Trying to conceive a baby can be stressful or fun—depending on your circumstances. But preparing for pregnancy should involve more than just the biological logistics of joining egg with sperm. It also means making sure that you are as healthy as you can be so that your baby is, too.

“If you have medical problems, get those under control,” says Catherine Spong, M.D., deputy director of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. “Entering pregnancy healthy gives you the best possible chance to stay that way yourself and have a healthy baby.”

And if you aren’t preparing for pregnancy in the near future? There’s no downside to optimizing your health. Plus almost half of all pregnancies are unplanned, so it only makes sense for women who are sexually active to consider their reproductive health.

A two-year collaborative effort by experts from government agencies, national medical organizations, and nonprofits such as the March of Dimes yielded recommendations for healthcare providers and consumers to improve preconception health and care. Here are the top five:

1. Take Folic Acid

This nutrient is essential for the development of a fetus’ spinal cord and nervous system development. Aim for 400 micrograms per day starting at least three months before becoming pregnant to cut the risk of neural tube defects by at least half.

2. Stop Bad Habits

That means using illegal drugs, smoking, and drinking alcohol excessively. It’s never safe to smoke or use recreational drugs during pregnancy because those substances can harm the developing fetus even before you realize you are pregnant. And as soon as you know you're pregnant, or if you are actively trying to become pregnant, give up alcohol entirely: Any alcohol during pregnancy—especially during the first trimester—puts your baby at risk for fetal alcohol spectrum disorders, according to recent research.

3. Control Chronic Disease

If you have a medical condition such as asthma, diabetes, epilepsy, or high blood pressure, be sure to get it under control. For example, losing excess weight before pregnancy decreases the risk of neural tube defects, preterm delivery, gestational diabetes, blood clots, and other adverse effects.

Also be sure that your vaccinations are up to date. Rubella (German measles) and chickenpox can cause birth defects and complications if you get them while pregnant. But if you haven’t received these two vaccines before pregnancy, do not get them while pregnant because they are live vaccines and are not recommended during pregnancy.

4. Watch for Harmful Drugs and Supplements

Talk with your doctor and pharmacist about any over-the-counter and prescription medicine you are taking, including vitamins and other dietary or herbal supplements. Some medication, such as the acne drug isotretinoin (Accutane), can cause miscarriages and birth defects and shouldn’t be taken by women who are—or might become—pregnant. For other medication, your doctor may prescribe a lower dosage or an alternative drug.

For more information see our articles about the "Health Risks of Drugs During Pregnancy" and "10 OTC Drugs to Avoid During Pregnancy"

5. Get Moving

It’s much easier to maintain regular physical activity if you establish the habit before you become pregnant. It can be difficult or sometimes not recommended to start a new exercise routine after you become pregnant, but physical activity during pregnancy is important. “You should remain active and not be sedentary during your pregnancy,” says Michelle L. Drew, M.P.H., C.N.M., a nurse midwife at Christiana Care Health System’s Department of Obstetrics and Gynecology in Newark, Del. Regular exercise can also somewhat help manage weight gain, and obesity increases the likelihood of a cesarean.