Is NMN safe during pregnancy?

What does the evidence say about NMN during pregnancy?

1. In mice, a ten-day course of NMN given to obese females before mating improved egg quality without changing how many mice became pregnant or how large their litters were, and normalized the birth weight of pups born to mothers on a high-fat diet. 1
2. A separate mouse study gave NMN only to already-born adult offspring of obese mothers, not to the mothers during pregnancy, and found glucose tolerance improved within just 8 days while liver fat dropped by 23 to 50%. 2
3. Research comparing NMN with exercise as ways to reverse effects of maternal obesity also dosed the offspring after birth and weaning rather than dosing the pregnant mothers themselves, reinforcing that this line of research addresses reversing programming effects, not gestational exposure. 3
4. In a mouse model of type 1 diabetes, adding NMN directly to the lab dish culture medium during egg maturation, not giving it to a pregnant animal, improved the maturation rate and quality of the eggs. 4
5. The authors of the mouse offspring study explicitly note that human studies would still be needed before drawing conclusions, since their results describe dosing already-born mice, not any stage of pregnancy. 2

Is NMN safe in each trimester?

• First trimester. There's no first-trimester-specific research on NMN in humans or animals. Since this is also the stage when major organ development happens, this is exactly when stopping an unstudied supplement matters most.
• Second trimester. No new safety data emerges for the second trimester either. The rodent studies that used NMN around reproduction dosed it before conception, not during an ongoing pregnancy, so they don't tell us what happens with continued use partway through.
• Third trimester. Still no pregnancy-specific safety data by the third trimester. If you started NMN for a specific reason before finding out you were pregnant, this is a good point to confirm with your provider whether continuing makes sense before delivery.