Pregnancy Guide for Moms-to-Be of Advanced Maternal Age
January 5, 2018
Finding out that you’re expecting is always exciting—and a little nerve-wracking—no matter how old you are. But when you’re of advanced maternal age, you do have more to think about when it comes to keeping you and baby healthy throughout your pregnancy.
“Advanced Maternal Age (AMA) is the term for the general reality that the risks of having trouble conceiving a healthy pregnancy, as well as carrying a healthy pregnancy, are increased in ‘older’ women,” says Joshua U. Klein, MD, FACOG, chief medical officer at Extend Fertility, a New York City-based egg freezing service. Of course, problems don’t suddenly set in the moment you turn a certain age—rather, the likelihood of complications grows incrementally as women get older, he explains. “But because most risks start increasing meaningfully in the mid-30s, a common age cut-off for AMA is age 35.”
Unfortunately, those risks can present themselves at every stage of the pregnancy experience, from conception to childbirth. But just because you’re in your mid-thirties or older doesn’t mean you’ll encounter complications. Either way, it helps to be informed. Here, we break down the possible risks women of advanced maternal age may face during each leg of the journey, and what you need to know to have the healthiest pregnancy possible.
When you’re of advanced maternal age and thinking about starting a family, the key to a healthy pregnancy is preparing before you even conceive. “If a woman is thinking of getting pregnant and is over the age of 35, and particularly if she has underlying health issues, it’s prudent to seek medical counseling prior to getting pregnant to optimize her health,” says Kecia Gaither, MD, MPH, FACOG, a maternal fetal medicine specialist and director of perinatal services at NYC Health +Hospitals/ Lincoln. “This step is very important, not only for her, but also for her developing baby, as many diseases seen in older women have a direct impact on her developing baby.”
During preconception counseling—with either an ob-gyn or a reproductive endocrinologist who can assess your state of health—your doctor can advise you on healthy lifestyle changes, from adjusting your diet and workout routines to kicking bad habits like smoking. She can also run tests to ensure there aren’t any undiagnosed health conditions, such as hypertension or diabetes, and to check for warning signs that you may be at high risk for certain pregnancy complications. “Many factors are modifiable or preventable, and the advantage of preconception testing and counseling should be emphasized,” says Scott Roseff, MD, FACOG, a fertility specialist with IVFMD, a Florida-based fertility clinic.
Generally speaking, the majority of women successfully conceive after three months, but it will likely take longer for women of advanced maternal age to get pregnant. “Fertility in women starts to decline at age 32 and becomes a sharper decline by age 37,” says Brian Levine, MD, practice director at the fertility clinic CCRM New York. “The definition of infertility is trying to achieve pregnancy for six months or more when you’re over 35 years old, or one year if you’re under 35. Any timeframe outside of that window should be a red flag and a signal to see a doctor and be evaluated.” At that point, you may want to discuss possible fertility treatments, from oral medications to injectables and in-vitro fertilization (IVF).
Many people assume women over 35 commonly get pregnant with twins thanks to IVF treatments, but the surprising truth is that your likelihood of naturally conceiving multiples increases with age. “As a result of the ovarian reserve starting to decrease, the body starts signaling the ovaries to release more eggs, so mothers closer to the age of 40 have a higher chance of conceiving multiples naturally,” explains Adeeb Khalifeh, MD, a maternal fetal medicine specialist at Einstein Medical Center Philadelphia. In fact, you’re three times more likely to get pregnant with fraternal twins between the ages of 35 and 40 than between the ages of 20 and 25.
As your age increases, so do the general health risks to you and baby during pregnancy. “You could be 35 or 36 and have a completely healthy pregnancy—but the risk of complications starts increasing,” Khalifeh says.
Once any underlying health conditions have been diagnosed and addressed, Gaither suggests seeing a doctor who specializes in high-risk pregnancies so you and baby are properly monitored throughout your journey.
The risk of genetic abnormalities in baby is higher in women of advanced maternal age. “Women don’t make new eggs as they age, so the older eggs have chromosomes that are more apt to make mistakes, resulting in higher odds of genetic abnormalities in their babies,” Roseff says. Whereas women at age 25 have about a 1 in 1,064 chance of having a baby with Down Syndrome at week 10 of pregnancy, the likelihood at age 35 increases to 1 in 240 and at 45 to 1 in 19.
Now with the availability of non-invasive prenatal testing (NIPT), you can have blood drawn in your first trimester to determine whether baby has chromosomal abnormalities such as Down Syndrome, trisomy 13 and 18. But while NIPT tests can reveal whether there’s a high probability that your child has an abnormality, they’re screens, not diagnostic tests. To determine whether baby in fact has one of these conditions, you can opt for amniocentesis or CVS—however, these invasive tests come with risks, so talk to your doctor to find out if they’re right for you.
Moms-to-be of advanced maternal age are also more likely to develop gestational diabetes, which can cause baby to be larger than normal, as well as certain birth defects, such as abnormal spine development and heart disease. According to Khalifeh, the risk of gestational diabetes is about 5 to 6 percent for a woman between 30 to 40 years old, 10 percent for women 40 to 45, and 15 to 20 percent for women over 45. “It’s a continuum—the further along in age you are, the higher the risk of diabetes,” Khalifeh says. This is also true for hypertension and preeclampsia.
Moms of all ages come in all shapes and sizes—but women of advanced maternal age are statistically more likely to be overweight than younger mothers-to-be, Roseff says. The American College of Obstetricians and Gynecologists recommends that women with a “normal” body mass index of 18 to 25 aim for a pregnancy weight gain of 25 to 35 pounds. Obesity during pregnancy can further increase the risk of certain conditions, such as gestational diabetes, hypertension, cardiovascular problems and babies with high birth weights. One of the most effective ways to protect yourself and your baby is to be at a healthy weight when you first conceive.
Age can play a role even in the last stages of pregnancy as you prepare for baby’s arrival, including when you may go into labor and how baby may be delivered.
The risk of giving birth prematurely is higher in women of advanced maternal age, since they’re more likely to have pregnancy complications that require an early delivery, such as preeclampsia. “With increasing age, the odds of her placenta properly and adequately nourishing her baby may decrease due to poorer blood flow through her uterus,” Roseff says. In fact, a large scale Swedish study found that, compared with women ages 20 to 24, women 35 to 39 had a 70 percent increased risk of very preterm birth (before 32 weeks), and a 20 percent increased risk for preterm birth before 37 weeks. Among women 40 and older, there was a 90 percent increased risk of very preterm birth and a 50 percent increased risk for preterm birth.
Additionally, older moms are more likely to need a c-section. “The reasons for higher risk of c-sections likely include increased medical complications, labor dysfunction, as well as an overall lower threshold for cesarean delivery given the expectation of fewer future pregnancies in AMA patients,” Klein explains. In a recent study, the cesarean delivery rate was 20 percent for women ages 25 to 34 years, 26 percent for women 35 to 39 years, 31 percent for women 40 to 44 years, 36 percent for women 45 to 49 years, and 61 percent for women over 50.
However, it’s important to remember that all women age differently, so the risks vary from person to person. Just because you’re of a certain age doesn’t mean you’re certain to have a tougher pregnancy. As Gaither says, “In general, if a woman over the age of 35 is in good health, has no underlying conditions and has had a normal genetic screening, her age in and of itself doesn’t pose a significant risk for having a healthy baby and a normal vaginal delivery.”
Published January 2018