Can I Take Creatine While Pregnant?

I’m really into weight training, and just started trying to get pregnant. I’ve been taking creatine as part of my regimen but wonder if it’s safe to take while trying to conceive. What about when I get pregnant? I’ve heard mixed messaging — some people stop taking it right away, and others say that it is actually beneficial for the baby. What does the data say?

—“Working out” the answers

Creatine is a compound made of three amino acids, which you need for muscle functioning. People generally get creatine through food like meat and fish, but creatine supplements provide a much higher dose. The basic idea is that having more creatine helps build more muscle, which can help with athletic performance.

I could write a whole article on creatine, but the bottom line is that there is a lot of evidence that it can help in building muscle when combined with weight training. At the typically used doses, it is considered very safe.

When it comes to pregnancy and breastfeeding, the rhetoric is the usual “This hasn’t been proven safe, so avoid it.” In the case of pregnancy, however, that may be counterproductive. It is possible that creatine supplementation in pregnancy could be beneficial.

The evidence for this comes from theory and from data on mice. On the theory side, researchers have speculated that because pregnancy requires more energy, extra creatine could be beneficial. This is supported by a body of evidence from mice that shows that taking creatine in pregnancy improves newborn outcomes. Most notably, it protects against the impacts of brain hypoxia (when the brain is deprived of oxygen during birth). Brain hypoxia can also happen with humans, and is a source of birth injury with long-term consequences. Based on the mouse evidence, researchers have suggested that creatine supplementation might be a generally effective intervention in pregnancy. Some go so far as to suggest that creatine supplementation might be especially important in pregnancy.

Obviously, people are not mice, and more needs to be done to show that this might have an effect in people. But animal models are an excellent starting point.

On the flip side: there is no reason to think creatine supplementation during pregnancy would pose a danger, based on either the mice evidence or our understanding of biology. However, there are no randomized trials showing safety either. Clearly there is work to be done evaluating both the possible benefits and the safety profile here.

For you, making this decision without better data, it’s a familiarly complex position. It’s tempting to say, “Ask your doctor” — always a fine idea, but they have no more data on this than I do. In the end, you have to make this decision under some uncertainty.

Independent of what you decide in pregnancy, the situation in breastfeeding has similar uncertainty. We know that creatine passes through breast milk. It is possible that with very high levels, infant kidneys would struggle to process it. It is therefore often recommended that you abstain from supplementation through the first six months (after six months, kidneys are better developed). This is, again, based largely on theory, not data.

Finally: what about while trying to conceive? Even if you plan to quit supplementing during pregnancy, there does not seem to be a strong reason to stop during the period of trying to conceive. The impacts of supplementation are short-term, and there is no reason to think it would impact the chance of conception.