Does Being Over 35 Put Your Pregnancy at Risk?

Medically Reviewed by Traci C. Johnson, MD on June 08, 2023
7 min read

Being an older mom can have some advantages. You may be more financially secure, and you may have more life experience to bring to the job of parenting. Most older moms have healthy pregnancies and deliver healthy babies. Still, your chances of developing certain problems are greater when you’re 35 years old or older.

Use that as a reason to take care of yourself. Keep every appointment with your doctor or midwife, who will want to monitor your pregnancy with extra care. They'll help you understand recommended tests and put your risks in perspective. Ask questions to stay informed. Being prepared can help you respond if there's a problem.

Remember, most moms 35 and older have healthy babies and normal pregnancies. The risks for you and your baby are a little higher than average, but still very low. Some of those risks include:

Birth defects. Older women are more likely to have a baby with a chromosome disorder such as Down syndrome. If you are age 25, the chance of Down syndrome is about 1 in 1,250. If you are age 35, the risk increases to 1 in 400. By age 45, it is 1 in 30.

Miscarriage. Most miscarriages happen in the first 13 weeks of pregnancy. With age, your risk of early miscarriage goes up. At age 35, the chance is about 20%. By age 45, your chance is 80%.

High blood pressure and diabetes. You may be more likely to develop high blood pressure or diabetes during pregnancy. These conditions can cause problems including miscarriage, growth problems in your baby, or complications during birth.

Placenta problems. Placenta previa happens when the placenta covers all or part of your cervix. This can lead to risky bleeding during delivery. If you’re in your 40s, you’re three times more likely to have placenta problems than a woman in their 20s. Even so, the problem is rare.

Premature birth and low birth weight: Older women are more likely to deliver their babies prematurely, before 37 weeks. As a result, older moms are at risk of having babies weighing less than 5.5 pounds at birth.

Although these risks are real, you can control many of them with good prenatal care. Through prenatal screening and testing you can know if your baby has a problem -- or a higher chance of one -- before birth. The information is extremely helpful to your doctor to help plan best management during pregnancy, labor and delivery.  With that information, you can get ready to care for a child with disabilities if necessary.

You can't do much to change your genes. But genetic screening and testing are available so that you can learn if your babies have a problem before birth. Your doctor may suggest you speak with a genetic counselor beforehand. If you have any questions or concerns, be sure to bring them up before having any tests.

Pregnant women get lots of routine prenatal tests including blood tests, including blood sugar tests (also called glucose monitoring), and ultrasounds.

Screening tests are different. They're optional, low-risk tests that don't diagnose anything. Instead, they give you a sense of your baby's chance of having certain conditions. While helpful in many cases, these tests can produce some false positives. That means the test says your baby has a problem when they really don’t. This can cause a lot of unnecessary stress.

While screening tests are recommended for all women, whether you get them is up to you. Your doctor or midwife may suggest you speak with a genetic counselor before you make any decisions. If you have any questions or concerns, be sure to bring them up before having any tests.

Screening tests include:

Nuchal translucency screening. During your first trimester, your doctor or midwife may do a special type of ultrasound to check the thickness of your baby's neck along with blood tests to look for certain things that may be linked to birth defects. The combined results can tell if your baby has a higher risk of having Down syndrome, trisomy 18, and other chromosome disorders.

Quad marker screen. During the second trimester, your doctor or midwife can do this blood test. It helps show your baby's risk of Down syndrome or other chromosome problems and neural tube defects, such as spina bifida and anencephaly.

If your tests come back normal, you may decide to stop there and trust that your baby doesn't have a neural tube defect or genetic disorder. Remember, a bad result doesn't mean your baby has a birth defect. It means your baby may have a higher risk. You may want to follow up with further testing to learn more, including:

  • Amniocentesis (amnio): During an amnio, a very thin needle goes into your belly to withdraw a small sample of amniotic fluid and cells for study in a lab. Amnio can spot many birth defects. This is generally done after 16 weeks.
  • Chorionic villus sampling (CVS): During CVS, a small sample of cells is taken from the placenta and tested for genetic disorders. This is generally done earlier in the pregnancy than an amnio.

You may also be offered cell-free DNA testing.

Keep in mind that these tests are not risk-free. Before having any, talk to your doctor about the risks and benefits and what is the best choice for you.

Women over age 35 may skip screening tests and go directly to prenatal diagnostic testing.

If results from screening tests raise concerns, or if you want further reassurance that your baby does not have certain problems, your doctor or midwife may suggest these diagnostic tests. Unlike screening tests, these tests are accurate ways of diagnosing problems. However, they do have some risks, including a slightly higher rate of miscarriage. You need to weigh the pros and cons.

Amniocentesis (called amnio for short). During an amnio, the doctor guides a very thin needle into your uterus and takes a small sample of amniotic fluid and cells to test. Amnio can spot chromosomal problems such as Down syndrome and trisomy 18. You usually have this test after 16 weeks.

Chorionic villus sampling (often called CVS). During CVS, your doctor takes a small sample of cells from the placenta to test for genetic disorders. This is generally done earlier in the pregnancy than an amnio.

Cordocentesis (also called fetal blood sampling). If the results of the amnio or CVS are unclear, your doctor may take a sample of blood from a vein in the umbilical cord to check for problems in your baby.

Pregnancy puts extra demands on your body. When you’re older, these demands may increase even more. To maintain your health and the health of your baby, take extra special care of yourself no matter how old you are.

  • Preconception counseling
  • Get early and regular prenatal care.
  • Take prenatal vitamins every day that contain 0.4 milligrams of folic acid, which can help prevent certain birth defects. Start at least 2 months prior to conception.
  • Eat a healthy, well-balanced diet that includes a variety of foods. An average-weight woman needs to add only 300 calories a day during pregnancy. That's about a cup of low-fat yogurt, a medium apple, and 10 almonds.
  • Maintain a healthy weight during your pregnancy by gaining the recommended amount of weight. These guidelines are based on whether you’re at a healthy weight, underweight, or overweight before you become pregnant. Of course, these are estimates. Check with your doctor about how much weight you should gain.

Weight status before pregnancy

Recommended range of weight to gain

Underweight

28-40 pounds

Healthy weight

25-35 pounds

Overweight

15-25 pounds

Obese

11-20 pounds

Your weight status before pregnancy is based on your weight and height. Your doctor can help you determine yours.

  • Exercise regularly. Discuss your routine with your doctor or midwife.
  • Minimize stress. Cut back on activities you don't need to do and ask for help when you need it. Talk with a friend or your spouse or partner about what stresses you out. Practice relaxation techniques like meditation or breathing exercises.
  • Make sure you get enough shut-eye. Your body is going through many changes as your baby grows, so you need your rest. Aim for about 7 to 9 hours of sleep a night.
  • Don’t smoke, and avoid secondhand smoke. It's bad for you and your baby. If you've tried to quit but can't, talk with your doctor or midwife about getting help. The sooner you quit, the healthier it is for your baby. But quitting at any time during your baby’s development will still make a difference.
  • Take only the over-the-counter and prescription medicines that your doctor or midwife has OK’d for you. Don’t take any herbal or natural remedies without checking with your doctor or midwife.
  • If you use illicit drugs or can't stop drinking alcohol, talk with your doctor or midwife about where to get help specifically for pregnant women. The sooner you ask for help, the better off you and your baby will be.