Interview has been edited for clarity.
What is considered advanced maternal age?
According to Dr. DeTata, 35 is the starting point for advanced maternal age.
“For many reasons, people delay having a baby to an older age, and this is becoming more popular. Celebrity stories in the media can make it seem common and easy to have a baby after 35 or even many years later. Advances in infertility treatments and the ability to save eggs and embryos make it easier to get pregnant after 40.”
She says that despite developments and improvements in the ability to take care of older pregnant people, the risks of advanced maternal age still exist and it becomes even riskier as age increases. Multiple pregnancies, which can be common after infertility treatments, also increase the risks.
Risks of advanced maternal age
Risks for the pregnant person
Dr. DeTata says that with age, people are more likely to have chronic diseases such as high blood pressure, diabetes, and thyroid disease. Even when the person is healthy prior to pregnancy, the physical stress of pregnancy can make pregnancy problems more common.
According to Dr. DeTata, people over the age of 35 have an increased risk of the following:
- Ectopic pregnancy
- Miscarriage
- Hypertension of pregnancy and preeclampsia
- Anemia
- Preterm labor
- Hypertension
- Gestational diabetes
- Thyroid disease
- Placental problems
- Prolonged labor
- Delivery problems
- Postpartum hemorrhage
- Blood clots and stroke
- Pulmonary embolism
- Cardiac problems, such as myocardial infarction and cardiomyopathy
She says that while the overall risk of death during labor at any age is very low, advanced maternal age increases this risk.
Risk for the fetus
“There is an increased risk of genetic problems due to aging of the eggs,” says Dr. DeTata. “While the male body continuously makes sperm, the female body is born with all the eggs it will ever have, so the age of the eggs increases over time.”
Embryos from older eggs have an increased risk of genetic problems, particularly chromosomal problems, as they develop. For example, the risk of Down syndrome, a chromosomal problem, is 1 in 1,480 at age 20; 1 in 353 at age 35; and 1 in 35 at age 45. Prenatal screening and diagnostic testing is done differently depending on age.
Dr. DeTata says that older people are more likely to have poor blood circulation to their placenta, which can lead to poor fetal growth, low fluid, spontaneous preterm delivery, and stillbirth.
They’re also at an increased risk for illnesses that can affect the growth of their baby, such as preeclampsia or gestational diabetes.
It’s also possible that risks associated with advanced maternal age may make it necessary to have an early delivery, so the risk of having a premature baby is also increased.
How to prepare for pregnancy at an advanced maternal age
Dr. DeTata suggests getting to the healthiest weight possible, exercising, eating a healthy diet, and minimizing stress.
“See your doctor for a checkup. They can run tests for diabetes, thyroid disease, and hypertension. It’s best to test for these diseases before getting pregnant, as they may be present without any symptoms. Be sure to tell your doctor that you are trying to get pregnant, so that any medicines they give you to treat problems are medicines that are safe for your baby.”
She also advises making sure that you’re immune to diseases that can affect a growing baby, such as varicella and rubella. While some vaccines can be given safely during pregnancy, the vaccines for varicella and rubella should not be given to pregnant people. It’s best to check your immunity before trying to conceive so that you can get these vaccines before becoming pregnant.
You can also perform genetic testing to learn if you or your partner are carriers of certain genetic diseases. Even if the carrier testing is negative, your baby might still be at risk of genetic problems due to age.
How does advanced maternal age affect labor and delivery?
As a pregnant person nears their due date, the placenta starts to degenerate, Dr. DeTata explains. This means that the blood vessels age, and the circulation through the placenta to the baby can decrease. With a degenerating placenta, the fetus may not receive the nutrition and oxygen it needs to grow well and remain healthy.
This happens earlier in people who are over 35. Because of this accelerated aging of the placenta, doctors often recommend inducing labor for delivery at 39 weeks.
Dr. DeTata says that older people have an increased likelihood of needing a cesarean delivery because their uterine contractions may not be strong enough. This also means it’s more likely that labor will be prolonged.
“With an aging placenta, the fetus may have some decreased circulation that becomes noticeable with the added stress of labor. Babies of older parents are more likely to have abnormal heart rate tracings that make delivery by cesarean safer than vaginal delivery,” Dr. DeTata says.
“But advanced maternal age doesn’t have an effect on breastfeeding. In fact, older parents may be even more likely to breastfeed longer than their younger counterparts.”
What are the pros of waiting until you’re older to have a baby?
Dr. DeTata says that while there are a number of physiological risks associated with advanced pregnancy age, getting pregnant when you’re older also has a few advantages. For instance, older parents tend to be more secure in their careers, may be in better financial shape, and often have more resources to help care for and raise a child.
People who have children early in their careers have more difficulty advancing due to time away to have their baby.
Dr. DeTata says that it’s important to see a doctor before deciding to get pregnant and that having good prenatal care helps reduce risks and makes a safe and healthy pregnancy more likely.
Summing up
According to Dr. DeTata, the age at which someone has a baby is not often a conscious choice. Rather, it’s dictated by life circumstances.
She recommends that all people consider whether or not to have a baby and make a reproductive life plan. If you want to get pregnant, it’s good to discuss your pregnancy plans every year when you see your health care provider for a checkup.
History of updates
Current version (15 November 2021)
Medically reviewed by Dr. Cynthia DeTata, Clinical assistant professor of obstetrics and gynecology, Lucile Packard Children's Hospital, California, US