Be Picky About Which Prenatal Vitamins You Choose!

Key Takeaways

• Prenatal vitamins commonly contain unsafe levels of heavy metals and toxic chemicals, including lead, arsenic, cadmium, mercury, and phthalates.
• A growing fetus/baby is at particular risk of being exposed to heavy metals in utero.
• The FDA is not sufficiently testing for, monitoring, and regulating prenatal vitamins to prevent such contamination.
• It is possible for companies to ensure their products do not contain heavy metals, but they have no incentive to do so, given the lack of oversight and regulation.

My Story

When I was pregnant, my OB mentioned that pre-natal vitamins were something I should be consuming. I asked him if he had one brand over another he preferred. He didn’t, though said that the main thing is to ensure that some key ingredients like iron and folate were part of the pill, without providing specific target amounts.

So I did my own research to get a better sense of which vitamins/minerals were most critical and in what minimum amounts. Then I went to Whole Foods, found the organic options, read the vitamin/mineral contents and the other ingredients (I wanted to avoid any with rice, given what I knew about arsenic in rice products), and then picked one that looked to be pretty good. 

My daughter is now 6, and it wasn’t until a few months ago that I learned that the majority of pre-natal vitamins contain unsafe levels of heavy metals and toxic chemicals. Uh-oh.

I had come across test results for specific brands of prenatal vitamins on the Lead Safe Mama website, a mission-oriented consumer advocacy organization developed by Tamara Rubin to help other parents reduce the risks of exposure to lead for their children. I took a deep breath as I pulled up the web page with the results of those tests, and, unfortunately, the one I had been taking throughout pregnancy and breastfeeding did not have good test results. It was:

• The highest of the group in alarming levels of arsenic at 1100 ppb vs the recommended <5ppb
• One of the highest in lead, at 94 pbb vs recommended <10 ppb
• At an unsafe level of cadmium, at 48 ppb, relative to a recommended <5 ppb.

Boy, am I mad that this company was able to get away with this and that no one was minding whether these pills had contaminants in them that could harm a growing fetus/baby. And same for all of the other offenders on the list!

The more I dug in, the more I learned that the presence of heavy metals in prenatal vitamins has been known for several years. The study that dates back the furthest (from what I could find) was 2008. 

The Science

Per one of the most recent and comprehensive studies on heavy metals and toxic chemicals found in prenatal vitamins (Gardener et al. 2025):

“Fetal development is a vulnerable period for exposures to toxicants, including heavy metals and endocrine disrupting compounds (EDCs). Exposure to heavy metals (e.g. lead and cadmium) and EDCs (e.g. phthalates) in utero have been shown to result in pregnancy complications and impairments in neurodevelopment, cognitive and behavioral health, growth, metabolic and cardiovascular health, and reproductive health throughout childhood (Skogheim et al., 2021; Freire et al., 2018; Young and Cai, 2020; Moynihan et al., 2019; Chandravanshi et al., 2021; Hu et al., 2006; Taylor et al., 2015; Lu et al., 2023; Guo et al., 2022; Huang et al., 2022; Nozadi et al., 2021; Perez-Diaz et al., 2024; Cohen-Eliraz et al., 2023; Dewey et al., 2023; Yang et al., 2023; Jin et al., 2023; Gao et al., 2023; Su et al., 2023; Mariana et al., 2023; Coiffier et al., 2023; Tsai et al., 2023; Qian et al., 2020).”

“Several recent studies have explored prenatal vitamins as a source of heavy metal exposure during development (Schwalfenberg et al., 2018; Zhang et al., 2023; Canale et al., 2021), particularly because they are ingested daily for months on end by most pregnant people. Indeed, several studies have found prenatal vitamins are a significant source of maternal and fetal exposure to toxic metals (Schwalfenberg et al., 2018; Zhang et al., 2023). At present there are no limits on the amount of these metals allowed in prenatal vitamins in the United States.

“While illustrative, prior heavy metals studies have included very small sample sizes, limiting broad applicability and our understanding of the extent of supplement contamination exposed to most pregnant people and the extent of contamination of prenatal vitamins with phthalates is unknown. Therefore, the goal of the current study is to characterize the contamination of 156 distinct commercially available prenatal vitamins, nine prescription prenatal vitamins, and 19 folate or folic acid supplements with lead, cadmium, and phthalates.”

“Lead, cadmium, and phthalates are clinically relevant and ubiquitous environmental toxicants to which pregnant people are frequently exposed in the United States and globally (Gardener et al., 2022; Thilakaratne et al., 2023; Geron et al., 2022). Phthalates represent a class of plasticizers that are frequently added to plastics, including tubing and packaging, as well as fragranced personal care and cleaning products.”

This study found that:

• Heavy metal contamination in prenatal vitamins may counter-balance their health benefits.
• 83% of commercially available prenatal vitamin samples had quantifiable lead (15% > 0.5 μg/serving), 73% had cadmium.
• 15% exceeding the California Proposition 65 threshold for daily lead consumption (0.5 μg).

You can find a helpful summary of this study in an article written by Unleaded Kids, found here.

“There is no identified threshold or safe level of lead in blood below which no risk of poor developmental or intellectual function is expected.”(CDC)

Lead is of particular concern because, as the CDC highlights repeatedly on its website: “No safe level of lead in children has been identified. Even low levels of lead in blood have been shown to reduce children’s IQ, ability to pay attention, and academic achievement. Because any blood lead level can harm children, our focus is on eliminating exposure in the first place.” (CDC) 

The FDA also states that there is no safe level of lead for children. In spite of this, their current guidance on daily lead intake is an interim reference level (IRL) of 2.2 micrograms (µg) per day for children and 8.8 µg per day for females of childbearing age. .

According to a study undertaken by GA Wasserman et all in 2000,  Elevations in both prenatal and postnatal BPb (blood lead levels) were associated with small decrements in young children’s intelligence. And, in fact, “the effects of prenatal exposure to lead were proportionally greater at lower levels of exposure.”

What You Can Do

Clearly the FDA is not looking out for us as they should, so it is up to us to manage the risks. Here are the ways that you can do so:

• Be as informed as possible. Use what information exists thanks to consumer advocates like Tamara Rubin via her Lead Safe Mama website, since the studies mentioned above do not share detailed test results or the specific brands they tested.
• If you feel strongly enough about this to take further action, you can let the FDA know via this link.
• You can also reach out to your state government representatives to encourage them to follow the lead of California in passing legislation to regulate amounts of heavy metals and toxic chemicals in prenatal vitamins.
• You can help raise awareness among other families and in particular of which brands to avoid, to both help others and put pressure on the offending companies.

Making Informed Choices

In terms of making an informed decision for yourself and your family, use the information shared on Lead Safe Mama to identify which on the list have the lowest levels of each contaminant. Or, perhaps you know of another brand that you trust and has been tested for heavy metal contamination.

But, if you want to be extra cautious, keep in mind that levels tested may vary from batch to batch. If you’d like to conduct a second test of a batch you buy yourself, you can do so, and use Simple Labs test kit to have a third party independent lab do the testing. It isn’t cheap, but if you can afford it, it may be worthwhile to ensure you are keeping your baby safe from some of the worst toxicants.

Positive Actions at the State Level

The good news is that, where the federal government fails us, several states have stepped up, in particular California, who leads the pack in terms of trying to protect its citizens from dangerous exposure to toxic chemicals.

California Senator Weber Pierson, a board-certified obstetrician/gynecologist in San Diego, introduced SB 646 to require manufacturers to test each batch of prenatal vitamins they sell in the state for arsenic, cadmium, lead, and mercury. Starting January 1, 2027, the companies would be required to disclose the test results on their website and add a QR code to their label to make it easy for consumers to access the information.

What is great about this bill is that it is intended to:

• Empowering pregnant people with sufficient information to make choices about the prenatal vitamins they buy; and
• Creating marketplace incentives for companies to compete for the lowest level of contamination.

Presumably, companies that adjust their manufacturing processes to meet these new regulations will in turn be offering the same products to other states in the nation, so that we all benefit. Until then, we are reliant on imperfect information to make the best decisions we can.