes up to its max in late adolescence, and declines slightly throughout the late twenties and early thirties. That decline starts to go down steeply around age 35, says Dr. Swan. The next largest, and sharpest, decline comes around the age of 45 for most women, according to the U.S. Census Bureau, as women are within just about 6 years of the average age of menopause, about 51. To put it into perspective, experts often cite the odds that for women in their forties, the chance of conceiving in any one cycle is about half of what it was in their twenties. "I counsel women who don't plan to conceive until around age 40 that they are taking the chance of not having fertilizable oocytes (eggs). Chronological age is not the only predictor of fertility, but it must be considered," says Wanda Ronner, M.D., a gynecologist at Pennsylvania Hospital of the University of Pennsylvania Health System in Philadelphia and coauthor of The Empty Cradle: Infertility in America from Colonial Times to the Present. Fortunately, there are other variables, and we can control them a whole lot more than when we might get our first hot flash. "Actions people take long before they may be ready to have children can impact their ability to eventually conceive," the ASRM campaign says. "In many cases, it's not necessarily age itself that is compromising fertility in older women as much as that by the time women are 35 or over, they have simply had more opportunities to develop conditions that cause infertility," Dr. Metzger explains. "Just like diseases such as lung cancer or HIV/AIDS, infertility can often be prevented," the ASRM campaign states. Reducing Your Risks In the following pages, the top fertility experts in the world--including the scientists who run the most cutting-edge research labs, the doctors who head the world's leading fertility programs, mind-body visionaries, and preeminent health care practitioners--share their specific insights into what can either compromise or optimize fertility over time. Together, their expert guidelines offer protection for each major facet of fertility: the eggs and sperm themselves, the sexual organs, the hormones, your overall health, and your psyche. One of the clearest risks to the reproductive organs are sexually transmitted diseases (STDs), which can block a woman's fallopian tubes, toughen up her uterus with scar tissue, or bring on the devastation of cervical cancer. They also contribute to cancer and tubal disorders in men. You will be coached throughout this book to practice prevention of and early intervention for STDs. The same baby bottle that was portrayed as an hourglass is also pictured in the ASRM campaign as an ashtray, with the message: "If you smoke, this might be your only use for a baby's bottle." The hard-hitting slogan is targeted to both genders, since sperm and egg quality is profoundly threatened by cigarette smoke as well as other substance abuses. In fact, a woman can lose so many eggs by smoking that it can speed up her passage into menopause by 3 years. Experts also emphasize that anyone who wants to conceive should make every effort to avoid secondhand smoke, which contains more than 60 carcinogens that can threaten reproductive health. (For more information about the fertility-robbing effects of smoking, see chapter 4.) The ubiquitous ASRM baby bottle is also squeezed with measuring tape to relate that "12 percent of all infertility cases are a result of either weighing too much or too little." Weight, fitness, and nutrition play major roles in the maintenance of reproductive hormones. Chapter 5 is devoted to helping you achieve your best fertility weight, while chapter 16 offers a complete hormone-balancing strategy. And because a mighty immune system is necessary to prevent hormone disorders, structural problems, and high-risk pregnancies, plenty of guidelines will be included on a diet and lifestyle that keep the immune system in top form. While basic good health is the backbone of reproductive health, there are other fertility-protective steps. When going about their day-to-day business, women need to be conscious of the fact that they are carrying precious cargo in their ovaries, experts caution. Certain chromosomal abnormalities responsible for the greater number of birth defects and miscarriages in later-age pregnancies are often simply blamed on "old eggs." But they can actually be the result of cumulative exposure to radiation or mutation-causing chemicals, RESOLVE reports. Chapter 14 offers specific advice on reducing your day-to-day exposure to various forms of radiation, while chapter 9 will teach you to reduce environmental toxins that you probably didn't even realize were there. "You do not have to give up all of life's little indulgences in order to conceive and carry a healthy baby, but you do have to moderate," states M. Kelly Shanahan, M.D., chair of the obstetrics and gynecology department at Barton Memorial Hospital in South Lake Tahoe, California; director of the Emerald Bay Center for Women's Health in South Lake Tahoe; and author of Your Over-35 Week-by-Week Pregnancy Guide. Rather than overemphasizing your chronological age, this book supports the position that the best marker for how fertile you are and how fertile you will be in the future depends largely on how well you've managed your risk factors over the years. The concept of "preconception care"--which usually refers to health modifications recommended to a couple just as they are trying for a family--has been expanded to include all the years leading up to conception. "With a longer-term focus, you won't get to conception time and have months of work to do, or worse, find out that you (or your partner) developed a fertility problem years ago," explains Dr. Metzger. High-Tech to the Rescue? Around the same time that contraception became widely available in the 1960s, so did fertility drugs. Giving eggs an added push to mature and ovulate, these drugs can often restore or improve fertility in a woman whose own hormone regulation system is dysfunctional. In 1981, the first baby was born through in vitro fertilization, the first of the assisted reproductive technologies (ARTs) to introduce sperm and egg outside the body and guide the implantation process. By 1987, these procedures could also be performed with donor eggs, and 10 years later, the use of frozen embryos also became possible (sperm preservation had already been around since the 1970s). Today, scientists are rapidly developing the technology to freeze eggs and pieces of ovaries, advances that should be routinely available in the next 5 years. Each time one of these new technologies is introduced, a flood of publicity surrounds it, and hopeful couples rush to infertility clinics looking for a miracle. Among those who seek treatment are inevitably healthy and very fertile women in their thirties who panic, prematurely, because they have heard so much about "the infertility problem." "I call these women pre- infertile," says Dr. Ronner. Infertility rates for all ages have actually remained relatively stable over the past 3 decades, but the increasing availability of infertility services has created a misperception of an infertility epidemic, according to the Centers for Disease Control and Prevention. Dr. Ronner counsels her "pre-infertile" patients--who tend to be thirtysomething professional women eager to do everything the right way-- that it's normal for them to expect a year of unprotected intercourse before conceiving. "When it comes to women in their forties and their late thirties, it's reasonable to expect even longer than a year to get pregnant. However, women over 35 are encouraged to be evaluated and possibly go into treatment before a year is up, because our interventions work better when you're younger. So you have to weigh the two," says Steven Sondheimer, M.D., professor of obstetrics and gynecology at the University of Pennsylvania Medical Center in Philadelphia and a spokesperson for the Association of Reproductive Health Professionals.
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