If you’re pregnant or are trying to conceive, you’ve heard by now how important nutrition is to meet the needs of your developing baby and maintain your own strength. After all, you are growing a human being! A healthy diet is crucial, and during pregnancy, you need certain nutrients in greater amounts. Your doctor will likely recommend a prenatal vitamin as the best way to ensure you are meeting the particular dietary requirements of this special time.

Still, the myriad choices of prenatal vitamins can be overwhelming: prescription or non-prescription, chewable or pill, tablet or capsule. Not all vitamins contain the same amounts or combinations of nutrients. Most vitamins will have a similar list of nutrients, but there are important differences to look for, including more or less of a particular vitamin or mineral. So read the labels closely to make an informed decision based on your diet and medical history. Fear not if you are one of the many women that experiences nausea from their prenatal vitamins — you can always experiment to find the option that works best for you.

To help guide you down the daunting prenatal vitamin aisle, here’s a cheat sheet of the most important nutrients you need during pregnancy.

Iron: All prenatal vitamins will contain iron. Iron is especially important in pregnancy to make all that extra blood, which will grow new vessels, the placenta, and the umbilical cord that nourishes your baby. When you add in that your baby is making his own blood, you can see why many women develop anemia (low levels of iron in the blood) during pregnancy. Prenatal vitamins usually contain 30-90mg of iron. Those with higher amounts may contain a gentle laxative, like docusate sodium, since iron can cause constipation. Iron may be partly responsible for nausea associated with vitamins, so you may wish to start with a lower iron vitamin if you do not have a history of anemia. If you start to feel sluggish and low energy, you can try a brand with more iron.

Folic acid: Folic Acid is the most absorbable form of folate, and all prenatal vitamins will contain at least 400 mcg, which is the recommended daily dose for all women of childbearing age. Folic acid is important for preventing very early abnormalities in the baby’s brain and spinal cord (neural tube defects) — many recommend taking a vitamin with folic acid before you even conceive. If you have had a baby with a neural tube defect, your doctor may advise you to take up to 4mg (4,000 mcg) of folic acid daily. Many prenatal vitamins contain 1mg or more. Taking large doses is not a big concern as your body can get rid of extra. However, it can mask a vitamin B12 deficiency, so very high doses of folic acid should be accompanied by B12 supplementation.

Iodine: You won’t see iodine listed on every prenatal vitamin label, but it’s a crucial component of a good prenatal vitamin and here’s why. Iodine supports good thyroid function, which is necessary for a healthy pregnancy and baby. Severe iodine deficiency in a pregnant woman, although uncommon in the U.S., can cause extensive cognitive and physical impairments in her baby. Seafood, dairy products and iodized salt are the most common dietary sources of iodine, and if you’re not eating these regularly — or, like me, you have a family history of hypothyroidism — supplementing is a good bet. The American Thyroid Association recommends supplementing with 150 mcg of iodine (in the form of potassium iodide) daily during pregnancy and breastfeeding. Most of the vitamins on the market that do contain iodine have this amount.

Calcium and Vitamin D: These two nutrients are important for the healthy development of a baby’s bones, teeth, nerves, heart and muscles. Calcium is a building block of teeth and bones, and is also involved in nerve and muscle function. Vitamin D is necessary to absorb calcium from the foods that you eat. The Academy of Nutrition and Dietetics recommends 1,000mg of calcium per day before, during and after pregnancy. A standard prenatal vitamin usually contains 200-300mg, so be sure to make up the difference through diet, or talk to your doctor if you think you are not meeting this requirement. He or she may suggest an additional calcium supplement. Look for a vitamin that contains at least 400 IU of vitamin D (cholecalciferol, or D3, is the most absorbable form). If you’ve received a diagnosis of vitamin D deficiency, the American College of Obstetrics and Gynecology recommends 1,000-2,000 IU per day of vitamin D as a safe upper limit.

Omega-3 Fats: You probably know about the health benefits of omega-3 fats, and in pregnancy, these essential fats are important for your baby’s brain and eye development. Fatty fish like salmon are the best dietary sources, but walnuts, flax seeds and pumpkin seeds contain good amounts of the essential omega-3 fatty acid alpha-linolenic acid. Many prenatal vitamins now include omega-3 fats, like DHA and EPA (the kind found in fish), usually as a separate liquid capsule. If you can afford the extra expense, it’s good insurance against an imperfect diet (and who has a perfect one?).

Helpful Hint: Once you’re taking your prenatal vitamin regularly, make sure you are not getting supplemental doses of vitamins from other sources like drinks and energy bars. Some vitamins can be toxic to your baby if taken in high doses, especially vitamin A in its retinol form. Any extra vitamin A should always be in the form of beta carotene, which is converted to active vitamin A in your body when it’s needed, and therefore not toxic. When it comes to vitamins and minerals, getting enough is important, but more is usually not better.

Image source.