If you’ve endured the heartbreak of a miscarriage—and roughly 15 percent of known pregnancies do end in miscarriage—you may have also experienced an unpleasant side effect of the experience: a crushing sense of guilt. Did the pregnancy end because of the cocktail you had before you knew you were expecting? Or the piece of raw-milk cheese you mistakenly ate a few weeks ago?

The truth is, most early miscarriages are caused by genetic abnormalities that are far beyond the control of a mom-to-be. “In most cases, there’s nothing you can do to cause a miscarriage, and nothing you can do to prevent it,” says Siobhan Dolan, M.D., a medical advisor to the March of Dimes and an attending physician in the Division of Reproductive Genetics at Montefiore Medical Center, the University Hospital for Einstein, in New York City. “It’s a very challenging condition. We’d love to have a treatment we can offer, but there are very few effective interventions.”

  • Healthy Pregnancy Nutrition Tips

That said, a healthy lifestyle before and during pregnancy may help, says Erika Nichelson, D.O., a board-certified ob-gyn at the Family Childbirth and Children’s Center at Mercy Medical Center in Baltimore. Here are her recommendations:

  • If you’re not already pregnant, schedule a pre-conception visit with your gynecologist. She’ll review your medical history, ask about your lifestyle, perform an annual exam (if you’re due for one), and take blood samples to check for blood type, Rh factor, and varicella (chicken pox) and rubella immunity. If you haven’t been vaccinated against these infectious diseases, now’s the time to get your shots. Though skipping them won’t increase your odds of a miscarriage, the vaccines are live viruses and can’t be given once you’re pregnant.
  • Eat a well-balanced diet. You may already be taking a prenatal vitamin, but don’t think of it as a magic bullet. A well-balanced, healthy diet is the best way to get the vitamins and nutrients your body needs to nourish your baby, says Dr. Nichelson. Plus, studies have found that loading up on a variety of fresh fruits and veggies every day can significantly lower your odds of having a miscarriage.
  • Exercise in moderation. You should continue your usual exercise routine once you’re pregnant, though now’s not the time to start training for your first marathon. The key is moderation: Some research indicates that seven hours or more of high-impact exercise a week while pregnant could greatly increase your risk of miscarriage. Contact sports are also off the table for now, as they could lead to an injury or fall.
  • Limit caffeine. Some doctors suggest moms-to-be restrict their intake to no more than 200 milligrams a day, or roughly two 6-ounce cups of coffee, tea, or other caffeinated beverage. But to be on the safe side, ask your ob-gyn what she recommends.
  • Avoid drugs, smoking, and alcohol.
  • Get a handle on stress. Besides improving your overall mood, staying relaxed may also help the health of your pregnancy. In one study, women who said they felt happy, relaxed, and in control were 60 percent less likely to have a miscarriage.
  • Get your blood sugar under control (if you have diabetes). According to Dr. Nichelson, elevated blood sugar can lead to fetal malformation and a subsequent loss.
  • Ask if you should take low-dose aspirin. Although a recent National Institutes of Health study found that, in general, low-dose aspirin did not appear to prevent miscarriage in women with one or two prior pregnancy losses, it did appear to be effective for a smaller subset of women, and Dr. Nichelson believes it works.
  • Vet any meds you’re taking with your doctor. If you’re taking medication (even an over-the-counter remedy), always run it past your ob-gyn first to make sure it’s safe for your baby. ACE inhibitors (heart medications), for example, can cause fetal malformations and increase your odds of a miscarriage. If possible, avoid all medicines while you’re pregnant. “That’s the safest way to go,” Dr. Nichelson says.