If you’re trying to start a family or hope to have more children, and you’re approaching (or passed) the big 4-0, you’re bound to have heard at least once that it’s a lot more risky to have a baby when you’re the other side of 40.

Actually, you’ve probably heard it many, many times. It pushes your stress and anxiety levels sky high, but is there any real truth to it? And if so, just how much risk are you facing if you get pregnant after the “big 40 deadline”?

Many IVF clinics won’t treat women over the age of 50, because the risks are simply too high. The Ethics Committee of the American Society for Reproductive Medicine advises doctors against IVF for women over age 50. But if you’re aged between 40 and 50, and you’re eager to have a family, how safe is it to do so? No one can give you a definitive answer, but here are the main risks to consider.

• Pregnancy conditions like preeclampsia, gestational diabetes, and placenta praevia
• Harm to your baby, like low birth weight and chromosomal defects
• Miscarriage and stillbirth
• Difficulties giving birth that could require interventions
• Having a multiple pregnancy (twins or triplets)
• Ongoing health issues like obesity

First of all, your background health makes a huge difference to the risks you and your baby could face. If you’re healthy, have no chronic conditions like high blood pressure, and conceived naturally, there’s no reason why your pregnancy should be higher risk than if you were a decade younger. Women who have some background health issues and conceived with the help of IVF could have a very different experience.

Does your age increase your risks of developing certain pregnancy conditions?

The older you are, the higher your risks of developing certain common complications of pregnancy, including preeclampsia, gestational diabetes, and placenta previa.

Preeclampsia

Preeclampsia is a serious pregnancy condition that is caused by high blood pressure. It can cause permanent organ damage and is potentially fatal for both the mother and the fetus. The only way to treat it is to deliver your baby, but that poses its own dangers for a baby that hasn’t yet reached full term.

Blood pressure (hypertension) generally rises with age, and many women have borderline hypertension without being aware of it.

Being pregnant puts a huge strain on your heart, far more than even strenuous exercise. At the same time, your body produces more of the reproductive hormone progesterone, which raises your blood pressure and cholesterol. If your blood pressure is already borderline or high, or you have heart issues, this can be enough to push you into preeclampsia.

If you’re aged 40+, your risk of developing preeclampsia jumps from 1.5% to 4.6%. However, if you’re otherwise healthy and your blood pressure is good or low, your age only slightly increases your chances of developing preeclampsia.

Gestational diabetes

Gestational diabetes is a form of diabetes that only affects pregnant women. Although you can develop it at any age, even when you eat a healthy diet, you’re four times more likely to experience it when you’re over 40 than when you’re in your 20s or early 30s.

Placenta praevia

During pregnancy, your uterus has to expand massively to accommodate the fetus, which requires a healthy and effective blood (vascular) system. The older you are, the greater your risk of vascular disease, which affects major organs like the uterus, as well as your heart.

If your vascular system isn’t operating at full power, you might develop placenta praevia, which is when the placenta doesn’t move up and away from the opening of the uterus. As it tries to expand, it can rupture, causing severe bleeding and bringing on premature labor.

Women over 40 have a seriously increased risk of placenta praevia, compared with women under 30.

Could your baby be harmed if you’re over 40?

Anything that affects your health, as the gestating mother, can also affect the health of your unborn child. Preeclampsia, gestational diabetes, and placenta praevia can all bring on preterm labor, which could harm your baby.

Studies have also found that if you’re giving birth for the first time at age 40 or over, the baby’s birth weight is likely to be significantly lower.

Overall, one study found that babies born to mothers aged over 40 were 35% more likely to need to spend time in intensive care, and 70% more likely to be born with some medical anomaly.

Chromosomal defects

As you get older, your eggs get older too. That makes it harder for you to conceive, because there are fewer follicles left to develop into eggs, but it also affects the quality of the eggs that remain. Lower quality eggs are less likely to divide correctly during gestation, increasing the risk of chromosomal defects.

Down’s syndrome, or trisomy 21, is the best known and most common type of chromosomal defect. It happens when the 21st chromosome divides into three copies instead of just two, in every cell. When you’re aged 25, the risk of giving birth to a baby with Down’s syndrome is just 1 in 1,250, but that rises to 1 in 400 at age 35 and 1 in 100 at age 40. By the time you’re 42, you have a 1 in 60 chance of giving birth to a baby with Down’s syndrome, and a 1 in 12 chance at age 49.

Other less-common chromosomal defects include trisomy 13, or Patau’s syndrome, and the even rarer Edward’s syndrome or trisomy 18.

Are mothers aged 40+ more likely to experience miscarriage and stillbirth?

Older women are far more likely to suffer a miscarriage than younger women.

If you’re aged 30, the risk that your pregnancy will end in miscarriage is around 18%, but it rises to 38% if you’re 40, and almost doubles to 70% for women aged 45.

It’s not always clear why this happens. Chromosomal defects often trigger a miscarriage, and those are more common among mothers aged 40+. Another issue is that the older you are,

the more likely it is that you’ve developed a chronic condition such as high blood pressure, diabetes, or thyroid disease, which can complicate your pregnancy and increase the risk of pregnancy loss.

The risks of stillbirth also rise, especially once you pass your due date.

Up until 39 weeks of gestation, a 40-year old woman has a similar stillbirth rate to that of a woman in her 20s at 41 weeks. But once you pass week 39, your risks of stillbirth spike to double those of a woman aged 35. That’s why it’s better to induce labour in women aged 40+ once they reach their due date.

Am I more likely to have difficulty giving birth?

For a variety of reasons, women aged over 40 are more likely to experience complicated birth that requires interventions like forceps, vacuum, or a caesarean section. Some of the reasons include:

• You’re more likely to have a chronic medical conditions
• You’re at a higher risk of developing pregnancy complications like preeclampsia
• It’s more likely that your baby will be in breech position
• The uterine muscle becomes less effective as you get older, especially if this is your first birth

You’re approximately twice as likely to need a c-section if you’re over 40.

Although c-sections and assisted deliveries usually bring favorable birth outcomes, it’s worth remembering that it takes longer to recover from a c-section than from a vaginal birth, and that assisted deliveries like forceps increase your risk of tearing.

Are older women more likely to have a multiple pregnancy?

Oddly enough, yes. When you’re over 40, you’re naturally more likely to have a multiple pregnancy, although scientists aren’t sure why.

A multiple pregnancy can increase your risk of miscarriage. Multiple pregnancies are also more likely to be born with a low birth weight, which is associated with complications like cerebral palsy and learning difficulties, and 5% more likely to develop congenital anomalies.

In general, maternal mortality is 2.5 times higher for multiple births than when you give birth to a singleton baby.

Can I suffer ongoing health risks if I have a baby aged over 40?

There’s some evidence that women who have a baby aged over 40 are more likely to develop certain health complications after giving birth. If you’ve had gestational diabetes, you’re at higher risk of developing type 2 diabetes postpartum.

That said, although the higher risks of having a baby when you’re over 40 are real and serious, celebrating your 40th birthday isn’t in itself a reason to decide not to start or add to your family.

If you’re trying to get pregnant, either naturally or through IVF, it’s best to have a thorough screening first so that you’ll be prepared to deal with the impact of any health risks on your pregnancy and birth. And if you’re already pregnant, do take all the health checks and screenings recommended by your doctor. We wish that your pregnancy and birth experience is as smooth and healthy as possible.