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35 and Pregnant

Planning for Baby after age 35? Age and Pregnancy Matter

One in five American women now have their first baby after the age of 35. Most have healthy pregnancies and babies. If you are planning to have a baby after age 35 or are pregnant, there are some important considerations to take into account. While you may not feel any different than you did in your twenties – age-related changes in your body can affect fertility and pregnancy. Being aware of them and taking steps to have a healthy pregnancy are important to you and your baby's well-being.

How Does Age Affect Fertility?

As women enter their thirties, their fertility naturally declines. While you may not have noticed any change in your menstrual cycle, your body is undergoing changes:

  • A decrease in ovulation – releasing an egg that can be fertilized
  • Change in the health and number of eggs – you are born with all the eggs you'll ever have, in your thirties and beyond you have fewer eggs
  • Eggs become more difficult to fertilize
  • Higher rates of having multiples

Other age-related changes involve your partner's age as well:

  • Decrease in sperm counts in men in their late thirties and older
  • Decrease in sperm quality and mobility

And overall with age, we often experience:

  • Decrease in frequency of intercourse
  • Presence of other medical and gynecological problems such as high blood pressure, diabetes, endometriosis which can affect pregnancy

These effects on fertility can make it take longer to conceive and women in their mid-thirties are more likely to experience fertility problems. If you have been trying for six months without result, it's time to talk to your physician.

35 & Pregnant - Risks & Health Concerns

While most women over 35 do have healthy pregnancies, the occurrence of infertility and pregnancy complications is higher than for younger women. With advances in medicine and prenatal care though, you can increase your chance of having a safe and healthy pregnancy. Some of the risks associated with age and pregnancy over 35 include:

  • Increased risk for birth defects and chromosomal abnormalities, such as Down's syndrome. Women in their twenties experience a 1 in 1,400 chance, while at age 35 it is 1 in 400 and at age 40 the rate is 1 in 100.
  • Increased miscarriage rates. Women in their twenties experience a 12 -15% rate, while women at age 40 experience a 35% rate. Part of this increase is due to the higher rate of chromosomal abnormalities – a common cause of miscarriage.
  • Pre-existing health problems can also affect your fertility and pregnancy.

Women over 35 are also more likely to experience complications that arise during pregnancy:

  • Gestational diabetes. This develops during pregnancy and can lead to having very large babies at risk for injury during delivery and newborn health problems. Women over 35 are twice as likely to develop gestational diabetes.
  • High blood pressure. Pregnancy-induced high blood pressure can lead to preeclampsia, a dangerous and potentially life-threatening condition that requires immediate attention.
  • Placental problems. Women over 35 are twice as likely to have placenta previa – a condition where the placenta covers part or all of the cervix. This condition can lead to severe bleeding during delivery. This may lead to cesarean birth.
  • Premature birth and low-birth weight babies.
  • Stillbirths. Women over age 40 are two to three times more likely than women in their twenties to have a stillborn baby (when the fetus dies after 20 weeks of pregnancy.)
  • Cesarean births. Mothers over 40 are twice as likely to have a c-section.

Steps to Take

If you are planning to conceive after age 35, the first step to take is to make a pre-conception appointment with your OB/GYN physician. It's important to be as healthy as you can and to address any existing health concerns as well as discuss the type of prenatal care you will require.

You may also talk with a genetic counselor to learn more about associated risks and discuss any concerns you may have.

If you are already pregnant, becoming aware of the risks and health concerns associated with over 35 pregnancies is also important. Your physician can discuss any age and pregnancy issues that may affect your baby and your health, as well as various screenings and tests that can help assure you that your baby is developing normally.

Screening for Aneuploidy/Down Syndrome

Aneuploidy refers to abnormal chromosome development – which causes birth defects such as Down syndrome. You will be offered special screening tests and diagnostic tests due to the higher incidence of birth defects. It's important to note the difference between screening and diagnosing.

Screening Tests

  • First Trimester Screen
  • Second Trimester (Quad) Screen

These are blood tests on the mother offered in the first and second trimesters. They can indicate if your baby is at an increased risk for having a chromosomal or other birth defect. These tests do NOT tell you if your baby actually has a birth defect or chromosomal abnormality such as Down syndrome. If the results are normal, these tests can help reassure you. They are not 100% accurate though and cannot rule out with certainty that a fetus does not have a chromosomal problem. Typically, if the results are abnormal, your physician will recommend doing a diagnostic test to confirm or rule out abnormalities.

Diagnostic Tests

  • Chorionic Villus Sampling (CVS) – offered after 9 weeks of pregnancy
  • Genetic Amniocentesis – offered between 15 – 20 weeks of pregnancy

Because these tests involve taking blood or tissue samples from the placenta or amniotic sac, they have a slight risk of fetal loss. These tests can confirm or rule out the presence of chromosomal abnormalities. A genetic counselor can help you learn more about birth defects and the risks and long-term outlook for various conditions.