Is there one? Here are the pros and cons of pregnancy in your 20s, 30s, and 40s.

americanbaby.com, August 2009

Is there a best time to have a baby? That's one of the questions for the ages. So much depends on who you are and where you are in your life when sperm meets egg. But whether you're in your 20s, 30s, or 40s, read on for some healthy advice, catered to you.

Terrific 20s

Let's Get Physical"_ In terms of the shape your body is in, your 20s are an ideal time to have a baby. If you receive good prenatal care, eat well, exercise, and maintain a healthy weight, you'll "have the best chance of a healthy pregnancy," says Rakhi Dimino, MD, an ob-gyn at the Woman's Hospital of Texas in Houston. "Your eggs are young so there's a lower risk for miscarriage and birth defects." You're also less likely to have the kinds of medical issues" high blood pressure, diabetes, and thyroid problems" that can crop up with age.

Timing Is Everything"_ Of course, other kinds of complications exist. Maybe you weren't exactly planning to be pregnant at this time. Natalie Martin, of Winter Garden, Florida, was 20 when she had her first child and 23 when she had her second. "My doctor always joked that I'm a baby machine because my body handled pregnancy so well," says the now 33-year old law school student. "But it was not the most pleasant experience because I was doing it on my own. Having children in your 20s when your life is not secure makes things much harder. My kids saw me cry one too many times for my liking." Still, if you're mentally and emotionally ready for it, the 20s can be a great time for a baby. Brooke Maroth, 29, had been married to her husband for three years when they started their family (when Maroth was 24). "I wanted to be a young mom so that when my children were grown and out of the house, my husband and I would still be young," she says. And having the energy to chase after a lively kindergartener and toddler, even in the second trimester, certainly doesn't hurt. "Compared to my older friends who've had babies, I feel like I have more energy," says Maroth, who manages to exercise regularly. Another plus: the 20- something body is amazingly resilient. " After having the babies," she says, "my body bounced back quickly."

Thrilling 30s

Let's Get Physical"_ Past a certain point, some women start to worry about waiting too long. "There's a switch that clicks on at 35: I want to get pregnant now!"says Jacques Moritz, MD, director of gynecology and the birthing center at St. Luke's Roosevelt Hospital in New York City. Yes, the risk that something could go wrong"with your health, the pregnancy, your baby"increases as you age, particularly once you're past your mid-30s. But before you freak out, remember: "It's a gradual increase. It doesn't suddenly jump way up at 35,"assures Dr. Dimino. Healthy habits can help roll back the reproductive clock. "A 39-year-old who's healthy, eats well, isn't obese, and doesn't smoke"her risks are going to be closer to the 30-year-old's,"says Mark Crider, MD, assistant director at Loch Haven Ob-Gyn, in Orlando, Florida. Even so, you might consider doing more genetic testing for Down syndrome and other chromosomal disorders that may occur when aging eggs don't split cleanly. Also be aware that your miscarriage risk increases as you age, and certain genetic tests, such as chorionic villus sampling (CVS) and amniocentesis, can add to this risk. While a woman in her 20s has a 10 percent risk of miscarrying, that number rises to 20 percent between 35 and 39, even without testing. "The first three months I was pregnant, I didn't really own the pregnancy,"confides Joanne Beer, a physician's assistant in Decatur, Georgia, who had suffered a miscarriage at seven weeks during a previous pregnancy. "I thought Let's not get too wedded to this. But after the three-month mark and after the amnio, it was amazing that it really seemed to be happening,"she says.

Timing Is Everything"_ Indeed, even with the precautions added, more women these days are having their first child in their 30s. One in five women has her first after age 35. Chances are, by your 30s, your career is in a good place, you're earning some decent money, and you're married or have a steady partner. You're ready to shift into the next phase of your life: starting a family. "I couldn't imagine being pregnant in my 20s,"says San Francisco travel writer Michele Bigley, 34. "My husband and I were doing a lot of growing ourselves. There wasn't any space for a child."Once they felt settled as a couple, space opened up, she says. Within a month of trying, Bigley was pregnant with her son, Kai, now almost 2. Keep in mind, though, that it's not always this easy. Even if you had no trouble getting pregnant in your 20s, fertility declines by about 30 percent in your 30s, so contact your doctor if you're over 30 and have been trying to get pregnant for six months or longer.

Fabulous 40s

Let's Get Physical"_ As much as we like to say that 40 is the new 30, the reality is that even if your body looks fabulous, it's still older and your eggs are too. And that means declining fertility and an even higher risk for miscarriage (up to 50 percent by age 44), stillbirth, and chromosomal disorders. A 35-year-old has an age-related risk for Down syndrome of 1 in 249. Skip ahead to age 40, and it's 1 in 68. So you might consider doing some more genetic testing to make sure everything is going as planned. Even when you're healthy, age can complicate things. "I take care of myself. I run. I eat really well. But I had a whole list of medical problems that I just didn't have with any other pregnancy,"says Doreen Wiggins, MD, an ob-gyn at Women and Infants Hospital in Providence, Rhode Island, who was pregnant with her fifth child at 44. She developed a thyroid condition and a blood clot in her lung. And her daughter showed up about six weeks early. "You don't realize how susceptible you are to the changes that come with time until you stress your body, and pregnancy can be a stress,"Dr. Wiggins says. "I emphasize health to my patients, but I'm not sure that even I understood what a difference 20 years can make."That also includes the way your body snaps back (or doesn't snap back). "I didn't gain much weight. I didn't get wrinkles or stretch marks, but my abdominal skin just won't go back the way it used to,"she says.

Timing Is Everything"_ A 40-something pregnancy can be a challenge, but it can also be a gift. "It wasn't like I chose to be in my 40s when I had my second child; it just happened that way,"says Joanne Beer, who had her son at 39 and her daughter at 42. "When I found out I was pregnant, it came as a really wonderful surprise,"she says. "Knowing what to expect the second time around, I was able to relax. I told myself, This will be the last time I'll be pregnant so let's enjoy the good parts of it."

Good Advice At Any Age

Here, the golden rules of any pregnancy

  • If you smoke, quit. Now. The potential complications are many: miscarriage, stillbirth, premature birth, and low birthweight. Babies born to smokers are also more likely to have heart defects, cleft lip/palates, asthma, and weight problems and to suffer from nicotine withdrawal. After birth, their risk for SIDS can triple.
  • Stick to Shirley Temples. Alcohol quickly crosses the placenta, and just a little bit will get your baby drunk, even if you're not even buzzed.
  • Kick the caffeine habit. It can increase your miscarriage risk and reduces blood flow to the baby. However, most experts agree that 200 mg or less (about one cup of coffee) per day is okay during pregnancy.
  • Get some exercise. Clear it with your ob-gyn first to make sure there's nothing that would stop you from working out. Once you have the green light, aim for 30 minutes of aerobic exercise on most days. It can keep your weight in check, help prevent gestational diabetes (or control it if you have it), build up stamina for labor and delivery, ease backaches and constipation, and help you sleep better.
  • Watch what you eat. You need only about 300 extra calories a day (and only 100 in your first trimester). The current guidelines suggest that women of normal weight gain 25 to 35 pounds during pregnancy, overweight women gain no more than 25, and obese women no more than 15. Excess weight ups the risk for gestational diabetes and pregnancy-related hypertension, which in turn boosts the odds of preterm birth, c-section, even stillbirth. Plus, babies born to heavy moms tend to have a greater risk for obesity and diabetes later on.

Testing for Down Syndrome

Two categories of tests

Screening tests

What they do Estimate the likelihood your baby will have DS

Examples Nuchal translucency ultrasound (measures the area behind the baby's neck, called the nuchal fold, and looks for the baby's nasal bone) and blood test, and quad screen (a form of blood test)

Diagnostic tests

What they do Tell you whether or not your baby has DS

Examples Chorionic villus sampling (a tiny sample of the placenta is extracted either by a needle through the abdomen or a slender catheter through the cervix into the uterus and tested for birth defects) and amniocentesis (in which a needle, inserted through the abdomen, extracts about an ounce of amniotic fluid)

Norine Dworkin-McDaniel had her son Fletcher, now 3, when she was 39. She writes the family life blog Don't Put Lizards in Your Ears at norinedworkin.com/blog.