What should you look for in a prenatal (or antenatal—the two words mean the same thing) vitamin? Research shows that they can reduce your baby’s risk of birth defects and support their healthy growth and development. They can also decrease your risk of preterm delivery, preeclampsia, and other complications. Research further suggests that most women do not get adequate pregnancy nutrition from food alone. However, vitamins are typically regulated for food safety and hygiene standards only, not for efficacy, and there are significant variations between what prenatal vitamins contain and the claims made on the packaging. So what’s the best vitamin to take?

The prenatal vitamin you’re happy to keep taking.

Vitamins can cause constipation, bloating, nausea, and digestive discomfort at a time when you may already be dealing with pregnancy sickness. Therefore, the best supplement for you may be the one you can tolerate, as you are more likely to continue taking it.

The prenatal vitamin with enough folic acid (at least 400 mcg).

Folic acid (Vitamin B9) is proven to prevent neural tube defects, early brain and spine development, and your baby’s growth in general. It can be found in peanuts, orange juice, beans, and dark green, leafy vegetables. It’s difficult to get enough food to support your pregnancy. Folic acid is often described as the queen of prenatal vitamins. Ideally, you will take it at least three months before conceiving and throughout the first trimester, as it is less important after this period. Some women (e.g., epileptics) need more than the standard 400 mcg. The combination of a folic acid supplement and fortified foods can decrease your baby’s risk of developing neural tube defects by up to 90 percent.

What about methylated folate vs. folic acid?

Methylated folate and folic acid are not the same. There is more established evidence for folic acid, and while methylated folate is often touted as more bioavailable and potentially easier to digest for some women, as an evidence-based resource, unii.com recommends you stick to taking as much folic acid as your doctor recommends.

The prenatal vitamin with vitamin B12 (especially if you are vegan or vegetarian).

This B vitamin helps to prevent anaemia in pregnancy and supports your baby’s cognitive development. You need 2.6 mcg in pregnancy.

The prenatal vitamin is vitamin B6.

You need 1.9 mg a day in pregnancy and can get it from starchy vegetables, whole grains, sunflower seeds, and red meat.

The prenatal vitamin with vitamin D.

This is especially important for women who live in dark climates and is important for your baby’s skin and brain development. You need 15 mcg a day in pregnancy.

The prenatal vitamin with Vitamin A.

Vitamin A is important for eye development and bone growth; ideally, you’d get 770 mcg in pregnancy. You can have toxic levels of Vitamin A that are associated with birth defects, and though the upper limit of consumption is very high (3000 mcg per day), you should still speak to your doctor before taking this.

The prenatal vitamin is choline.

Choline is important for your baby’s brain development. You can get it from eggs, fatty fish, red meat, and chicken. You should get at least 450 mg a day.

The prenatal vitamin is iodine.

We get iron from regular table salt, but some women need to supplement. You need 220 mcg in pregnancy.

The prenatal vitamin with calcium.

The one with calcium is important for your baby’s bones and teeth. It also keeps mum from losing calcium stores in her own bones and teeth, which can lead to osteoporosis and dental problems in later life. Calcium can be found in dairy products, small fish (e.g., sardines), and dark green, leafy vegetables. ACOG recommends 1,000 mg daily for pregnant women.

The prenatal vitamin with iron (at least from the second trimester).

Iron is super-important in pregnancy to support your expanding blood volume in pregnancy, especially in the second and third trimesters, and it is quite common for moms to need to supplement their antenatal diet, even if they eat plenty of red meat. You need about 27 mg of iron every day in pregnancy, though seek your doctor’s guidance if you are vegan, vegetarian, or have a history of low blood iron. You should also speak to your doctor if your iron supplement causes you gastrointestinal trouble, as they may be able to suggest alternatives or safely adjust your dose.

The prenatal vitamin with DHA.

You should have 2-300 mg a day for your baby’s brain and skin. Look for non-fish liver-based supplements.

Does the form of the prenatal vitamin matter—liposomal, liquid, pill, gummy, or capsule?

Yes, the form matters. Not all forms can accommodate a range of minerals, vitamins, etc. in the recommended daily amounts. Gummies cannot accommodate iron all, so you may need to take a separate iron supplement. Liposomal supplements can be easier to digest than capsules or pills, but can be less convenient to take every day, and pills and capsules can be hard to swallow and digest, so it’s all relative to what you need and what you tolerate best.

For more advice on taking care of yourself in pregnancy, labour, and birth, check out Unii’s Antenatal Classes, with prenatal video episodes taught by senior NHS midwives, an award-winning obstetrician and gynaecologist, and six other leading healthcare experts. Only at unii.com.

Antenatal Class Questions: How can I choose the best prenatal vitamin?