Joan Lunden did it at 52, Jane Seymour at 44, Annette Bening at 41, and Desperate Housewife Marcia Cross at 44. Nope, we're not talking botox or tummy tuck, we're talking kids-childbirth that is. But while technology is making mad leaps and bounds to keep up with these older moms, what's often missing from celeb stories is that many times these women have fertility help.

While celeb stories and their babies convey it's never too late or you're never too old, reality skews differently. "The biological clock is not a myth--it's very real and it ticks for both men and women, but for women it ticks louder and earlier," says Serena Chen, M.D., reproductive endocrinologist and director of the division of reproductive medicine at the Institute of Reproductive Medicine and Science at St. Barnabas in Livingston, New Jersey.

"Nature just didn't have that in mind for us, and her plans are very different from what we're doing in modern society." This whole strategy of women going to college and having a career and then finally settling down and having kids in their 40s or beyond is not really the way we were designed biologically. "In some ways it's more normal to be infertile at age 40 or above, than it is to be fertile," Chen says. The thing we worry about is the ovaries; that's the part that seems to age.

Cara Birrittieri, author of "What Every Woman Should Know about Fertility and Her Biological Clock," says if women walk into a clinic at 45 or 50, they might be able to have babies but they're not likely going to be using their own eggs.

"So even if you're really healthy and you eat right and exercise and do all the right things," adds Chen, "that doesn't mean you'll necessarily be fertile."

Besides fame and cash, do celebs possess superhuman fertility? Not likely. Studies show that just 0.2 percent of women over 50 can produce viable eggs, for instance. Birrittieri warns older moms not to be misled by celeb stories. Enjoy their happy pregnancy and childbirth news, but at the same time be mindful of your own biological clock waning.

Boarding the Baby Bandwagon
If you are just getting started at 40 or beyond, it's a good idea to have a thorough check up, and take vitamins and folic acid before attempting to conceive to lower the risk of neural tube defects. Women at high risk because of a medical problem, irregular periods, smoking, those who are significantly overweight and/or have a history of pelvic infections may not be as healthy from a reproductive standpoint as they should be, and must check with a reproductive endocrinologist early on in their process.

"One thing I think we should warn people about over 40 is that Clomid or the "fertility pill" is really over used. And for women over 40 who have a period every month, Clomid is a total waste of time; it can actually lower your fertility," says Chen.

Clomid is a drug that is easy to take, it's cheap, every gyn is familiar with it--and a lot of people have friends who got pregnant on clomid, but the problem is that it's really not helpful for older women. Chen says it tends to work best for women under 32. However, there are other injectable fertility medications that a specialist can prescribe.

The next step for fertility is generally invitro fertilization. With IVF, a woman uses her own eggs and injectable fertility drugs. The eggs are taken out of the body through a small needle in the vagina during a procedure under anesthesia, and are then mixed with sperm in a dish where they make embryos. The best embryos are selected to put back in the uterus. "This can be very helpful because a lot of age-related infertility is a numbers game," explains Chen. Since many of the eggs are not good, many may not fertilize, and the embryos may not be viable. This process allows good embryos for selection. That's part of the success. Also attributing to it: more than one embryo is implanted, so if one doesn't take another might.

Chen further explains that St. Barnabas is using PGD (preimplantation genetic diagnosis), which is a helpful tool for older IVF patients. It weeds out some genetic problems within the embryos and does an even better job of selecting healthy ones. A big part of age-related infertility is chromosomal abnormalities in the embryos from the eggs, so genetic testing allows the weeding out of these chromosomally abnormal embryos, like those with Down syndrome, and helps select the more normal ones. "It's a new technology and it can't test for everything but it can be very helpful in older women," says Chen.

Other options for older moms-to-be have seen less success. About 100 children have been born using frozen eggs. Success with frozen eggs or embryos is increasing, but it is still much lower compared to invitro fertilization with fresh eggs. In one recent study, 237 of 737 eggs survived after thawing. And Italian researchers achieved fertilization with 123 of the eggs, transferred embryos into 104 wombs, and succeeded with 15 pregnancies and 13 births.

Maintaining the pregnancy can be troublesome too, as first trimester miscarriage is more common in women over 40--likely because of those chromosomal abnormalities. Down syndrome and abnormal embryos are the most common cause of miscarriage--and those problems are more common in the over-40 woman. Perhaps not surprising, women over 50 are at increased risk for preeclampsia and gestational diabetes, and the majority will require a C- Section delivery, according to a 2002 study in "The Journal of the American Medical Association."

Yet, while it may seem doom and gloom, researchers are diligently at work enabling women in their 40s and 50s the opportunity for motherhood. Celebs do have an advantage over the rest of us aging commoners, and that is the cash for the best IVF programs and reproductive specialists. In vitro fertilization runs about $12,400 per cycle in the United States, according to the American Society for Reproductive Medicine. And it's not uncommon for women to require two or three tries before succeeding.

"The biggest thing for women over 40 is awareness. Awareness that fertility wanes at 40," says Chen. While knowing so might not change your life plan or career goals drastically, being aware of what you may face on the mommy trail after 40 could help you decide your next move.