Maca Pregnancy & Breastfeeding Safety + Side Effects

Maca is a famous adaptogen and tonic native to the Peruvian highlands. If you’re trying to conceive, are pregnant, or breastfeeding, you’ve probably become a victim of the maca craze! 

How much do we know about the safety of maca? 

Get ready for the most detailed maca safety report on the internet. I’ll break down—and tear apart!—all the research data that exist about the safety and side effects of maca in pregnancy and breastfeeding.  

Disclaimer: This post is for informational purposes only. None of the information here should be taken as medical advice. Even if a remedy is classified as safe in Herbal Doula blog posts based on the existing evidence, that doesn’t mean it’s safe for you. The classifications in the database are just a general reference point. Follow your body, keep track of your response, and consult an herbalist, holistic practitioner, traditional midwife, or anyone else you feel may help you if you need expert advice. 

The Dilemma of Maca in Birth Work… 

To me, maca opened Pandora’s box of adaptogens in birth work. Are they safe? When? Which ones?

So, this post is all about maca’s safety and side effects. I’ve compiled the evidence on the benefits of maca across the spectrum of women’s health in a separate post (hint: you’ll find out if it can really boost fertility and milk supply). 

I’ve been asked numerous times about whether maca can be used during pregnancy and breastfeeding. I didn’t have an answer. 

Both popular posts and professional sources are filled with conflicting information. Blog posts boast about maca’s alleged benefits postpartum, and some even recommend it in early pregnancy. 

Wouldn’t it be great to have a superfood that can balance mood and hormones during those intense moments of early pregnancy and postpartum? Sure sounds tempting.

Textbooks and professional databases are on the other end of the spectrum. They recommend against maca altogether due to a lack of safety data. 

So, where is the truth?

As with most natural remedies, it’s likely somewhere in between. 

Maca Safety Categorization

Learn about Herbal Doula’s transparent research process for categorizing the safety of natural remedies here.  

Pregnancy Safety: Caution 

Labor Safety: Unknown

Breastfeeding Safety: Caution  

Maca should be used with caution while pregnant or breastfeeding and preferably under the guidance and supervision of a qualified care provider (ND/MD/midwife/herbalist). 

Maca use during pregnancy should be highly limited due to a lack of safety data and maca’s possible effects on hormones and uterine bleeding. 

If recommending maca, it’s important to choose a trusted brand that sources organic, pure maca. 

Ask for third-party quality testing data due to potential heavy metals and pesticide contamination. These and other impurities are especially dangerous during pregnancy and breastfeeding. ¹ 

Maca’s safety categorization in breastfeeding and pregnant women relies on one study ² that included a Peruvian population that traditionally grows and uses maca as food. 

Anthropological data from studies and herbal medicine books on traditional maca use in pregnancy and breastfeeding are sparse. 

The European Medicines Agency (EMA) does not have a monograph on maca. Maca is not mentioned in several reviews of the literature on the use of herbal supplements in pregnancy. ^3–5 

There are no reports of maca having adverse effects on mother or baby in pregnancy or breastfeeding, with the exception of one case report ¹ of maca lead contamination. 

Controlled human studies are needed to determine the safety of maca in pregnant and breastfeeding populations. 

There are no data on maca use in labor. 

Maca Traditional & Modern Uses 

Traditional Use in the General Population

Several indigenous South American communities consider maca an important traditional remedy. 

Folk healers view it as a nutrient-dense food, adaptogen, tonic, nootropic, and aphrodisiac that increases stamina and energy. They also use it for respiratory disorders, rheumatism, and as an antiseptic. ^6,7 

Maca is traditionally dried naturally after being harvested. Once dried, maca becomes “as hard as stone,” which allows it to be stored for many years. 

Maca is then boiled and cooked to soften it. It can be further fermented as a drink (maca chicha), made into porridge, or prepared as a soup. Fresh maca can also be baked or roasted. ^7,8 

According to some researchers, maca as food is biologically adapted to provide nutrients and active compounds in the harsh conditions it grows in. ⁸

In general, people indigenous to the Peruvian highlands recommend exposing maca roots to high temperatures before use because fresh maca may be detrimental to health. They consume about 20 g (0.7 oz) per day. No adverse reactions have been reported in people who traditionally eat maca as food. ^2,7 

The effects of fresh maca on health have not been scientifically assessed yet.

Most of maca’s traditional uses haven’t been studied scientifically. 

Traditional Use for Women’s Health

Indigenous people use maca as a fertility enhancer for both humans and cattle, to heal wounds, stimulate menstrual flow, and for anemia. ^6,7 

Father Cobo, a Spanish missionary, was the first non-indigenous person to describe maca, its properties, and its use for fertility in the 17th century. ^8,9

Modern Uses

People use maca for a variety of reasons, but proper research is still lacking to support its effectiveness.

Since maca was introduced to the West in the 2000s, its popularity has soared. 

Maca has been promoted as a wonder food for libido and fertility enhancement, erectile dysfunction, and benign prostatic hyperplasia. Some people even use it for stomach and blood disorders and as an immune booster. 

Companies also market maca for enhancing athletic performance, focus, and memory. 

Women are the main consumers of maca. 

Blogs and forums mention its use for hormonal imbalances, recurrent early miscarriages, menstrual irregularities, milk supply,  menopausal symptoms, osteoporosis, mood imbalances, and chronic fatigue syndrome (CFS).

Much of the hype lacks evidence. ¹⁰ 

Curious to know more?

Head over to this article that specifically breaks down the benefits of maca for women’s health. 

The Pitfalls of Maca Mass Production 

As maca became the next big superfood, local communities in Peru struggled with a huge worldwide demand for a crop they never lacked. Traditional plant cultivation methods were no longer enough as the market demanded mass production. 

Companies started using fertilizers and pesticides, and much of maca is now grown in Yunnan province in China. ¹⁰ 

Many local producers in Peru are suffering serious consequences. Also, their indigenous knowledge has been dragged out of context to fit the market demands. On top of everything, there are no clear protocols to regulate maca production and marketing. ¹⁰ 

Sustainably grown and traditionally cultivated maca and its mass-produced counterpart are not the same. They differ in active compounds, nutrients, contaminants, and more. ¹⁰ 

Herbal Astrology & Alchemy

This part is not evidence-based, it’s just for fun!

In herbal astrology, maca is associated with Mars (the governing planet of the signs Aries and Scorpio). Mars is related to energy, passion, fertility, and sexuality. It’s also connected to bile and the pancreas.

Maca’s element is thought to be fire.

It’s said to cleanse the 3rd (solar plexus) chakra.

Maca Research in Pregnancy & Breastfeeding 

Limitations 

There’s a big need for maca research in women. Reliable data on the safety and effects of maca on pregnant, laboring, or breastfeeding women is lacking. 

The majority of human research on maca was done in men, mainly to test for its effects on sperm quality, prostate health, or erectile dysfunction. Even preclinical experiments mostly used male animals.

Peruvian Maca Study 

Only one published study investigated maca use as a staple in a population that may have included pregnant and breastfeeding women. ²  

The study surveyed people living in the Peruvian central Andes (Carhuamayo, 4100 m), 80% of which traditionally consume maca. Maca-eaters were compared to the remaining minority that lives in the same area and does not consume maca.

The study included people 35 to 75 years old, of both genders, without excluding pregnant or breastfeeding women ². 

Members of this community start eating maca in childhood, mainly after it is naturally dried; 85% take it for nutritional reasons. 

Maca-eaters had normal liver and kidney function, lipid profile, and blood sugar. Maca consumption was associated with better health status scores, lower rates of fractures, lower rates of chronic mountain sickness, lower BMI, and lower systolic blood pressure. 

To sum it up, the authors concluded that eating maca as food is safe in this population.

However, it’s unknown how many women in this study were pregnant or breastfeeding; more could be expected in the age group under 35 years. Also, other factors like genetics or culture could have contributed to the results. 

Although no sources suggest that Peruvian women stop eating maca in pregnancy or postpartum, it’s impossible to determine the safety of maca based on this study and anecdotal information only. 

Challenges Women in the Peruvian Highlands Face

There are many factors specific to communities in the Peruvian highlands. Even if research were to determine the safety and effectiveness of maca in this population, the data could not be applied to people in other parts of the world. 

For one, maintaining pregnancy at 14,000 feet is an awe-inspiring feat. 

According to recent research in humans and animals, high altitude may affect reproductive health and even raise estrogen in pregnancy after several generations. ^11,12

Field studies from the 60s report pregnant women living at 14,000 ft (~4,200m) had smaller babies and placentas. ¹³ 

It’s impossible to avoid hypoxia (low oxygen) at high altitudes. Hypoxia may lead to oxidative stress and altered stress hormones and reproductive hormones. ¹¹  

Yet, not all people indigenous to high altitudes are less fertile than people living at low altitudes. It seems that long-standing communities have adapted to high-altitude conditions and hypoxia, but those who migrate to high altitudes report reproductive challenges. ¹⁴

Behavioral, sociocultural, and environmental factors that are hard to control may also affect fertility in these populations. For example, local beliefs about baby feeding and prolonged breastfeeding seem to impact fertility in Andean populations more than altitude. ¹⁴ 

Animal Studies

No adverse effects on pregnancy or fetal development have been observed in animal studies with daily doses up to 1g/kg. ^8,15–18

(Have in mind that animal dosages and study results can’t be extrapolated to humans, though!)

In one study, diets made up of 30% maca throughout pregnancy and breastfeeding increased litter size in mice without adverse effects on fetal development or offspring growth. ¹⁹

Mice given 1 g/kg of freeze-dried maca water extract on days 1 to 4 of pregnancy experienced no adverse effects on implantation or on fetal development in another experiment. ¹⁶

Also, female mice that drank water with maca extract for 30 days (5 g maca/100 ml water) had higher progesterone and testosterone levels but estradiol stayed the same. Embryo implantation rates after mating didn’t change. ¹⁷

One Peruvian research team gave healthy female mice maca water extract before, during, and after pregnancy. In this study too, maca increased litter size. No adverse effects throughout this period (or changes to implantation) were noted. ¹⁸ 

Can Maca Pass Into Breast Milk?

Some of maca’s active compounds may pass into breast milk. It’s uncertain to what extent and whether they can impact the health of breastfed babies. 

Maca contains plant sterols, such as beta-sitosterol, which is a phytoestrogen. Phytoestrogens are plant compounds that mimic the effects of estrogen in the body. ²⁰ 

A small 1976 study found that some plant sterols may cross the placenta before birth. They also showed that vegetable-oil formula-fed babies had built-up plant sterols in their arteries, which can be harmful. Clinical trials have yet to be carried out. ²¹ 

Vegetable oils in formula may be problematic for babies, but that doesn’t mean plant sterols that may pass into breast milk are bad. The body can transform and disperse fats from vegetables into breast milk to make them super absorbable and useful for babies. ²² 

Can Maca Cross the Placenta?

According to rat experiments, plant sterols like genistein from soy may cross the placenta and enter the fetal brain. ²³ 

Plant sterols are a normal part of many diets around the world. Even if they can reach the fetus via the placenta or baby via breast milk, there is no clear evidence that can do harm. 

The Plant Sterols Controversy

Plant sterols are being investigated as natural cholesterol-lowering remedies. Animals with high cholesterol levels (lacking ApoE or eating a high-cholesterol diet) supplemented with plant sterols gave birth to pups with an improved lipid response. ^24,25 

Maca’s plant sterols are even being researched for balancing the stress response axis. ²⁶

However, other lines of new research suggest that plant sterols might be harmful for some people. ^27,28 

About 25% of the population is genetically prone to absorbing cholesterol in excess (cholesterol hyperabsorbers). People who fall in this group might suffer cardiovascular side effects from a diet high in plant sterols. ^27,28

More research is needed, but this warrants some caution. 

If you have had problems with high cholesterol, you may want to talk to your provider about running additional blood work and genetic tests to see if you should be concerned about plant sterols in food in general. 

Have in mind that the amount of plant sterols you would be getting from maca is tiny. It would be in the range of up to 0.06 g if you take 3 g of dried maca per day. ^8,29 

Maca Side Effects Research & Precautions

Uncooked maca

Eating fresh, uncooked maca may cause stomach pain. ⁸ 

Liver Enzymes

In one study in patients with metabolic syndrome, maca at a dose of 0.6 g/day for 90 days increased liver enzymes (AST) and diastolic blood pressure. ³⁰ Increased liver enzymes may signal liver damage. 

Estrogen-Like Effects

Scientists argue about whether maca has estrogen-like activity or not. 

Cell-based experiments suggest it does. ³¹ 

Animal and human experiments suggest it doesn’t. ⁸ 

More clinical trials are needed to say for sure. 

Women with hormone-sensitive conditions (like breast cancer, endometriosis, and others) uterine fibroids should have maca’s potential estrogenic activity in mind and consult a doctor before supplementing.

Bleeding Between Cycles & Testosterone-Like Compounds

One case study describes a young woman who was using maca to increase energy levels and libido. After a couple of months, she experienced prolonged bleeding between menstrual cycles and was referred to an endocrine clinic. ³² 

Tests picked up high blood testosterone (25.8 nmol/l). She didn’t have any symptoms of high testosterone, though, which left doctors confused. 

Also, maca use didn’t affect testosterone in mice and human studies.

The doctors suspected that something else similar to testosterone in maca was responsible for a false high testosterone test result. They repeated the test with better sensitivity, and it turned out that her testosterone level was normal.

The testosterone-like compound researchers were on the search for in this case study has yet to be identified. Compounds in maca might activate testosterone receptors in the body and have masculinizing effects without raising testosterone in the blood, which warrants caution.

Lead Contamination

One case of unintentional lead exposure from a store-bought ceramic mug and a maca supplement has been reported. ¹ 

The case involved a 32-year-old woman with a high blood lead concentration (44 μg/dL). Her initial source of exposure was lead leaching from a ceramic mug she used to drink hot lemon water while she was pregnant. 

She stopped drinking from the mug and her blood lead levels decreased but increased a year later after she began taking maca root powder while breastfeeding. Upon stopping maca, her blood lead levels decreased further. 

Lead poisoning is rare in pregnancy and it may lead to an increased risk of spontaneous abortion. ¹ 

Risk factors for lead exposure in pregnant women include the use of imported herbs, spices, or cosmetic products, certain “risky” hobbies (e.g., stained glass production, pottery, painting), or a personal history of previous lead exposure. ¹ 

Drug Contamination

In 2019 the FDA reported that one brand of maca (“Peru Maca”) was tainted with sildenafil, the active ingredient in Viagra. 

MTCA

One study found a compound labeled MTCA in maca. One research group suggested MTCA may be toxic to the cells and nervous system. In turn, the French Agency of Sanitary Security issued a warning about maca. ³³

However, fruits like oranges and grapefruit and fruit juices also contain MTCA, so it’s unlikely to be dangerous. ⁸ 

Fermented garlic extract also builds up MTCA with aging, suggesting that MTCA might even be an antioxidant, but this is uncertain. ⁸  

Other Reported Side Effects

Side effects reported by maca users include menstrual cycle irregularities, stomach cramps, moodiness, and insomnia. ³⁴

Anecdotally, maca may also change the taste of breast milk. Many foods can change the taste of breast milk, and this alone is rarely a cause for concern. 

What Is the Bottom Line?

• People in the Peruvian Andes likely eat maca as nutrient-dense food throughout life
• You can use organic maca with caution during pregnancy and breastfeeding preferably after consulting a knowledgeable care provider
• Monitor your response maca 
• Stop taking maca if you experience any unwanted effects (like cramps or bleeding between cycles)
• Stay away from low-quality maca; it may contain heavy metals, pesticides, other toxins, and even drugs

>>>>>     Continue reading about the benefits of maca for women’s health (including dosage and the types of maca supplements that are out there). 

Did you consider using maca while pregnant or breastfeeding? What did your care provider recommend? 

Let me know about your experience in the comments and share this article if you found it useful!

References (✔ Trusted Sources)

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