It’s important to start taking prenatal vitamins as soon as you think you may want to get pregnant. In fact, doctors want you on these vitamins two to three months before you even start trying to conceive. That's because, by taking prenatals before you get pregnant,  you'll be sure to get the appropriate amount of those essential vitamins and nutrients, like folic acid and iron,  that contribute to your baby's growth and development. But is there ever a situation when it’s too soon to take prenatal vitamins? Is it safe? Are there any added benefits? Here's what OB/GYNs want you to know. 

How are prenatal vitamins different from regular vitamins?

Although they may have some similarities, prenatal vitamins and standard multivitamins are not the same. Prenatal vitamins are specifically formulated with the crucial nutrients needed to support your health during pregnancy, and your baby's health and development. 

“Prenatal vitamins contain higher amounts of calcium and vitamin D to support bone and tooth development in utero,” explains Anate Brauer, M.D., OB/GYN and reproductive endocrinologist in New York. “They also contain higher doses of folic acid than standard vitamins, which support neural tube development as well as DHA, which supports neural development in a fetus.” 

Should you take prenatal vitamins even when you aren't trying to conceive or pregnant? 

No, it's not a good idea to take prenatals if you aren't pregnant, trying to conceive (TTC) or thinking about TTC.  

Prenatal vitamins may have a similar formulation to a standard multivitamin. However, prenatal vitamins contain additional nutritional support including calcium, vitamin D, iron, folic acid and DHA needed for fetal neural development. So if you’re not pregnant or TTC, Dr. Brauer says these additional nutrients are not necessary. What’s more, she notes that taking excessive vitamin amounts can lead to side effects such as constipation and nausea. 

Instead, a woman’s multivitamin is typically sufficient when you're not pregnant or TTC, she adds. Finding a multivitamin specific to your age and gender can also be helpful. For example, women who are older may need more calcium for their bone health as they age, so finding a supplement that has extra amounts of calcium would be a good choice. 

There are some rumors that prenatal vitamins can help with hair and nail growth. While this may be anecdotally true for some people who are otherwise deficient in some nutrients that prenatal vitamins have, Dr. Brauer says there is really no evidence that supports these claims. For these specific benefits, stick to supplements like biotin and vitamins B, C and A instead.