You can't prevent a miscarriage, but there are ways to lower your risk

• To lower your risk of miscarriage, eat a healthy diet, exercise, and take prenatal vitamins.
• You can reduce miscarriage risk before becoming pregnant by limiting caffeine and managing weight.
• However, most miscarriages cannot be prevented and are often due to genetics.

Miscarriages are common, and nobody is immune. An estimated 10% to 20% of pregnancies end in miscarriage. But, some experts think that the percentage is probably even higher since some miscarriages occur before someone even knows they're pregnant.

"You can have a miscarriage as soon as you become pregnant," says UCLA OB-GYN Leena S. Nathan, MD. "Sometimes we see people who have a miscarriage very early on. We usually call that a chemical pregnancy because the pregnancy hormone hCG goes up, but we never actually see anything in the uterus."

How to lower your risk of miscarriage

While there is no foolproof way to prevent miscarriage, there are some lifestyle changes you can make before and during pregnancy to lower your risk.

Here's what you can do before getting pregnant to reduce your risk of miscarrying:

• If you've miscarried before: See your doctor to get tested to see what's going on. Some issues can be treated to make it more likely for an embryo to grow and continue full term. For example, looking for a blood clotting issue. "If we find something, then we can treat it with blood thinners in order to help with future successful pregnancy," Nathan says.
• Eat right and exercise: Nathan says, "Trying to be as healthy as possible before pregnancy can help prevent a miscarriage." Part of this includes quitting smoking before getting pregnant since smoking during pregnancy can increase your risk of miscarriage.
• Maintain a healthy weight: Diabetes and obesity can lead to other complications during pregnancy but they can also increase your risk of miscarriage. That's why Nathan recommends getting diabetes under control before pregnancy and losing weight, if necessary.
• Limit caffeine before conception: A 2016 study by the National Institutes of Health examined 344 pregnancies and found that the rate of miscarriage was higher if either one or both partners drank 2 or more caffeinated beverages in the weeks leading up to conception.

Here's what you can do during pregnancy to reduce your risk of miscarrying:

• Continue to eat right and exercise: Again, you want to live a healthy lifestyle for you and your baby. "Being at a healthy weight and having a healthy diet and exercise routine are really important for having a healthy pregnancy," Nathan says.
• Take prenatal vitamins: Folic acid, calcium, iron, and vitamin D will keep both you and the baby healthy. The healthier and more nourished you are during pregnancy, the better.
• Don't smoke and avoid secondhand smoke: A 2014 systematic review published in the American Journal of Epidemiology reported that each cigarette smoked per day increased the relative risk of miscarriage by 1 percent. The study also reports that secondhand smoke increased the risk of miscarriage by 11%.
• Don't use illicit drugs: The Cleveland Clinic says amphetamines, cocaine, marijuana can increase miscarriage risk.
• Don't drink: A 2019 study published in Alcoholism: Clinical and Experimental Research found that drinking alcohol during pregnancy increased the risk of a miscarriage by 19%.

You're most likely to miscarry in the first trimester

"It's most common to miscarry in the first trimester, which is up to 13 weeks," says Nathan. In fact, about 80% of miscarriages happen within the first trimester. After this, your chance of miscarrying drops.

However, you can miscarry as late as 20 weeks. Beyond that, if the pregnancy isn't successful it's no longer called a miscarriage, it's a stillbirth.

Insider's takeaway

There are plenty of reasons a miscarriage can happen, and unfortunately, some types of miscarriages simply can't be prevented.

"Most times [the cause is] something genetic, which is unpreventable, meaning there is something wrong with the chromosomes and either the egg or the sperm that came together," Nathan says.

"Other causes could be related to the mother's health. For instance, if the mother has a blood clotting issue, if the mother carries any sort of genetic mutations, health and lifestyle issues can cause miscarriages as well as smoking, diabetes, and obesity."

Then, there's always the possibility that you do everything "right" and still miscarry.

"When I see a patient who's had a miscarriage, I reassure them that it's nothing they did or didn't do because there's a lot of guilt that comes with having a miscarriage, but most of the time, it's unpreventable," says Nathan.