Is creatine safe during pregnancy?

What does the evidence say about creatine during pregnancy?

1. A 2025 review of creatine safety concludes the supplement should not be recommended during pregnancy outside of research studies, since evidence in humans remains considerably limited even though animal research is reassuring. 1
2. In a 2025 guinea pig model of a full-term pregnancy, daily creatine supplementation didn't change gestational weight gain, fetal growth, birth weight, pregnancy length, or stillbirth rates compared with unsupplemented pregnancies. 2
3. Researchers have proposed that creatine could support the fetus by maintaining cellular energy production and reducing oxidative stress in tissues like the placenta and fetal brain, but this review states long-term use of creatine in human pregnancy has not been fully evaluated and urges caution before recommending it. 3
4. Creatine occurs naturally in human breastmilk at an average of about 10.5 mg per liter, and a federal drug-and-lactation reference advises avoiding creatine supplements postpartum unless a healthcare professional has prescribed them, since extra creatine can raise a breastfed infant's serum creatinine in a way that complicates kidney-function readings. 4
5. Outside of pregnancy, creatine monohydrate is considered safe at typical doses of 5 to 20 grams a day in the general population, including in some clinical groups, though people with existing kidney conditions are advised to have kidney function monitored with tests that aren't thrown off by creatine intake. 1

Is creatine safe in each trimester?

• First trimester. If you were already taking creatine for exercise or cognitive support before conceiving, there isn't yet a human safety study to confirm whether continuing through the first trimester is fine. Flag it at your first prenatal visit so your provider has the full picture.
• Second trimester. The placenta and the fetal brain have high, fluctuating energy needs, which is the theoretical reason some researchers are studying creatine in pregnancy. That rationale currently comes from animal and lab research, not from human pregnancy trials.
• Third trimester. A 2025 guinea pig study modeling a full-term pregnancy found creatine supplementation didn't change birth weight, pregnancy length, or newborn outcomes, but animal data doesn't automatically transfer to people. Keep your provider updated if you're still taking it close to delivery.