Scoping Review of Intervention Strategies for Improving Coverage and Uptake of Maternal Nutrition Services in Southeast Asia

Maternal undernutrition can lead to protein-energy malnutrition, micronutrient deficiencies, or anemia during pregnancy or after birth. It remains a major problem, despite evidence-based maternal-nutrition interventions happening on ground. We conducted a scoping review to understand different strategies and delivery mechanisms to improve maternal nutrition, as well as how interventions have improved coverage and uptake of services. An electronic search was conducted in PubMed and Google Scholar for published studies reporting on the effectiveness of maternal-nutrition interventions in terms of access or coverage, health outcomes, compliance, and barriers to intervention utilization. The search was limited to studies published within ten years before the initial search date, 8 November 2019; later, it was updated to 17 February 2021. Of 31 studies identified following screening and data extraction, 22 studies were included for narrative synthesis. Twelve studies were reported from India and eleven from Bangladesh, three from Nepal, two from both Pakistan and Thailand (Myanmar), and one from Indonesia. Nutrition education and counselling, home visits, directly observed supplement intake, community mobilization, food, and conditional cash transfer by community health workers were found to be effective. There is a need to incorporate diverse strategies, including various health education approaches, supplementation, as well as strengthening of community participation and the response of the health system in order to achieve impactful maternal nutrition programs.


Introduction
Maternal nutrition refers to increased nutritional demand during adolescence, antenatal, and postnatal periods. A shortfall in nutrition during these periods can lead to protein-energy malnutrition, micronutrient deficiencies, poor weight gain, or anemia [1]. In low-and middle-income countries, 450 million women are estimated to have short stature, 240 million are underweight (Body Mass Index-BMI < 18.5 kg/m 2 ), and 468 million are anemic [2]. This could be attributed, in part, to the poor performance of maternal nutrition programs in low-and middle-income countries. For example, only 31% of pregnant women in low-and middle-income countries consumed iron-folic acid tablets for 90+ days during pregnancy. Similarly, 19% of the population in Asia and 56% in Africa are food-insecure. Countries in Asia, like India and Bangladesh, and in Africa, like Ethiopia, Burkina Faso, Liberia, and South Sudan, etc., have some of the lowest coverage rates of one or more key interventions and practices addressing maternal and child malnutrition [3].
Maternal undernutrition is remarkably high in countries of South Asia, with Bangladesh reporting chronic energy deficiency among >30% of women of child-bearing age. Likewise,

Results
Search results: A total of 381 papers were identified from PubMed search, and eight from Google Scholar and reference snowballing. Of 381 papers, 315 were screened based on title and abstract ( Figure 1). After the titles and abstracts were reviewed, 231 articles were excluded. During full-text screening, of the remaining 84 articles, 53 articles were excluded, leaving 31 articles for data extraction and quality appraisal. Finally, 22 studies were included for narrative synthesis.

Quality Appraisal
An appraisal was conducted for all papers included after full-text screening. The quality of evidence of each article included in the review was assessed independently by two reviewers using the Joanna Briggs Institute quality-appraisal tool [16]. The overall quality was good, as most of the articles satisfied the criteria in the checklist (Supplementary Materials: Tables S1-S5). There was no disagreement between the two reviewers concerning the inclusion of papers based on the quality checks.

Quality Appraisal
An appraisal was conducted for all papers included after full-text screening. The quality of evidence of each article included in the review was assessed independently by two reviewers using the Joanna Briggs Institute quality-appraisal tool [16]. The overall quality was good, as most of the articles satisfied the criteria in the checklist (Supplementary Materials: Tables S1-S5). There was no disagreement between the two reviewers concerning the inclusion of papers based on the quality checks.

Characteristics of Included Articles
Of all the 31 studies included in the review, only 22 have at least one outcome associated with delivery mechanisms; the study characteristics of all the 31 papers are summarized in Tables 1 and 2  . A total of 22 studies were ultimately included in this review for narrative synthesis [17,18,[20][21][22][23][24][25][27][28][29][32][33][34]36,37,39,40,42,43,45,47]. Of these, twelve studies were RCTs, five were quasi-experimental trials, five were cross-sectional studies, three were mixed-method studies, three were secondary data analyses, one was a cohort study, and two were cross-sectional intervention/comparison studies. The majority (74%) of the studies was reported from India (12) and Bangladesh (11), three from Nepal, two from Pakistan (two others with India and Nepal), one from Indonesia, and two from Thailand (Myanmar). All identified studies were primarily quantitative, with a few studies reporting qualitative data as well. The intervention was delivered to 16802 households covering 3200 pregnant women, and there were 18659 households in the control area. The MNCH included awareness creation about positive maternal and newborn health care practices at the household level, such as the importance of seeking antenatal care, adequate nutrition during pregnancy and lactation, skilled birth attendance (antenatal care, early initiation of breastfeeding, delayed bathing, and recognition of danger signs that warrant early referrals), and practices promoted through community mobilization and education strategies that included formation of community health committees and group sessions using flip charts and videos. * NSI included intensive behavioral-change communication to promote appropriate complementary feeding practices, exclusive breastfeeding, establishment of kitchen gardens, and informing the community of their entitlements to subsidized food items through the state-modified public distribution system (PDS), which is a food-security program and is expected to supply a minimum food basket of cereals, sugar, and kerosene cooking fuel at a subsidized cost. Mitanin program included mitanin as counselors for families with either pregnant women or children under three years of age to improve coverage of maternal and child health services. ¶ MANOSHI is a community-based maternal, newborn, and child health care service package utilizing female CHWs (paid renumeration) to promote family-planning methods and provide door-to-door antenatal and postnatal care checkups to women. ** Intervention was conducted across 30 villages. Field-level program personnel included community service providers and community resource persons. Protagonists included persons who featured videos on mother and infant young-child nutrition. Key stakeholders included persons from partner organization. § Intensive maternal and newborn care services included formation of village-based maternal neonatal child health committees, training of traditional birth attendants on safe deliveriy, promotion of antenatal and postnatal care practices, tetanus toxoid injection, birth planning, counselling and communication strategy, adequate maternal nutrition, effective referral system, newborn care practices, complementary feeding, delayed bathing, and increased health-workers attendance at delivery.   WAZ: weight-for-age Z scores; WLZ: weight-for-length Z scores. ¶ Nutrition-focused MNCH included greater specificity of interpersonal counseling, provided free supplements, conducted weight-gain monitoring during pregnancy, engaged fathers more explicitly, and included community mobilization activities. α IFA-MNP: women who received iron and folic acid during pregnancy and the first 3 months postpartum, and children received micronutrient powder from 6-24 months of age; IFA-LNS: women received iron and folic acid during pregnancy and the first 3-months postpartum and children received lipid-based nutrient supplements from 6-24 months of age; LNS-LNS: women and children received lipid-based nutrient supplements; IFA-control: women who received iron folic acid supplements during pregnancy and the first 3 months postpartum, and children did not receive any supplements. * A PLA cycle had four phases: identify problem, plan strategies, act together, and evaluate impact; In the first phase, groups used participatory methods, such as picture cards, games, and stories, to discuss nutrition problems and local barriers to achieving good health during pregnancy. In the second phase, groups prioritized and voted on the issues they wanted to focus on, designed strategies to address these problems, and engaged the wider local community for support and feedback. In the third phase, the groups implemented these strategies while continually discussing new topics related to pregnancy and infant health. Finally, in the fourth phase, the groups reviewed what went well and discussed what to do next after the implementing organization withdrew from the community.

Summary of Interventions
These studies include interventions of micronutrient supplementation (IFA, Calcium, and multiple micronutrients), deworming, nutrition education and counseling, BEP supplementation, and delivery mechanisms for implementing these interventions. The strategies adopted in these reviews were home visits, directly observed supplement intake, community mobilization, food and cash transfer, community volunteers, and peer-group education. Almost all interventions used community health workers as the primary human resource for delivering interventions to beneficiaries. Nearly two thirds of the studies showed improvement in the uptake/coverage/compliance with the intervention or services. Tables S6 and S7 (Supplementary File) give an overview of the findings for each article included in the narrative synthesis. a.
Micronutrient supplementation (IFA, calcium, and multiple micronutrients) Community health workers, female health workers, research assistants, and community volunteers are crucial for delivery of nutrition supplements. Home visits, in particular, for delivering nutrition supplementation by various grassroots-level workers were also reported. IFA supplementation programs in Pakistan and Nepal were delivered by community health workers, and coverage of IFA supplements significantly increased in the last ten years, from 23% to 80% in Nepal. However, in Pakistan, coverage remained stagnant, at 45%. Analysis also recorded IFA consumption with respect to the number of antenatal care (ANC) visits in Pakistan. IFA consumption of 45% was recorded among those who had at least one ANC visit, compared to 9.7% with no ANC visit; hence, ANC visit is a critical factor in this intervention [22].
IFA supplementation delivered by trained female health workers through a fortnightly home visit and a quarterly community-based group session reported that the proportion of intake of supplements was >76%, which was quite good, considering 65% had irondeficiency anemia and low-birth-weight prevalence ranged from 18% to 40% [17]. An evaluation of the intervention package delivered through the trained community health workers and local health workers for improving perinatal and neonatal outcomes through community mobilization, education and home visits, use of information education and communication materials, videos, community health committees, and group meetings reported improved ANC services, including IFA and calcium supplementation [25].
Specially trained community health workers were reported to be the frontline facilitators delivering maternal nutrition services at the household, community, or facility level. MANOSHI, a community-based maternal, neonatal, and child health care service package among slum dwellers in Bangladesh delivered through female health workers through monthly home visits for IFA, calcium supplementation, and nutrition education, reported an increase in IFA consumption by 19% (p < 0.01) [28]. Similarly, the Government of Chhattisgarh, India, used community health workers, called mitanin (a local term for a close female friend), for improving the coverage of reproductive and child health services. Later, Nutrition Security Innovation, a project to inform families regarding their entitlement from the public distribution system, was integrated with this mitanin program to promote the appropriate complementary feeding through mitanins. An increased IFA consumption rate of 3% was reported, with a low occurrence of side effects [23].
Trained community health workers were recruited for delivery of ANC services, including nutrition-related services in Bangladesh through home visits or at community centers; their actions resulted in increased IFA consumption, with more than 82% of participants consuming more than 90 calcium tablets for more than three months. The study also reported a significant difference in the consumption of calcium tablets in relation to number of ANC visits; women who had four or more ANC checkups consumed more calcium tablets (p < 0.001) [39].
Directly observed consumption of supplements by the beneficiaries in the presence of community health workers was also associated with an increased consumption rate of multiple micronutrients (68%) and IFA (71%), indicating that successful distribution of supplements and direct observation of consumption of supplements improved adherence to consumption [18]. Additionally, a weekly home visit by community health workers to deliver micronutrient supplements was found to be associated with high compliance with supplements (median: 95, interquartile Range: 89.1, 98.4) [24]. Maternal nutrition knowledge and support from husbands were the key maternal and household factors associated with higher consumption of IFA and calcium tablets. Health service factors, like early and more prenatal care visits, ANC, and receipt of free supplements, also improved the consumption rate; for every home visit conducted by female health workers, four additional IFA and five additional calcium tablets were consumed by mothers. Combined exposure to these factors-knowledge, family support, and self-efficacy-was attributed to consumption of an additional 46 IFA and 53 calcium tablets, with 68% of pregnant women achieving minimum dietary diversity. Thus, regular home visits for delivery of micronutrient supplements at the doorsteps ensured that every pregnant woman received adequate supplementation [32]. Secondary analysis of an intervention study from India and Pakistan, where lipid-based micronutrient was provided through research assistants, showed a significant improvement in length-for-age Z-score (LAZ), weight-for-age Z-score, and reduction in low birth weight, as well as small-for-gestational-age incidence [47].

b. Nutrition education and counselling
Nutrition education and counselling provided by frontline health workers were informative and useful when provided by the mitanins in Chhattisgarh's mitanin program. It was reported that a significant number of households among the intervention group adopted kitchen gardening (46.6% vs. 32.5%), and more than 98% reported having received information on the importance of IFA consumption. Involvement of community volunteers in family-level counselling for behavioral change and for delivery of nutrition services was also effective, and monthly nutrition and health education provided by Anganwadi workers (community-based frontline workers who promote child growth and development) during home visits or during village health and nutrition days was associated with 35% increased coverage in delivery of pregnancy care and nutrition information [23,27,41]. Studies from India and Bangladesh on health and nutrition programs showed that the trained community health workers were crucial in imparting nutrition education and counselling in these countries and were reported to have significantly improved the calcium-supplement consumption rate [20,39]. Monthly home visits by community health workers in Bangladesh to deliver nutrition education interventions resulted in 73.3% of pregnant women reporting having had visits from community health workers, and nearly three-quarters of pregnant women could name at least five food groups that should be consumed daily. However, large knowledge-to-practice gaps were observed in terms of food consumption [32]. A similar study evaluated the effect of providing intensified nutrition-focused maternal, neonatal, and child health intervention compared to standard interventions. More than 96% of pregnant women in the intensified focused nutrition group received IFA and calcium tablets, and 40-50% of all mothers reported exposure to video shows. Proportion of IFA and calcium intake, number and quantity of food groups consumed, and daily intake of macronutrients improved substantially in the intensified focused nutrition group, as compared to the control group [33].
The participatory learning and action approach engages communities in learning and participation, identifying needs, planning, nutrition education, and counselling, and encouraging problem-solving. Studies were designed to assess the effects of pregnancyfocused nutrition interventions through the participatory learning and action approach, combined with the transfer of food or cash in intra-household food allocation, dietary adequacy, and maternal nutritional status in Nepal. Monthly group sessions were conducted in all the arms. The participatory approach used picture cards and stories for group discussions. A structured manual was prepared for nutrition mobilizers to conduct home visits and nutrition counselling to improve nutrition practice. The participatory learning and action approach with cash or food transfer reported a higher attendance rate at monthly meetings (80%) compared to the approach alone without cash or food transfer. The participatory learning and action approach with food transfer significantly improved the birth weight of the fetus and equity in energy allocation among pregnant women. It also improved dietary diversity and adequacy, as well as supplement consumption [37,40]. Conditional cash transfer of INR 5000 (Indian Rupee) delivered in four installments (1500 at end of second trimester, 1500 at third month after delivery, 1000 at the sixth month, and 1000 at the ninth month) was reported from India. Each installment was conditional on the uptake of certain health care services and outcomes. Compliance with conditions, such as consumption of IFA tablets; counselling during pregnancy; and the recommended immunization for bacillus Calmette-Guerin, polio, and diphtheria-pertussis-tetanus were observed to be significantly higher (unadjusted p < 0.01) among those receiving conditional cash transfer. Conditional cash transfer was also observed to be associated with an increased likelihood of pregnancy registration and receiving ANC services and IFA tablets from female health workers [34]. Counselling on maternal nutrition through home visits and participatory women's group meetings facilitated by community health workers at least twice a month was associated with a significant increase in the odds of pregnant women achieving minimum dietary diversity in intervention clusters (adjusted odds ratio 1.40; 95% CI 1.03 to 1.90, p = 0.0311) [36].
For the promotion of maternal, infant, and young-child nutrition, the components of behavior-change communication were integrated into agricultural extension programs on nutrition by developing cost-effective, video-based intervention. This showed that intake of IFA tablets was 86% among those who had received information, and several female health workers requested that the videos be disseminated during village health and nutrition days and during the monthly health and nutrition fairs. Female health workers also reported that the videos further helped in serving the community well. Interviews with various health workers, self-help groups, volunteers, and beneficiaries reported an increase in uptake and awareness of government services for improving nutrition [29]. c.
Balanced energy-protein supplementation Although evidence to evaluate potential long-term outcomes is not adequate, a few studies reported that supplementation of BEP diet in undernourished pregnant women facilitated gestational weight gain and improved fetal outcomes in terms of reducing the risk of stillbirth, low-birth-weight infants, and small-for-gestational-age babies. In Nepal, the provision of 10 kg per month of a fortified BEP supplement of wheat-soya blended flour with 10% added sugar, called super cereal, delivered by community health workers, along with the participatory learning and action approach, significantly improved the birth weight of newborns and equity in energy allocation among pregnant women [37,40]. Similarly, in Bangladesh, a locally produced food-based BEP supplementation for undernourished pregnant women delivered along with nutrition education and counselling and regularly monitored by community nutrition volunteers either at the designated center in the community or through home visits showed a 98% compliance rate, with almost all women consuming the full supplement daily [43]. However, evaluation of supplementary food programs delivered in India through the Integrated Child Development Service Scheme by Anganwadi workers reported that only 20.5% of women received supplementary food during their pregnancies due to a weak procurement system and poor quality of food products [20]. Another study from India and Pakistan provided additional protein-energy supplements to pregnant women whose BMI was <20 kg/m 2 only in the interventional groups. LAZ, weight-for-age z score, low birth weight, and small-for-gestational-age were much improved in the interventional groups as compared to the control group. Prevalence of newborn stunting (LAZ <−2) was 18% (Intervention 1: 10% & Intervention 2: 13%), wasting (weight-to-length ratio for age < −2) 42% (32% & 37%), preterm deliveries 12% (12% &8.5%), low birth weight 34% (28% & 29%) and small for gestational age 49% (36% & 44%) in the control group, as compared to the intervention groups [47]. d. Barriers affecting coverage, uptake, and compliance of program delivery Public health interventions are complex, and outcomes are unpredictable. Factors affecting the success of the programs are multidimensional. A few barriers to interventions were reported in some of the studies identified for this scoping review. An evaluation of the implementation of maternal nutrition programs in India reported that only 27.6% consumed at least 100 IFA tablets or syrup during their most recent pregnancy, only 4% took deworming medicine during pregnancy, 20.5% received supplementary food, and 10.9% received nutrition and health education. Similarly, the report recorded a meager utilization rate of the nutrition services provided at anganwadi centers and food-fortification projects implemented through the public distribution system. Inadequate and irregular supply of supplements, substandard quality of the food provided, misconceptions about intake of certain food items during pregnancy, and sharing of take-home rations with the household members were a few barriers that hindered program effectiveness [20]. Other factors that affected the delivery and uptake of interventions were resource shortages, socioenvironmental issues, including poverty, lack of awareness, and discrimination based on socioeconomic status in the community [21].
Certain policy-related barriers reported in different studies were low prioritization of maternal-nutrition intervention by policymakers and lack of proper thematic knowledge of the program reference. All these barriers were found to be associated with inefficient program management within the overall health system. One study also reported a low consumption rate of deworming pills (4%), despite receiving the targeted intervention, due to weak monitoring, evaluation, and not prioritizing time-bound targets [21]. Barriers to IFA consumption were reported to be a lack of appropriate need forecasting, delay in supply, inconsistent training on IFA counselling/distribution, low health literacy, unplanned pregnancy, no or late pregnancy registration, limited intervention resources, and misconceptions [42,45].

Discussion
This review is different from other reviews conducted on maternal-nutrition intervention in several ways. The objective of this review was not to identify evidence-based maternal-nutrition interventions but to document intervention strategies that have successfully improved coverage and uptake of maternal nutrition services and programs. Review of implementation of various evidence-based interventions to improve maternal nutrition and birth outcomes indicates that community health workers, home visits, directly observed nutrition supplementation, community mobilization, and social marketing approaches for delivery of interventions like IFA supplementation, deworming, BEP supplementation, and nutrition education and counselling provide better results in terms of coverage, compliance with services and uptake of these interventions. The present review qualitatively narrates various intervention strategies adopted to deliver programs to improve maternal nutrition and birth outcomes.

Effect of Home Visits by CHW on Compliance with Nutrition Interventions
Maternal nutrition status is crucial for fetal growth and development; nutrition supplements are effective in improving maternal and fetal outcomes and have been routinely administered to pregnant women [48][49][50]. The review found that auxiliary nurse midwives, female health workers, community health workers, Anganwadi workers, accredited social health activists, and community volunteers all play a crucial role in delivering public health interventions either at a designated facility or community centers, on a designated day or through house visits. Reported outcomes of various studies showed an increase in supplement consumption rate when nutrition services were delivered by community health workers through home visits [17,18,22,23]. These findings support other reviews reporting on the delivery of services through home visits by community health workers. Thus, by ensuring universal health care with strengthened primary health services, the prevalence of anemia and undernutrition could be reduced [6]. Sanghvi et al. 2016 [51] examined evidence of IFA supplementation and the effectiveness of intervention trials in a large-scale program and found that the active involvement of village health volunteers through home visits helps to improve compliance and ANC visits. Mason et al. 2012 [52] assessed the current scenario of IFA supplementation in India and reported that community health workers and auxiliary nurse midwives were the driving force for delivery of supplementation and observed an improvement in the uptake of services and intervention coverage. A recent population-based intervention study conducted by Edmond et al. (2018) [53] in Afghanistan evaluated the effectiveness of a program of home visits by trained community health workers and reported an increase in institutional delivery of 8.2% in the intervention group, as compared to 6.3% in the control group. There was also an increase in ANC visits of 3.4% in the intervention group, whereas a decline of 1% was observed in the control group. The findings show that home visits by community health workers improved care-seeking behavior and knowledge among pregnant women. Overall, home visits by community health workers increased coverage and compliance with the consumption of micronutrient supplements and uptake of ANC services.
Many studies lack data on the direct effect of health workers on the uptake of services/compliance (as revealed through association/regression/attribution) [12,18,19,23,24,26,29,[32][33][34][35]37,38,42,43]. These studies compared the effect of the intervention (as a whole) on the outcomes without delineating the isolated effects of health workers/delivery mechanisms. However, some studies reported on the impact of CHW on health outcomes. In the MANOSHI program, CHW/trained providers/medically trained providers who paid monthly antenatal and postnatal visits reported greater effect of CHW on improving the uptake of four or more ANC visits and quality ANC visits than the routine services [28]. Frontline workers, like ASHA/AWW who were of the same caste as the head of the household and were living in the same catchment area of pregnant women, had higher odds of providing immunization services to children under 5 years. and pregnancy-related counselling, respectively [27]. CHWs trained on additional curriculum of newborn care and with improved counselling skills enhanced maternal and newborn care practices significantly compared to those who did not receive additional training and skill development [25]. However, CHW visits in addition to existing AWW were not found to significantly affect child health outcomes [36].

Effects of Nutrition Education and Counselling on Compliance and Uptake of Nutrition Services or Intervention
Existing evidence suggests that nutrition education and counselling is an effective strategy, but the impact is more significant and substantial among undernourished populations of low-and middle-income countries when accompanied by nutritional services, like provision of free micronutrient supplements, ANC care, periodic reinforcements, and food supplementation [54,55]. Nutrition education and counselling is the primary responsibility of community health workers and auxiliary nurse midwives, and every nutrition intervention and program has a component of nutrition education and counselling either at the individual, household, community or facility level. Delivery of nutrition education by trained community health workers or female health workers was reported to be associated with good nutrition knowledge, greater support from the husband, higher consumption of supplements, and achievement of minimum dietary diversity [20,27,32,39]. Home-based counselling, group meetings, and community events provided by frontline workers were also reported to be informative and useful [41]. A review by Girard et al. 2012 [51] reported that nutrition education and counselling targeting maternal diet and supplement intakes during pregnancy helped to improve dietary patterns and adherence to a healthy diet. Studies have also reported that nutrition education and counselling increased compliance with micronutrient supplementation and uptake and utilization of ANC services, which is in line with the findings of the present study. Another review [56] reported that large-scale programs involving nutrition education and counselling usually delivered by community health workers and a program in Bangladesh on nutritional counselling for behavior change succeeded in creating awareness and attention towards undernutrition and in designing a sustainable nutrition program in the country. Similarly, a review by Vaivada et al. [57] reported that nutrition education and counselling for pregnant women in undernourished populations was effective in improving birth outcomes and home visits by specially trained community health workers for counselling and IFA supplement and facilitates decision making concerning IFA consumption [58].
Participatory learning and action (PLA) in combination with cash or food transfer led to higher attendance rates at monthly meetings, improved birth weight, and equity in energy allocation among pregnant women, while PLA with cash transfer improved adequate dietary diversity and supplement consumption [37,40]. Community interventions through home visits and PLA by local community-based workers significantly achieved adequate dietary diversity among pregnant women [36,42]. In concurrence with this rapid review, a non-RCT by Gope et al. 2019 [59] weighed the effects of two strategies concerning monthly PLA meetings with women's groups followed by home visits and crèches combined with monthly PLA meetings and home visits. Trained community health workers facilitated the implementation, and the study reported that 65-72% of mothers participated in the meetings, and an increase in the uptake of services, early initiation of breastfeeding, adequate dietary diversity among mothers, and consumption of iron-rich foods by children were recorded. PLA meetings, along with home visits, reduced undernutrition among children, suggesting the potential benefit of scaling up the intervention through accredited social health activists and their facilitators.

Effects of Food or Cash Transfer on Compliance and Uptake of Nutrition Services
Take-home rations and supply of fortified food through the public distribution system was one of the interventions used to address maternal undernutrition and low birth weight, [21] but a study from India revealed that 35% of the sample households received food supplements from Anganwadi workers and accredited social health activists, and only 20.5% women reported to have received supplementary food during their pregnancy through the integrated child development service scheme (ICDS) program [20,27]. Inversely, in Bangladesh, the delivery of locally produced prenatal food-based supplements to pregnant women led to a high compliance rate, with almost all participants consuming the full supplement on a daily basis [43]. Similarly, in Nepal, food and cash transfer with PLA led a high participation rate in program activities and significant improvement in birth weight of newborns, equity in energy allocation, and adequate dietary diversity [37,40]. Earlier reviews found conditional cash transfer to be a better intervention strategy than direct distribution of food supplements. Mexico and Brazil succeeded in conditional cash transfer programs, and this approach is now being endorsed and implemented in other low-and middle-income countries [54,56].
Another study from Mexico [60] on the nutritional impact of a large-scale, incentivebased development program (PROGRESA), which includes the provision of micronutrient fortified food supplements to eligible women and cash transfers of USD 25 per family, with the condition of complying with specific healthcare appointments, including a mandatory session on nutrition and health education, showed an overall improvement in the consumption of nutrient supplements, improvement in height, and reduction in anemic cases. This indicates the potential benefit of the program for improving adherence to the intervention.
In India, the Janani Suraksha Yojana (JSY) program provided cash benefits to pregnant women from low-income households to promote institutional delivery, which led to an increase in the utilization of ANC and skilled delivery. This, in turn, led to a decline in perinatal mortality. Conversely, the provision of conditional monthly food rations and micronutrient-fortified individual rations for daily consumption improved the participation rate by more than 95% for monthly group sessions. High attendance and participation rates indicate that delivery of targeted nutrition intervention through conditional food ration facilitates program effectiveness in achieving its desired outcomes [61,62].

Effect of Community-Level Events, Social Marketing Campaigns or Group Sessions on Compliance and Uptake of Nutrition Services
Village health and nutrition day (VHND) in India, maternal and child health weeks in Nigeria, and enhanced outreach strategies or community health days in Ethiopia are examples of campaign-based approaches for delivery of nutrition interventions. VHND, a monthly event usually organized at Anganwadi centers, provides nutritional services, such as nutrition education and counselling and fortified take-home food rations to pregnant women, lactating mothers, and children. In Ethiopia and Nigeria, pregnant women and lactating mothers are screened to determine targeted beneficiaries for food supplementation through health days or health-week campaigns, as the majority of the women is reported to miss ANC visits [54]. Similarly, several reports in this review also discussed social campaigns, community events, or designated days for delivery of interventions. VHND is a beneficial platform for reaching those who did not receive services through other platforms, utilization of information, education and communication materials for conducting community group meetings, home-based sessions for delivery of nutrition education messages, delivery of supplements and problem-solving through peer group discussions, etc. [20,25,42].
Community-level campaigns were found to be effective in creating awareness and promoting the intake of supplements. Social marketing and community-based education sessions using information, education, and communication material before distribution of supplements were found to be effective in the uptake and usage of supplements [19]. Similar interventions reported that the involvement of community health workers in community mobilization activities and home visits helps in tracking uptake and utilization of nutritional services and identifying defaulters [63]. A study from Africa reported an increase in the utilization rate of healthcare-related services following intensive and exhaustive community-mobilization and advocacy activities [64]. Similarly, a study from Vietnam promoting IFA consumption reported community mobilization and social marketing as an effective intervention strategy for promotion of uptake of services and intervention coverage. The study also reported a significant change in the knowledge, attitude, and practice of the targeted beneficiaries related to health and nutrition [65].

Strengths and Limitations
We have identified a wider range of maternal nutrition programs and their implementation through a stringent process to include them in this review. However, only PubMed and Google Scholar were searched to identify articles, as there was a lack of time and resources. Owing to this, there could be a greater chance of missing out on other relevant studies not indexed in PubMed or Google Scholar. Additionally, meta-analysis was not performed in the present paper due to varied outcome indicators and non-uniformity in the presentation of results across studies. However, the studies included in the review present a diverse range of strategies to improve maternal nutrition in many countries, including India, Pakistan, Indonesia, etc., compared to the previous reviews. Furthermore, many aspects of maternal nutrition programs were discussed, including strategies, effectiveness to improve maternal and child health outcomes, and delivery mechanisms. This makes this paper relevant for policy makers, public health specialists, and academicians.

Conclusions
Specific interventions targeting maternal nutrition have proven to be effective in improving pregnancy outcomes. However, the proportion of people who benefitted from these interventions in South-East Asian countries, with a high prevalence of anemia and underweight women and low rates of IFA consumption, [66] needs to be explored. Implementing public health programs, small or large, is complex and requires an understanding of cultural diversity, the public health system, and population characteristics, and program implementers should examine the benefits of effective intervention strategies for context-specific and effective program design.
In this review, intervention strategies, such as home visits, nutrition education, and counselling through different means, including video-based sessions, free supplementation of IFA/calcium tablets, monitoring of ANC visits, and community mobilization and meetings, were found to be associated with higher intervention coverage, increased compliance with intervention, and uptake of services. However, intervention strategies such as food rations and food transfer showed varied effects. Studies from India reported that the quality of food supplied under food-transfer programs was not suitable for consumption, which inversely affected program coverage. Cash transfer, on the other hand, led to improved compliance with interventions, as reported by studies from Nepal, although evidence was not definitive and needs further evaluation.
The overall findings from this scoping review were that strengthening of ANC at the community or facility level to promote ANC visits, frequent home visits, building capacity of community health workers, promoting participatory community mobilization, nutrition campaigns, conditional cash transfer, provision of food supplements, and improving quality of food supplements improve coverage, compliance, and uptake of services. Furthermore, there is a need to improve quality and regular supply and address the shortage of food supplements, with continuous monitoring. Solutions to address barriers related to program delivery are needed to further improve effectiveness. Besides, the socioenvironmental factors such as poverty, lack of awareness, and misconceptions in the community require immediate action. The findings of this review will help decision makers and program implementers who seek to understand the complexity of implementing such evidencebased interventions addressing maternal undernutrition and birth outcomes for effective program design and improvement of program efficiency and effectiveness.