Commercially Available Prenatal Vitamins Do Not Meet American College of Obstetricians and Gynecologists Nutritional Guidelines

Abstract

Objective

This study aimed to evaluate the reported amount of the American College of Obstetricians and Gynecologists (ACOG) recommended nutrients in commercially available, over-the-counter prenatal vitamins (PNVs) in the United States, to assess their adequacy compared with the ACOG guidelines, and to compare these supplements by cost.

Study Design

The top 30 online Amazon and Google shopping items found using “prenatal vitamins” in September 2022 were included for analysis if they included the words “prenatal” and “vitamin” in the label and contained multiple nutrients. Duplicates between Amazon and Google were excluded as well as vitamins that did not list all ingredients. The reported amounts of 11 key nutrients, as recommended by the ACOG, for each product were recorded, as well as supplemental form and cost per 30-day supply. A cost analysis was done of PNVs that met the ACOG recommendations for the highlighted nutrients compared with those that did not. Five out of the 11 key nutrients (folic acid, iron, docosahexaenoic acid, vitamin D, and calcium) were specifically highlighted, as deficiencies in these nutrients are known to correlate with significant clinical outcomes in pregnancy.

Results

A total of 48 unique PNVs were included for final analysis. Of these PNVs, none were compliant with suggested amounts of all five key vitamins and nutrients. No products met daily recommendations for calcium. Only five PNVs were compliant with recommendations with ⅘ key nutrients. Of note, 27% of PNVs did not have the recommended amount of folic acid (13/48). The median cost of PNVs that were not compliant with the four nutrients mentioned above was $18.99 (interquartile range [IQR]: $10.00–$30.29), which was not statistically different from the median cost of the PNVs that did meet compliance with the four nutrients, which was $18.16 (IQR: $9.13–$26.99), p = 0.55.

Conclusion

There were significant variations in the level of nutrients and cost of commercially available, over-the-counter PNVs in the United States. This raises concern that there should be more regulation of PNVs.

A U.S. national survey reported that pregnant women are at risk of nutritional deficiencies in several key nutrients such as calcium, iron, folate, and vitamin D.¹ Adequate daily intake of certain key vitamins and minerals, collectively referred to as nutrients or micronutrients, are important to achieving a healthy pregnancy.¹ Inadequate intake of certain vitamins and nutrients has been associated with negative effects for both the neonate and the pregnant individual: folic acid deficiency has been associated with neural tube defects, severe maternal vitamin D deficiency can lead to maternal and fetal rickets disease, and iron deficiency is the most common cause of anemia in pregnancy.^2,3 Docosahexaenoic acid (DHA) has also been increasingly associated with improved brain development.⁴ Accordingly, the American College of Obstetricians and Gynecologists (ACOG) has published recommendations for daily amounts of key nutrients during pregnancy, which are also in accordance with recommendations from the Institute of Medicine Dietary Reference Intake.^5,6 Because it may be difficult to consistently obtain the recommended daily amounts from food intake alone, the ACOG recommends supplementation with a daily multivitamin during pregnancy.⁵ Specifically, the ACOG highlights the importance of taking a prenatal vitamin (PNV) with at least 400 μg of folic acid to reduce the incidence of neural tube defects.^2,5 However, studies show that despite approximately 78% of pregnant patients reporting using a PNV, many patients still do not achieve adequate nutritional intake of the recommended nutrients.^7-10

The U.S. Food and Drug Administration (FDA) currently classifies both prescription and nonprescription PNVs as dietary supplements, which means the FDA does not need to approve them for safety or effectiveness before they are marketed.¹¹ While there are certain mandatory labeling information requirements for certain ingredients, there are no regulations to ensure that these supplements contain specific amounts of any nutrients. As a result, there is wide variation in the formulation, content, and cost of individual PNVs, leaving it up to consumers and their healthcare providers to sort through the many options.¹² Many U.S. insurance plans also do not cover PNVs, so patients must choose from numerous over-the-counter products, which can be confusing and expensive.

Accordingly, it is important that both patients and providers understand the contents of common over-the-counter PNVs and how they compare with the ACOG recommendations for vitamin intake during pregnancy. Therefore, the aim of this study is to evaluate the reported amount of the ACOG-recommended nutrients in commercially available, over-the-counter PNVs in the United States, assess their adequacy compared with the ACOG guidelines, and to compare these supplements by cost. Five out of the 11 key nutrients (folic acid, iron, DHA vitamin D, and calcium) were specifically highlighted, as deficiencies in these five nutrients are known to correlate with significant clinical outcomes in pregnancy.^3-8,13,14

Materials and Methods

Product Selection

To assess the reported amounts of the recommended nutrients contained in each PNV, supplemental fact labels were examined through a convenience sample based on top searches for over-the-counter PNVs commercially available in the U.S. online. The first 30 online Amazon and Google Shopping items found using the keyword “prenatal vitamins” during the month of September 2022 were included for analysis if they included the words “prenatal” and “vitamin” in the label and contained multiple nutrients, excluding items marked as promoted ads. These online shopping forums were used because they are the largest global online shopping venue, as well as an aggregator of multiple shopping venues, respectively. Duplicate products between the two Web sites were merged.

Outcomes

The reported amounts of 11 key nutrients (folic acid, iron, DHA, vitamin D, calcium, choline, iodine, vitamin A, vitamin C, vitamin B6, and vitamin B12), as recommended by the ACOG, with ingredients converted to the same units as well as supplemental form (tablet, gummy, soft gel, etc.), and cost per 30-day supply for each product were recorded (Table 1).⁵ Then, a cost analysis of PNVs that met the ACOG recommendations for the highlighted nutrients compared with those that did not was done with a Wilcoxon rank sum test in Stata (StataCorp LLC, College Station, TX). Multiple linear regression was also performed to quantify the relationship between the 11 key nutrients and cost.

Table 1.

List of included over-the-counter prenatal vitamins sorted by name

No.		Cost/ month	Form	Folic acid	Iron	DHA	Vit D	Calcium	Choline	Iodine	Vit A	Vit C	Vit B6	Vit B12	kcal	Serving size
	Daily recommended amounta			400 μg	27 mg	200 mg	600 IU	1,000 mg	450 mg	220 μg	770 μg	85 mg	1.9 mg	2.6 mg
	Upper limitb			1,000 μg	45 mg	ND	2,000 IU	2,500 mg	3,500 mg	1,100 μg	3,000 μg	2,000 mg	100 mg	ND
	Product name
1	Actif Organic Prenatal Vitamin	14.12	Softgel	800	30	200	400	200	50	150	1,500	60	2.5	2.5		1
2	Alani Nu Prenatal	$34.99	Softgel	424	7.6	200	800	65	50	290	1,300	120	5	9.3		2
3	Alive! Prenatal Gummy	$11.66	Gummy	800	0	50	400	0	10	150	1,200	30	2.5	8	20	2
4	Best Nest Wellness Mama Bird Prenatal	$56.05	Caplet	480	18	0	400	64	50	150	1,200	100	4	6		1
5	Care/of Prenatal Multivitamins	$16.99	Tablet	360	18	0	1,000	225	250	150	190	20	1.9	2.6		3
6	CVS Brand Prenatal Vitamins	$3.54	Tablet	800	27	0	400	200	0	0	1,200	100	2.6	4		1
7	Enfamom Prenatal multivitamin	$18.99	Softgel	357	28	200	400	250	0	150	650	60	2.6	8		1
8	Eu Natural Conception Fertility Prenatal Vitamins	$31.49	Capsule	480	9	0	4,000	0	0	150	0	0	8.5	48		2
9	EVVOBODY Mama Essential Prenatal	$29.99	Capsule	360	27	0	800	50	55	290	1,305	65	18	9		2
10	Garden of Life myKind Organics Prenatal with folate and vitD	$31.08	Tablet	600	18	0	900	0	0	145	1,300	120	9	3		1
11	Garden of Life Vitamin Code “Raw Prenatal”	$19.92	Capsule	480	27	0	1,400	0	0	290	1,300	120	2	2.8		3
12	Horbaach women’s prenatal multivitamin	$2.33	Softgel	800	27	200	1,000	100	0	0	1,200	60	2.6	8		1
13	Love Wellness Baby Love	$10.00	Capsule	800	27	0	600	100	10	225	1,300	500	80	5.6		3
14	Lunakai Prenatal Supplement Gummies	$21.34	Gummy	480	2	0	333	0	0	0	300	33	1.6	10	15	2
15	MegaFood Baby & Me 2	$28.79	Capsule	0	0	250	0	0	160	0	0	0	0	0		2
16	Mommy’s Bliss prenatal multivitamin + iron	$12.66	Capsule	1,010	27	0	600	0	50	290	1,300	120	2	8	0	1
17	Mommy’s Bliss prenatal multivitamin + probiotics
18	Mommy’s Bliss Prenatal	$13.26	Capsule	600	27	0	600	0	50	290	1,300	120	2	8		1
19	Nature Made Prenatal	$5.50	Tablet	800	27	0	1,000	250	0	150	770	85	1.9	5.2		1
20	Nature Made Prenatal Gummies	$20.59	Gummy	360	0	58	1,000	130	55	150	650	25	2	5.2	30	2
21	Nature Made Prenatal, All-in-One Softgel	$9.13	Softgel	400	27	200	1,000	130	55	150	650	85	1.9	5.2	5	1
22	Nature’s Bounty Prenatal	$8.00	Softgel	800	28	200	400	175	0	150	1,200	100	2.6	8		1
23	Nature’s Bounty Prenatal Gummies	$32.93	Gummy	540	0	82.2	900	0	16.5	435	1,965	60	3	4.2		3
24	Nature’s Truth Prenatal	$3.45	Capsule	800	27	0	600	200	0	0	600	100	3	10		1
25	Needed Iron for Prenatal, Pregnancy, breastfeeding, postpartum	$10.00	Capsule	0	13.5	0	0	0	0	0	0	0	0	0		1
26	New Chapter Advanced Perfect Prenatal Vitamins	$30.29	Tablet	105	27	0	1,000	75	0	150	1,300	75	5	3		3
27	New Chapter Once Daily Age 35+	$22.49	Tablet	408	27	0	2,000	26	55	150	770	85	5	8.4		1
28	Nordic Naturals Prenatal DHA Soft Gels	$33.30	Softgel	0	0	480	400	0	0	0	0	0	0	0	10	2
29	Nutrigold Prenatal Multi Gold, Vegan Capsules	$30.37	Capsule	600	27	0	600	120	0	290	0	120	22	28		3
30	Olly The Essential Prenatal Folic Acid + DHA	$13.99	Gummy	400	0	40	800	0	10	150	650	30	2	3.5	30	2
31	Olly Ultra Strength Prenatal Multivitamin Softgels	$18.99	Softgel	600	7	200	800		68	150	650	60	2	6		2
32	One a Day Multivitamin, Complete, Advanced, Prenatal	$26.99	Softgel and tablet	800	27	200	600	150	110	150	650	85	2	2.8	5	1 Softgel + 1 tablet
33	One a Day Prenatal 1 with DHA Softgels	$15.76	Softgel	800	28	200	400	200	0	150	1,200	60	2.5	8	10	1
34	One a Day Prenatal Gummies	$28.35	Gummy	800	0	50	1,200	0	0	150	650	60	2	2.8	15	2
35	One a Day Women’s Prenatal 1 Multivitamin	$14.29	Softgel	Y	Y	Y	Y				Y	Y	Y	Y		1
36	Pink Stork Premium Prenatal Vitamin	$50	Capsule	360	27	200	600	195	0	290	1,300	120	2	2.8		2
37	Rae Wellness Prenatal Capsules	$14.99	Capsule	800	15	200	400	15	0	100	50	60	2	8	0	2
38	Rainbow Light Prenatal One	$8.99	Tablet	360	27	0	600	50	55	290	2,600	65	10	9		1
39	Revly Prenatal DHA + D3	$24.09	Softgel	0	0	450	800	0	0	0	0	0	0	0	10	2
40	Ritual Prenatal Multivitamin	$35	Capsule	600	18	350	2,000	0	55	150	0	0	0	8		2
41	Smarty Pants Prenatal Complete	$34.49	Gummy	800	0	41	1,000	0	12	150	900	60	2.5	7	50	6
42	Solimo Prenatal & DHA	$4.99	Softgel	360	0	50	800	0	0	220	650	20	2	2.8	20	2
43	Spring Valley Prenatal	$7.20	Gummy	800	0	50	400	0	10	0	1,200	30	2.5	8	20	2
44	The Honest Company—Love the Bump	18.99	Tablet	663	27	0	1,400	130	30	200	1,200	60	30	8	0	1
45	Theranatal One Prenatal Vitamin	$20.33	Softgel	500	27	300	3,000	0	0	220	0	15	1.9	2.6		1
46	Thorne Research Basic Prenatal	$26.10	Capsule	1020	45	0	1,000	180	0	150	1,050	150	12	200		3
47	Vitafusion Prenatal Gummy	$7.92	Gummy	360	0	50	800	0	0	220	650	20	2	2.8	25	2
48	Walgreens Prenatal Multivitamin Softgels	$15.99	Softgel	783	27	235	600	150	0	150	650	85	2	2.8		1
49	Walgreens Prenatal Vitamin	$2.37	Tablet	800	28	0	400	200	0	150	1,200	120	2.6	8		1
50	Zahler Prenatal Vitamin with DHA + Folate	$28.45	Softgel	600	27	300	2,000	100	55	290	650	60	4	100	10	2
	Total Compliant with Guidelines			35	26	18	34	0	0	14	25	19	42	43
	Percent Compliant with Guideline (n = 48)			72.9	54.	37.5	70.8	0	0	29.2	52.1	39.6	87.5	89.6

Abbreviation: ACOG, American College of Obstetricians and Gynecologists; ND, no data.

Notes: Each product also lists the following if the information was readily available: cost, form of vitamin, amount of eleven nutrients specified by the ACOG. Highlighted cells indicates that the nutrient meets daily requirements but does not exceed the upper limit of daily consumption.

^aPer the ACOG guidelines.²

^bPer national dietary references.¹⁴

Results

A total of 48 PNVs were included for final analysis. Of the initial 60 products found on Amazon and Google, 10 were duplicates, and 2 did not report nutritional values or specific values of each nutrient. The products included are listed in Table 1, along with the cost for 30-day supply, formulation, and amount of each of the 11 nutrients specifically recommended by the ACOG.

Of these PNVs, none were compliant with suggested amounts of all five of the prespecified key vitamins and nutrients (Fig. 1). No products met daily recommendations for calcium. Only five PNVs were compliant with recommendations with the other four key nutrients (Table 2). A total of 27.1% of PNVs did not have the recommended amount of folic acid (13/48). A total of 70.8% of PNVs had daily recommended amounts of vitamin D (34/48), but only 54.1% had the recommended amount of iron (26/48), and even fewer, 37.5%, had the recommended amount of DHA (18/48). Of note, no gummy vitamin had the recommended amount of iron or DHA (Fig. 1).

Fig. 1.

Prenatal vitamin formulation and compliance with the five pre-specified selected nutrients per the ACOG guidelines. Compliance defined as meeting or being above the daily recommended intake, but below national guidelines of the daily upper limit [2,12]. Combination (1) was a prenatal vitamin that was a combination of both softgel and tablet. ACOG, American College of Obstetricians and Gynecologists.

Table 2.

List of prenatal vitamin brands which supplemented four out of the five key vitamins or nutrients that were commonly found to be deficient per the U.S. National Survey and were recommended by the American College of Obstetricians and Gynecologists

Prenatal vitamin brands most adherent to the ACOG Nutrition Guidelines	Cost for 30-day supply (USD)
Horbaach Women’s Prenatal Multivitamin	$2.33
One A Day Multivitamin Complete Advanced Prenatal	$26.99
Nature Made Prenatal All-in-One Softgel	$9.13
Theranatal One Prenatal Vitamin	$20.33
Walgreen’s Prenatal Multivitamin Softgels	$15.99
Zahler Prenatal Vitamin with DHA + Folate	$28.45

Abbreviation: ACOG, American College of Obstetricians and Gynecologists.

Note: No studied brands, including these, sufficiently supplemented calcium.

In regard to price, PNVs ranged widely, from as low as $2.37/30-day supply to $56.05/30-day supply (Table 3). The median price of all PNVs was $18.99/30-day supply (interquartile range [IQR]: $9.99–$29.39). When comparing cost by formulation type, softgels had the lowest median cost at $17.49/30-day supply (IQR: $9.13–$24.09), and the most expensive form was a combination of a softgel and tablet PNV ($26.99/30-day supply), although there was only one such product. Gummy vitamins cost on average $20.59/30-day supply (IQR: $11.66–$28.35). The median cost of PNVs that were not compliant with the four nutrients mentioned above was $18.99/30-day supply (IQR: $10.00–$30.29), which was not statistically different from the median cost of the PNVs that did meet compliance with the four nutrients, which was $18.16/30-day supply (IQR: $9.13–$26.99, p = 0.55).

Table 3.

Average cost (median) of different forms of prenatal vitamins per 30-day supply

Form	Median cost in USD	IQR
Softgel (n = 14)	17.49	9.13–24.09
Tablet (n = 10)	17.99	5.5–30.29
Gummy (n = 9)	20.59	11.66–28.35
Capsule (n = 15)	23.01	12.66–30.37
Combination (n = 1)	26.99

Abbreviations: IQR, Interquartile range; USD, U.S. dollar.

When looking at the other six nutrients that make up the rest of the 11 nutrients that the ACOG recommends, choline was the most undersupplemented of the studied products, with 0/48 having adequate amounts. For the other nutrients, there was again variation in compliance across the PNVs (Table 4). Multiple linear regression of cost and the above 11 nutrients showed that there were no statistically significant associations of ingredients with cost, other than iodine amount (t = 2.11, p = 0.04).

Table 4.

Percent of prenatal vitamins in compliance with 11 key nutrients highlighted by the American College of Obstetricians and Gynecologists

Nutrient	Number of PNVs compliant N = 48	Percentage
Folic acida	35	72.9
Irona	26	54
DHAa	18	37.5
Vitamin Da	34	70.8
Calciuma	0	0
Iodine	14	29.2
Vitamin A	25	52.1
Vitamin B6	42	87.5
Vitamin B12	43	89.6
Vitamin C	18	37.5
Choline	0	0

Abbreviation: DHA, docosahexaenoic acid; PNV, prenatal vitamin.

^aOne of the five highlighted ingredients.

Discussion

Principal Findings

In this study, there were significant variations in the level of nutrients and cost of commercially available, over-the-counter PNVs in the United States. No PNV had adequate amounts of all five of the key nutrients of folic acid, iron, DHA, vitamin D, and calcium, and only 10.4% (5/48) PNVs had adequate amounts of four of these nutrients.

Results in Context of What Is Known

Our findings are consistent with previous studies regarding PNV supplementation that have shown that most products are not consistent with recommended nutrient levels.^12-14 One study comparing nutrient content and labeling in prescription versus nonprescription PNVs also showed that nutrient content and dosing was inconsistent across brands.¹² Another study done in Poland similarly found that most prenatal supplements did not follow recommendations regarding type and amounts of particular nutrients.¹³ Of note, in that study, only 55% of the PNVs contained the Polish Gynecological Society recommended amount of folic acid, and only 50% contained the recommended amount of vitamin D.¹³ A recently published paper in the United States also showed that among 421 vitamins analyzed, only one product contained target doses for six key nutrients.¹⁴ Of note, this product costed approximately $200/30-day supply and required seven tablets per daily serving.¹⁴

Interestingly, we found that cost did not correlate with PNV nutrient content, meaning spending more does not make patients more likely to obtain better products but supplement form did. For example, no gummy vitamin met the recommended daily requirement for DHA or iron, although they may be popular among patients who dislike or have difficulty ingesting tablets, capsules, or softgels. Also, tablets and softgels on average were the most cost-effective supplements. It is possible that this is because certain vitamins and minerals are more difficult to keep shelf-stable or be incorporated into gummy vitamins.¹⁵

Clinical Implications

Our findings that no PNV had adequate amounts of all five of the key nutrients of folic acid, iron, DHA, vitamin D, and calcium are particularly relevant in light of the 2015 U.S. Dietary Guidelines Advisory Committee findings, which showed that pregnant people had many shortfalls in nutrients, with 96% below the estimated average requirement (EAR) for iron, 90% below the EAR for vitamin D, 29% below the EAR for folate, and 24% below the EAR for calcium.¹⁶

The clinical importance of these five vitamins and nutrients in both the pregnant individual and the neonate have been validated in numerous studies.^2-4,17,18 Particularly alarming is our finding that more than 25% of PNVs studied did not meet the recommended amount of folic acid, which is known to be important in reducing the risk of fetal neural tube defects.² Iron deficiency can cause anemia of pregnancy, and, coupled with blood loss at the time of delivery, can increase the risk for maternal transfusion.^2,3 DHA is critical for fetal brain development and growth, and maternal DHA deficiency can affect behavioral changes in feeding, anxiety, and stress response even later in life.¹⁸ Maternal vitamin D is important for bone health in both the mother and fetus, as deficiency can lead to maternal and fetal rickets disease.² Finally, the World Health Organization recommends calcium supplementation in those with inadequate calcium intake, as low calcium may contribute to the development of preeclampsia, which affects approximately 1 in 25 pregnancies in the United States.¹⁷

While it is reasonable to assume that some of these nutrients will come from diet, the average daily intake for many of these nutrients in females ages 19 to 50 still fall far below the ACOG recommendations, and therefore, adequate supplementation from PNVs may be needed.¹⁹ Given these significant dietary shortfalls, it is especially important that PNVs provide patients with adequate supplementation of key nutrients during pregnancy. Our findings demonstrate the need for improved consistency of PNV contents to enable patients to achieve the ACOG recommended nutritional intake during pregnancy. Additionally, clinicians should be aware of the shortfalls of many PNVs and should work with their patients to encourage optimal nutrition in addition to PNV supplementation.

Furthermore, our findings are also important in the context of health equity. There are demographic and socioeconomic disparity in nutrition, where those in lower socioeconomic classes are more likely to have nutritional deficiencies.^20-23 Studies suggest that this is likely to be due diet quality as well as lack of nutritional knowledge.^21,22 Inconsistent nutrient contents of PNVs could further exacerbate nutritional disparities between those of different demographic and socioeconomic backgrounds. While PNV with adequate vitamin and nutrition may not address all nutritional needs in this population, it is possible that better adherence to the ACOG nutritional guidelines may alleviate some of these inequities.

Strengths and Limitations

The strengths of our study are that we address an important gap in the literature that is directly relevant to pregnant patients, patients seeking to become pregnant, and obstetric care providers across the United States. To our knowledge, this is the first such analysis of over-the-counter vitamins in the United States. Furthermore, we specifically incorporate the ACOG recommendations for 11 nutrients that are deemed most important in pregnancy, and we specifically review the nutritional contents by type, formulation, and cost.

Our study has limitations. First, it only incorporates findings from search engines such as Google and Amazon Shopping and does not include findings from physical stores. Therefore, selections may be different for individuals in different regions, and some of the PNVs included in this study may not be available to all. However, given the rise and accessibility of online shopping, they may represent a reasonable sampling of commercially available, over-the counter PNVs.²³ Another limitation is that we did not perform specific elemental ingredient analysis on these supplements and relied on the accuracy of supplemental labels. Other factors such as taste and patient tolerance to the supplement (i.e., if in gummy form) were also not accounted for.

Conclusion

Our study showed that there is significant variation in nutrient content and cost of over-the-counter PNVs. Strikingly, 27% of PNVs analyzed did not contain the ACOG recommended minimum amount of folic acid. Furthermore, none of the PNVs analyzed in this study contained adequate daily recommended amounts of the 11 nutrients recommended by the ACOG, and none of the gummy formulations contained adequate iron, DHA, or calcium. Moreover, increased cost is not correlated with increased consistency with the ACOG recommendations. Our findings suggest that more regulation and consistency of PNV contents is needed to help patients achieve the ACOG recommended nutritional intake during pregnancy and to enable both patients and providers to make informed decisions when choosing a PNV.

Key Points.

• Commercially available over the counter PNVs vary in their content of the ACOG recommended nutrients and vitamins for pregnancy.

• None of these studied PNVs contain adequate amounts of all five key nutrients.

• Cost is not correlated with more compliance with the ACOG recommendations.