Maternal nutrition is a cornerstone of public health, directly impacting the wellbeing of both mothers and their offspring. Optimal nutrition during pregnancy ensures proper fetal growth, reduces the risk of adverse birth outcomes, and contributes to the long-term health of both mother and child (1–3). Yet, micronutrient deficiencies remain widespread among pregnant women globally, particularly in low- and middle-income countries (LMICs) (4–6). Iron deficiency, a principal cause of anemia, affects up to 40% of pregnancies worldwide and is notably prevalent in South-East Asia (49%), Africa (46%), and the Eastern Mediterranean (41%) (3, 4, 7). Essential micronutrients such as folate, iron, calcium, vitamin D, and vitamin A are crucial during pregnancy, and deficiencies in these nutrients dramatically increase the risk of complications like maternal mortality, preeclampsia, low birth weight (LBW), preterm birth (PTB), small-for-gestational-age (SGA) infants, stunting, and even infant mortality (6, 8, 9).

In response to this global burden, the WHO and other health bodies recommend routine micronutrient supplementation, such as iron-folic acid (IFA) and, increasingly, multiple micronutrient supplements (MMS), to mitigate these risks (1, 4, 5, 10). Evidence underscores MMS as providing superior benefits to birth outcomes over IFA alone, with notable reductions in LBW, SGA, and neonatal deaths, particularly among undernourished and anemic pregnant women (5, 6). Nevertheless, the positive impacts of supplementation are heavily mediated by the degree of adherence among pregnant women. High adherence to supplementation protocols yields more favorable outcomes: for example, women who adhered to ≥90% of MMS showed a 56 g mean increase in birthweight compared to non-adherent peers, significantly lowering the incidence of adverse birth outcomes (4–6, 10). Despite the proven efficacy, real-world adherence rates to supplementation recommendations remain suboptimal. In some LMICs, only 8% of women who receive or purchase supplements actually consume the recommended dose, severely limiting program impact (11–13). In China, improving adherence has often been approached through general education or antenatal health education, yet these measures do not fully capture whether women can apply nutrition information in daily decisions and sustained supplement-taking (14). Maternal nutrition literacy (NL) represents this applied capacity and remains under examined in the Chinese prenatal context, particularly using pregnancy-specific validated instruments.

This gap in adherence is multifactorial, often rooted in issues of knowledge, accessibility, cultural beliefs, and health literacy (11, 15, 16). Maternal nutrition literacy (NL), the ability to obtain, understand, and apply information about nutrition, is increasingly recognized as a critical determinant of supplementation adherence (12, 13, 17). Nutrition literacy transcends factual knowledge (nutrition knowledge, NK), encompassing broader competencies such as interpreting food labels, critically evaluating sources of information, and enacting behavioral changes (4, 11). However, evidence remains limited in China regarding how pregnancy-specific NL, as a measurable construct distinct from education, relates to real-world micronutrient supplementation adherence during antenatal care. Deficits in maternal nutrition literacy are most pronounced among those with lower educational attainment, reduced financial resources, rural residence, and limited social support (18–20). For instance, higher education was consistently correlated with superior nutrition knowledge and literacy, while multiparity and family influence also positively impacted literacy levels (15, 18, 21). In contrast, limited NL is associated with poorer dietary diversity, later initiation of prenatal care, and increased risk of adverse pregnancy outcomes, including LBW, preterm birth, and stunting (10, 18, 22, 23).

Multiple studies show that nutrition literacy not only enhances dietary practices but also directly promotes behavioral adherence to recommended micronutrient supplementation. Women equipped with higher nutrition literacy are more likely to seek authoritative information, follow medical advice, and recognize the importance of continuous supplementation throughout pregnancy. Interventions aimed at improving maternal nutrition literacy, such as personalized counseling, health education, and community support, demonstrably increase supplementation compliance (10, 18, 24–26). Pregnant women receiving nutrition education are up to 2.8 times more likely to comply with iron-folic acid supplementation and experience greater increases in hemoglobin levels, directly translating to improved pregnancy and birth outcomes (25, 27–29). Moreover, community-based and participatory interventions that combine educational, social, and health system support can attain high compliance rates, frequently exceeding 75–90% in some populations (24, 30, 31).

Socio-demographic determinants, education, socioeconomic status, age, parity, rural vs. urban residence, employment, and the influence of media, collectively predict significant variance in maternal nutrition literacy and, hence, adherence (32–34). Higher family income increases access to health services and reliable information, whereas social support, particularly from partners and family members, enhances understanding and compliance (35, 36). Digital technology and mass media are emerging as important channels, with women possessing greater literacy utilizing internet-based resources more effectively and seeking out professional health advice (37, 38). Conversely, low nutrition literacy commonly results in inconsistent use of supplements, greater susceptibility to misinformation and myths, and diminished capacity to make informed decisions about maternal health (39, 40). Despite the recognized importance of NL, evidence from China is limited on how maternal nutrition literacy shapes adherence to prescribed prenatal micronutrient supplementation in routine antenatal care settings.

This study seeks to examine maternal nutrition literacy and its associated factors as determinants of micronutrient supplementation adherence among pregnant women, aiming to inform future public health interventions and maternal care policies. Our work provides empirical evidence from a large multi-center sample in China, addressing a critical knowledge gap regarding how maternal nutrition literacy shapes real-world adherence to micronutrient supplementation. By identifying both individual and contextual determinants of nutrition literacy and adherence, the findings offer actionable insights for designing targeted education, counseling, and health-system strategies. The results are expected to support policymakers and clinicians in strengthening prenatal nutrition programs and improving maternal and neonatal health outcomes.

This multi-center cross-sectional study investigated the status of maternal NL and its association with micronutrient supplementation adherence among pregnant women in China. Our findings reveal that while the majority of participants possessed “Good” nutrition literacy, a significant proportion (36.3%) demonstrated inadequate levels. The overall prevalence of adherence to prescribed micronutrients was 62.4%, indicating a substantial gap in optimal prenatal care. The most significant finding of this study is the robust, independent association between maternal NL and supplementation adherence. After adjusting for confounders, pregnant women with adequate NL were over three times more likely to adhere to their supplementation regimen compared to those with poor NL (AOR = 3.42), underscoring the critical role of health literacy in translating clinical recommendations into daily health behaviors.

Our mean NLAI-P score of 48.25 (63.5%) is slightly higher but comparable to the 46.59 reported by Zhou et al. (20) in the original development and validation of the NLAI-P, suggesting that maternal nutrition literacy (NL) levels in China have remained relatively stable or experienced modest improvement in recent years. Both our study and Zhou et al. (20) found a substantial proportion of pregnant women with inadequate NL, 36.3% in our sample vs. 40.9% in theirs, highlighting a persistent challenge despite ongoing national health initiatives. This enduring prevalence of low NL underscores that a significant demographic of pregnant women remains ill-equipped to process nutrition information, a finding echoed in other studies of Chinese women of reproductive age, which also report low nutrition knowledge and identify education, age, and urban residence as key determinants (41).

While our findings are consistent with Zhou et al. (20) regarding the distribution of NL levels, our slightly higher mean score may reflect incremental improvements, possibly due to increased public health efforts or greater access to nutrition information. However, the gap between knowledge and behavior remains a concern, as highlighted by Zhou et al. (20), who noted that while many women achieve moderate scores in knowledge, far fewer demonstrate adequate nutrition-related behaviors. This gap is further supported by broader literature, which finds that pregnant women often have some awareness of nutrition's importance but lack sufficient knowledge or practical skills to implement dietary recommendations, and that nutrition education from healthcare providers is often perceived as inadequate (29).

Our findings align closely with existing literature highlighting the persistent “knowledge-behavior gap” in maternal nutrition. Similar to our results, which revealed the highest scores in knowledge (68.0%) and the lowest in behavior (51.1%), prior studies have reported comparable discrepancies between awareness and practice. For instance, Rizkia et al. (42) observed that although pregnant women demonstrated adequate nutritional knowledge, behavioral adherence remained low, while Sangwan et al. (43) found that over 90% of women understood the need for additional food during pregnancy but only two-thirds acted on it. This reinforces the widely acknowledged notion that knowledge alone is insufficient to drive meaningful behavioral change during pregnancy. Importantly, this gap can be interpreted in relation to the intermediate performance of the Skill dimension (61.4%), which may represent the practical “translation capacity” required to convert nutrition knowledge into sustained behavior. In the NLAI-P framework, skills include nutrition decision-making and the ability to evaluate and apply information in daily life. In our cohort, common reasons for missed doses included fear of side effects (e.g., nausea/constipation) (28.3%) and perceiving supplements as unnecessary (11.5%), suggesting that the missing link is not awareness but actionable self-management skills (4, 44, 45). We hypothesize that key skills limiting adherence include: (1) managing and troubleshooting mild side effects and timing of intake, (2) interpreting personal need and benefits of supplementation across pregnancy stages, (3) planning routines and using cues or reminders to prevent forgetting, and (4) critically appraising online claims that may undermine confidence in supplementation (15, 45, 46). This may strengthen the rationale for interventions that move beyond knowledge provision toward skills-based, behaviorally anchored counseling.

The literature further attributes this gap to psychosocial and structural barriers that impede the translation of knowledge into practice. Jhaveri et al. (47) emphasized the roles of self-efficacy, family support, and resource availability in influencing dietary behavior, while Kavle (48) and Brink et al. (49) underscored the need for interventions that move beyond didactic education toward personalized, skills-based approaches. Thus, consistent with previous research, our results suggest that effective maternal nutrition interventions must target behavioral competence and environmental support systems to close the gap between “knowing” and “doing.”

The adherence rate of 62.4% reported in our study is consistent with recent evidence indicating moderate but suboptimal compliance with iron and folic acid supplementation among pregnant women. For instance, Tegodan et al. (50) found a nearly identical adherence rate of 62.3% among Ethiopian women, emphasizing that factors such as health literacy, exposure to nutritional counseling, and forgetfulness are critical determinants of supplement use. Similarly, studies in other regions have reported lower adherence levels, ranging from 40.9% in Adwa town Gebremichael and Welesamuel (51) to 51.4% among pastoralist women Boti et al. (52), demonstrating that adherence remains a global challenge. In China, available evidence suggests that guideline-concordant supplement use is often suboptimal, although operational definitions differ across studies. In a Beijing cohort, 97.2% of women reported taking folic acid supplements, yet only 24.2% were compliant with the recommended dose and duration, and even under a less stringent criterion the correct-use rate was 40.3%. In rural Shaanxi, only 44.5% of women reported periconceptional folic acid use despite relatively high pick-up rates (53). Taken together, our observed adherence rate of 62.4% (defined as taking ≥80% of prescribed doses over the past 30 days) may reflect a moderate level of adherence in an urban/suburban ANC population. However, direct comparisons across Chinese studies should be interpreted cautiously because of differences in supplements assessed and adherence definitions (30-day dose-taking vs. periconceptional “correct use”).

In contrast to earlier work that primarily emphasized formal education as a determinant of adherence Agegnehu et al. (54), our analysis identified nutrition literacy (NL) as a more potent predictor. This finding aligns with the emerging conceptual distinction between general education and applied health literacy, where NL reflects the ability to access, evaluate, and utilize nutritional information effectively. Studies such as Anato and Reshid (55) and Ramachandran et al. (56) support this notion, showing that targeted nutrition education significantly improves adherence and hemoglobin outcomes through enhanced comprehension and self-efficacy. Our results further demonstrate that women with higher NL may be better equipped to manage minor side effects, such as nausea, which accounted for 28.3% of non-adherence in our cohort, reflecting critical literacy and self-regulatory capacity. Together, these findings highlight the necessity of integrating nutrition literacy development into antenatal education to close the persistent gap between knowledge acquisition and behavioral adherence.

Our findings that women who relied primarily on healthcare providers (56.9%) exhibited higher adherence to supplementation than those depending on online sources are consistent with current literature emphasizing the enduring value of professional guidance in maternal nutrition. Multiple studies confirm that healthcare providers remain the most trusted and influential source of dietary advice during pregnancy. For instance, Gjestvang and Haakstad (57) found that although the Internet is widely used (up to 97%), healthcare professionals (HCPs) were consistently rated as the most reliable source of information and were associated with better adherence to nutritional guidelines. Similarly, Mitran et al. (34) demonstrated that advice from healthcare providers significantly improved diet quality and supplement adherence among women of reproductive age, underscoring the mediating role of professional counseling in shaping nutrition behaviors.

Conversely, reliance on digital and social media sources has been linked to confusion and misinformation. Recent evaluations of online pregnancy nutrition portals found considerable inconsistencies in supplement recommendations and poor alignment with official guidelines Skowrońska et al. (58). Similarly, qualitative research has shown that while pregnant women often turn to the internet due to convenience or lack of provider engagement, this self-directed information seeking can lead to anxiety and conflicting interpretations Snyder et al. (59). These findings support Zhou et al.'s (20) conceptualization of the “judgment of nutrition information” as a core skill within the Nutrition Literacy Assessment Instrument for Pregnant Women (NLAI-P), highlighting the importance of critical evaluation of information sources.

Nutrition knowledge among Chinese pregnant women is relatively higher than behavior, indicating that knowing recommended practices does not reliably translate into consistent supplement-taking. Improving pregnancy outcomes may therefore require interventions that move beyond information provision to strengthen functional and critical nutrition literacy, including practical skills for applying guidance and evaluating the reliability of digital nutrition information. Our findings can inform the design of targeted antenatal education programs and health system strategies to improve micronutrient supplementation adherence, particularly among women who are socioeconomically disadvantaged or who rely heavily on unverified online sources.