NMN During Pregnancy: Is It Safe? What Human Evidence Shows

NMN has not been established as safe during human pregnancy. Pregnant and breastfeeding people are generally excluded from NMN clinical trials, so the short-term safety data available in healthy adults cannot be transferred automatically to pregnancy.

Animal studies have reported effects on oocyte quality, fertility, ovarian aging, and embryo development, but those findings do not establish that taking an NMN supplement during human pregnancy is safe or beneficial.

For that reason, self-directed NMN supplementation during pregnancy is not advisable. If you are pregnant, trying to conceive, or breastfeeding, discuss NMN with the clinician managing your care before using it.

NMN and Pregnancy at a Glance

Question	What the evidence currently shows
Is NMN proven safe during pregnancy?	No. Adequate human pregnancy-safety trials have not been conducted.
Have pregnant people been included in NMN trials?	Pregnancy and breastfeeding are commonly exclusion criteria in human NMN studies.
Does NMN improve fertility?	Preclinical studies in aged mice report improved oocyte quality and fertility. Human oral fertility efficacy has not been established.
Does NMN help you get pregnant?	No controlled human trial has shown that oral NMN increases pregnancy rates or live-birth rates.
Is NMN safe while breastfeeding?	Supplement safety during breastfeeding has not been established.
Is NMN naturally present in breast milk?	Yes. NMN has been measured in human milk, but that does not establish the safety of supplemental NMN during lactation.
Is topical NMN pregnancy-safe?	Pregnancy-specific human safety data for topical NMN are lacking.
Is NMN the same as niacinamide?	No. NMN and nicotinamide/niacinamide are related NAD+ precursors but are different compounds.
Is NAD+ safe during pregnancy?	Do not assume so. NAD+ supplementation is a separate intervention and lacks adequate pregnancy-specific human safety evidence.

Can You Take NMN While Pregnant?

There is not enough human evidence to recommend NMN supplementation during pregnancy.

Most published NMN trials involve healthy or metabolically defined nonpregnant adults. Pregnant and breastfeeding participants are commonly excluded.

For example, a randomized NMN trial in hospitalized adults specifically excluded women who were pregnant, planning pregnancy, or breastfeeding.¹

This matters because pregnancy changes:

• blood volume;
• kidney function;
• liver metabolism;
• hormone concentrations;
• nutrient requirements;
• placental transport;
• fetal exposure to circulating compounds.

A supplement that appears well tolerated in healthy adults cannot automatically be assumed to have the same safety profile during pregnancy.

Is NMN Safe During Pregnancy?

Human pregnancy safety remains unestablished.

In 2026, the European Food Safety Authority evaluated chemically synthesized β-NMN as a novel food ingredient for supplements. The proposed target population was adults, explicitly excluding pregnant and lactating women.²

That exclusion is important. It does not prove that NMN is harmful during pregnancy. It means the available safety evidence was not considered sufficient to include pregnant or breastfeeding people in the assessed population.

The appropriate conclusion is therefore not:

• “NMN is dangerous during pregnancy.”
• “NMN is safe because it is naturally produced in the body.”

The accurate conclusion is:

Pregnancy-specific human safety has not been established.

Why Healthy-Adult NMN Studies Are Not Enough

Human NMN studies in nonpregnant adults have tested amounts such as:

• 250 mg per day for 12 weeks;
• 300 to 900 mg per day for 60 days;
• 1,250 mg per day for four weeks;
• higher short-duration doses of specific pharmaceutical-grade formulations.

These studies provide useful information about short-term tolerability in the populations tested.

They do not establish:

• placental transfer of supplemental NMN;
• fetal exposure;
• effects during organ development;
• effects on miscarriage risk;
• effects on birth defects;
• effects on fetal growth;
• effects on preterm birth;
• long-term effects on the child.

Pregnancy safety requires pregnancy-specific evidence.

What If I Took NMN Before I Knew I Was Pregnant?

If you used NMN before realizing you were pregnant, the existing research does not allow us to calculate a specific risk from that exposure.

There is also no human evidence showing that an accidental short exposure automatically causes harm.

The practical next steps are to:

• pause self-directed NMN use;
• contact your obstetric clinician or other pregnancy-care professional;
• provide the exact product label;
• tell them the amount you were taking;
• tell them how long you used it;
• mention any other supplements or medications you were taking at the same time.

Do not panic based on animal studies or online anecdotes. They cannot determine an individual pregnancy outcome.

What Do Animal Fertility Studies Actually Show?

Animal research is one reason NMN attracts interest in reproductive aging.

It is also one of the main reasons the pregnancy evidence is frequently overstated.

Aged-Mouse Fertility Research

A 2020 study examined declining fertility in reproductively aged mice.³

NMN supplementation increased NAD+ in oocytes and improved several measures involving:

• oocyte quality;
• embryo development;
• breeding performance;
• live-birth outcomes in aged mice.

These were mouse experiments, not human fertility trials.

The treatment amounts, reproductive biology, lifespan, and developmental timelines of mice differ substantially from those of humans.

Another 2020 Aged-Oocyte Study

A separate study reported improvements in meiotic competence, mitochondrial function, fertilization ability, and embryo-development potential in aged mouse oocytes after NMN treatment.⁴

Again, this is preclinical evidence.

It does not show that taking NMN:

• improves egg quality in women;
• increases human pregnancy rates;
• reduces miscarriage;
• improves IVF live-birth rates;
• is safe after conception.

Does NMN Improve Female Fertility?

Human oral fertility benefits have not been established.

Animal studies involving reproductive aging have shown potentially beneficial effects on oocytes and ovarian biology.

More recently, researchers studied NMN in mouse models of ovarian damage and also performed laboratory experiments using immature oocytes obtained from women with advanced maternal age.⁵

In that study, NMN was added directly to the laboratory culture medium containing immature human oocytes. Researchers reported changes in nuclear competence and artificial activation.

This was in-vitro treatment of isolated human oocytes.

It was not a trial in which women:

• took oral NMN;
• attempted natural conception;
• underwent pregnancy follow-up;
• had pregnancy or live-birth rates measured after supplementation.

The study therefore cannot establish an oral fertility treatment.

Can NMN Help You Get Pregnant?

No controlled human study has shown that an NMN supplement increases the likelihood of conception.

Claims that NMN “rejuvenates eggs” or “restores fertility” usually come from aged-mouse studies.

Those findings justify further research. They do not establish a clinical fertility recommendation.

If fertility is the goal, evidence-based evaluation should focus on factors such as:

• age;
• ovulation;
• ovarian reserve;
• fallopian-tube factors;
• endometriosis;
• sperm quality;
• medications;
• underlying endocrine conditions.

NMN should not replace a fertility evaluation.

Should You Stop NMN When Trying to Conceive?

There is no human evidence establishing an ideal NMN preconception protocol.

Animal fertility findings do not answer whether ongoing supplemental NMN exposure is safe during early human embryonic development.

Because pregnancy can begin before it is recognized, a conservative approach is to avoid self-directed NMN while actively trying to conceive unless your fertility or obstetric clinician recommends otherwise.

This is especially relevant for people undergoing:

• ovulation induction;
• IVF;
• egg retrieval;
• embryo transfer;
• other assisted-reproduction treatment.

Your fertility team should know every supplement you are taking.

Does NMN Increase Estrogen?

NMN has not been established as an estrogen-raising supplement in humans.

Some animal ovarian-aging studies report changes in reproductive hormones after NMN treatment, but those results should not be translated into a claim that NMN raises estrogen in women.

Human estrogen levels vary with:

• age;
• menstrual-cycle phase;
• pregnancy;
• menopause;
• medications;
• fertility treatment;
• endocrine conditions.

NMN should not be used to manipulate reproductive hormones without clinical guidance.

Is NMN Safe While Breastfeeding?

The safety of supplemental NMN during breastfeeding has not been established.

This question has an interesting complication: NMN occurs naturally in human breast milk.

A 2023 cohort study measured NAD-related compounds in milk samples from 150 Japanese mother-infant pairs.⁶

NMN was the most abundant NAD-related precursor measured in those milk samples, with a median concentration of 9.2 µM.

The researchers also observed an association between breast-milk NMN concentration and one later neurodevelopmental measure.

This study did not test maternal NMN supplementation.

It therefore does not establish:

• that taking an NMN supplement during breastfeeding is safe;
• how much supplemental NMN would appear in breast milk;
• how maternal dose affects infant exposure;
• what supplemental dose would be safe for the infant.

The presence of a compound naturally in breast milk does not mean that taking a concentrated supplement is automatically safe during lactation.

Why Is Natural NMN in Breast Milk Different From an NMN Supplement?

The body regulates naturally occurring NAD-related metabolites.

A supplement can provide an exposure that differs from normal physiology in:

• amount;
• timing;
• peak blood concentration;
• duration of exposure;
• metabolic conversion.

Breast-milk composition can also change with:

• time postpartum;
• maternal diet;
• metabolism;
• health status;
• time of day.

Natural presence and supplemental safety are different questions.

Is Topical NMN Safe During Pregnancy?

Pregnancy-specific human safety data for topical NMN are lacking.

A topical product may produce less systemic exposure than an oral supplement, but that does not automatically establish pregnancy safety.

Absorption can depend on:

• NMN concentration;
• finished-product formulation;
• delivery system;
• application area;
• frequency of use;
• skin-barrier condition;
• other ingredients in the product.

Without pregnancy-specific data for the finished topical formula, it is not appropriate to label topical NMN universally pregnancy-safe.

Is Topical NMN the Same as Niacinamide?

No.

This distinction is especially important because searches for topical NMN often return information about niacinamide.

NMN and nicotinamide—commonly called niacinamide in skincare—are related to vitamin B3 and NAD+ metabolism, but they are chemically different compounds.

Evidence or pregnancy guidance for topical niacinamide should not automatically be transferred to topical NMN.

Is Nicotinamide the Same as NMN During Pregnancy?

No.

Nicotinamide is an established form of vitamin B3. NMN is a downstream NAD+ precursor molecule.

Pregnancy nutrient recommendations for niacin or nicotinamide do not establish a safe supplemental NMN amount.

This is a common entity-transfer error:

• vitamin B3 is required during pregnancy;
• NMN participates in vitamin-B3-related NAD+ metabolism;
• therefore NMN supplements must be beneficial during pregnancy.

That conclusion does not follow from the evidence.

Can You Take NAD+ While Pregnant?

NAD+ supplements are a separate intervention from NMN.

The fact that NAD+ is naturally present in every cell does not establish the safety of concentrated oral, injectable, intravenous, subcutaneous, or other supplemental NAD+ products during pregnancy.

Pregnancy-specific human safety evidence for NAD+ supplementation is also inadequate.

Do not substitute a NAD+ product for NMN during pregnancy on the assumption that it must be safer because NAD+ occurs naturally in the body.

What About NMN Side Effects During Pregnancy?

The main problem is not a known pregnancy-specific NMN side-effect profile.

The problem is that such a profile has not been adequately studied.

Human adult NMN trials have generally reported acceptable short-term tolerability, but those findings do not answer:

• placental effects;
• fetal exposure;
• effects on fetal organ development;
• effects on miscarriage risk;
• pregnancy-specific metabolism;
• effects on breastfeeding infants.

For nonpregnancy safety evidence, see our NMN side effects and safety guide.

What If a Product Says NMN Is “Natural”?

“Natural” is not a pregnancy-safety category.

NMN occurs naturally in human metabolism and in small amounts in some foods and human milk.

A concentrated supplement is still a distinct exposure.

The relevant questions are:

• Has the finished product been studied during pregnancy?
• What amount is being taken?
• How much systemic exposure occurs?
• Does it cross the placenta?
• What fetal-development data exist?

For supplemental NMN, those pregnancy-specific questions remain inadequately answered.

Are NMN Supplements FDA-Approved for Pregnancy?

No NMN supplement is FDA-approved as a treatment to improve fertility, support pregnancy, prevent miscarriage, or improve fetal development.

Dietary supplements are not reviewed and approved by FDA for safety and effectiveness before marketing in the way prescription drugs are.

A product being sold legally does not mean it has been demonstrated safe during pregnancy.

What Supplements Should You Use Instead?

NMN should not be replaced with a random “anti-aging” supplement during pregnancy.

Pregnancy has specific, evidence-based nutritional requirements.

Common prenatal considerations include nutrients such as:

• folic acid;
• iron;
• iodine;
• vitamin D;
• choline;
• calcium;
• omega-3 fatty acids where appropriate.

The appropriate amounts depend on diet, age, health history, laboratory results, medications, and pregnancy circumstances.

These nutrients should not be described as direct “alternatives to NMN.” They are established pregnancy-nutrition considerations with different biological purposes.

Who Should You Talk to About NMN During Pregnancy?

Depending on your situation, appropriate professionals may include:

• your obstetrician or midwife;
• a maternal-fetal medicine specialist;
• your fertility specialist;
• a pharmacist;
• a registered dietitian experienced in pregnancy.

Bring the exact NMN product with you or provide:

• the Supplement Facts panel;
• amount per serving;
• number of servings taken daily;
• complete ingredient list;
• how long you have used it;
• all other medications and supplements.

Frequently Asked Questions

Can you have NMN while pregnant?

Human pregnancy safety has not been established. Because pregnant people are generally excluded from NMN trials, self-directed NMN supplementation during pregnancy is not advisable without guidance from the clinician managing the pregnancy.

Is NMN safe during pregnancy?

There is not enough human evidence to call NMN pregnancy-safe. Available adult safety trials do not establish fetal or maternal safety during pregnancy.

Can NMN help you get pregnant?

Animal studies report improvements in aged-mouse oocytes and fertility, but no controlled human oral trial has shown that NMN increases conception or live-birth rates.

Does NMN make you more fertile?

That has not been established in people. Most positive fertility findings come from aged mice or laboratory studies involving isolated oocytes.

Should I stop NMN when trying to conceive?

There is no validated preconception protocol. Because pregnancy can begin before recognition and human early-pregnancy safety data are lacking, discuss ongoing NMN use with your fertility or obstetric clinician before conception.

Is NMN safe while breastfeeding?

Supplement safety during breastfeeding has not been established. NMN occurs naturally in human breast milk, but that does not prove concentrated maternal supplementation is safe for the nursing infant.

Is topical NMN safe during pregnancy?

Pregnancy-specific human data for topical NMN are lacking. Topical exposure may differ from oral use, but finished-product absorption depends on formulation and use conditions.

Is topical nicotinamide the same as topical NMN?

No. Nicotinamide, often called niacinamide in skincare, and NMN are different molecules. Pregnancy evidence for one should not automatically be transferred to the other.

Does NMN raise estrogen?

NMN has not been established as an estrogen-raising supplement in human trials. Animal reproductive findings do not establish a predictable hormonal effect in women.

Can I still take NAD+ while pregnant?

NAD+ supplementation is different from NMN and also lacks adequate pregnancy-specific human safety data. Do not assume it is safe simply because NAD+ naturally occurs in the body.

What if I accidentally took NMN while pregnant?

Human evidence does not allow a specific risk estimate from inadvertent exposure. A few doses do not automatically mean harm occurred. Pause self-directed use and contact your pregnancy-care professional with the exact product, amount, and duration of exposure.

Is NMN safe during IVF?

Human evidence is insufficient to recommend oral NMN routinely during IVF. Animal and laboratory oocyte research is not the same as demonstrating improved human IVF outcomes or pregnancy safety. Discuss supplement use with the fertility clinic before treatment.

Are there benefits of NMN during pregnancy?

No clinical benefits of supplemental NMN during human pregnancy have been established. Animal fertility and embryo studies should not be presented as pregnancy benefits in people.

The Bottom Line

NMN pregnancy safety has not been established in humans.

The evidence currently supports several clear conclusions:

• pregnant and breastfeeding people are generally excluded from NMN clinical trials;
• adult NMN safety studies cannot establish fetal or pregnancy safety;
• animal studies show interesting effects on aged oocytes and fertility, but these are not human pregnancy trials;
• laboratory findings involving human oocytes do not establish that oral NMN improves fertility;
• NMN naturally occurs in human breast milk, but that does not prove maternal supplementation is safe while breastfeeding;
• topical NMN does not have adequate pregnancy-specific human safety evidence;
• NMN is not the same compound as nicotinamide or topical niacinamide;
• NAD+ supplementation should not be assumed pregnancy-safe simply because NAD+ is naturally present in the body.

If you are pregnant, breastfeeding, or actively trying to conceive, the appropriate question is not whether NMN looks promising in aging-animal research. It is whether there is enough human reproductive-safety evidence for your situation.

At present, that evidence is insufficient.

For general adult safety, see NMN side effects. For human-study amounts, see our NMN dosage guide. For the broader evidence base, see NMN benefits and how it works.

References

1. Pencina KM, Leaf DE, Valderrabano RJ, et al. Oral MIB-626 (β Nicotinamide Mononucleotide) Safely Raises Blood Nicotinamide Adenine Dinucleotide Levels in Hospitalized Patients With COVID-19 and Acute Kidney Injury: A Randomized Controlled Trial. FASEB BioAdvances. 2025;7(8):e70011. PMID: 40746868.
2. EFSA Panel on Nutrition, Novel Foods and Food Allergens. Safety of beta-nicotinamide mononucleotide pursuant to Regulation (EU) 2015/2283 and the bioavailability of nicotinamide from this source. EFSA Journal. 2026;24(5):e10007. PMID: 42125559.
3. Bertoldo MJ, Listijono DR, Ho W-HJ, et al. NAD+ Repletion Rescues Female Fertility during Reproductive Aging. Cell Reports. 2020;30(6):1670–1681.e7. PMID: 32049001.
4. Miao Y, Cui Z, Gao Q, Rui R, Xiong B. Nicotinamide Mononucleotide Supplementation Reverses the Declining Quality of Maternally Aged Oocytes. Cell Reports. 2020;32(5):107987. PMID: 32755581. doi:10.1016/j.celrep.2020.107987.
5. Nicotinamide mononucleotide supplementation improves oocyte developmental competence in different ovarian damage conditions. American Journal of Obstetrics & Gynecology. 2025. PMID: 39923879.
6. Saito Y, Sato K, Jinno S, et al. Effect of Nicotinamide Mononucleotide Concentration in Human Milk on Neurodevelopmental Outcome: The Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. Nutrients. 2023;16(1):145. PMID: 38201974. doi:10.3390/nu16010145.
7. National Institutes of Health, Office of Dietary Supplements. Dietary Supplements and Life Stages: Pregnancy—Fact Sheet for Health Professionals.
8. American College of Obstetricians and Gynecologists. Good Health Before Pregnancy: Prepregnancy Care.