An international survey of 17,500 women released last year by the AFA found that most respondents mistakenly thought their fertility began to decline at age 40. The countries surveyed included the United States, England, Sweden, Uganda, Germany, Israel, the Netherlands, Argentina and Turkey.

While it's true that fertility takes a nosedive at 40, the decline actually begins in a woman's late 20s and accelerates throughout her 30s at a rate of 3 percent to 5 percent per year. By age 40, a woman has just a 5 percent chance of getting pregnant naturally in any given month.

Even women who should know better, sometimes don’t — or maybe they're in denial, thinking they'll be the one to beat the odds. Dr. Richard Scott, director of reproductive endocrinology at the University of Medicine and Dentistry of New Jersey, says he recently saw a 45-year-old woman with a graduate degree in biology who said she wanted to get pregnant with her own eggs. But chances of that happening are slim.

While it’s true that, thanks to fertility treatments, many women get pregnant today who wouldn’t have a decade ago, Scott says, there still is a lot of misunderstanding about just what medicine can do to fight back the hands of time when it comes to baby-making.

“Clearly there’s a big gap out there,” he says.

Can't stop the clock
Dr. Richard Paulson, chief of reproductive medicine and infertility at the University of Southern California in Los Angeles, sees the same thing. “I think there’s still a huge level of ignorance about the biological clock,” he says.

Doctors can cheat time a bit by coaxing reluctant egg and sperm together, he says, but they can’t force aging, deteriorating eggs to miraculously make babies — and there's no indication science will make that happen any time soon.

“Our ability to reverse that is no more likely than our ability to reverse aging,” he says, but that point often is lost on women who feel they’re a specimen of health and wonder why they can't get pregnant.

It’s true that measures such as maintaining a healthy weight, avoiding sexually transmitted diseases and not smoking all can help prevent fertility problems, notes Dr. Sandra Carson, a professor of obstetrics and gynecology at Brown University and director of reproductive medicine and infertility at Women and Infants Hospital of Rhode Island in Providence.

But being healthy isn’t enough to override the biological clock. Fit women in their mid to late 30s can be “incredulous” that they can’t get pregnant, Carson says. “Just because you’re healthy doesn’t necessarily mean that you’ll be fertile.”

Carson was involved with a campaign launched by the American Society for Reproductive Medicine in 2001 that aimed to educate women about the age-related decline in fertility. But that campaign didn’t sit well with a lot of women who felt that doctors, many of them older men, were trying to tell young women that they should trade in their careers for the mommy track — and stay home barefoot and pregnant.

Carson believes the campaign did help some to raise awareness about a woman’s biological clock but that many couples today still aren’t deciding to start their families sooner.

“I’m concerned that it just makes women worry more and not really change their decisions,” she says.

Couples in their late 20s and early 30s often are still career-focused and they may be waiting to buy a car or a house. Or, like Steve Houghtaling of Kalispell, Mont., they just want to enjoy some more child-free years.

"I became a father at age 39 only because I was having too much fun," he says.

It also was important, though, for Houghtaling, now 54, who works as a quality assurance specialist at a call center, to be able to provide well for his family. "I did want to better myself to be able to offer a good life for not only my wife but my children," he says. "I didn't want to scrape by like my parents did."

As was the case with Houghtaling, priorities with men and women who delay having children often shift to starting a family by the time they're in their late 30s, but by then it may be too late for some.

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