A randomized trial evaluating the effect of 2 regimens of maternal vitamin a supplementation on breast milk retinol levels

Nutritional Status of Breastfeeding Mothers and Impact of Diet and Dietary Supplementation: A Narrative Review

Adequate nutrition during breastfeeding is crucial for ensuring the good health of mothers and babies. Despite the high energy and nutrient demands of breastfeeding, lactating women are often vulnerable from a nutritional perspective. The nutritional focus during breastfeeding tends to be on the newborn, often neglecting the mother's diet. Therefore, in the present narrative review, nutrient intakes were compared with the dietary reference values (DRVs) proposed by the European Food Safety Authority (EFSA) as well as by the World Health Organization/Food and Agriculture Organization (WHO/FAO). In the diets of lactating mothers, dietary inadequacies were observed in the intake of some vitamins, such as folic acid, vitamin B12, vitamin A, and vitamin D, and in the intake of certain minerals like calcium, iron, and iodine; polyunsaturated omega-3 fatty acid deficiencies, primarily in eicosapentaenoic acid and docosahexaenoic acid, were also observed. On the other hand, the debate on the necessity of supplementation during lactation continues; the need for nutritional supplementation during lactation depends on many factors, such us mothers' eating habits. There seems to be a positive association between nutritional supplementation of the lactating mother and the concentration of certain nutrients in human milk. The present narrative review provides an update on the nutritional status (fatty acids and micronutrients) of breastfeeding mothers and the impact of diet and dietary supplementation on human milk composition.

Vitamin A Concentration in Human Milk: A Meta-Analysis

Humans require vitamin A (VA). However, pooled VA data in human milk is uncommon internationally and offers little support for dietary reference intake (DRIs) revision of infants under 6 months. As a result, we conducted a literature review and a meta-analysis to study VA concentration in breast milk throughout lactation across seven databases by August 2021. Observational or intervention studies involving nursing mothers between the ages of 18 and 45, with no recognized health concerns and who had full-term infants under 48 months were included. Studies in which retinol concentration was expressed as a mass concentration on a volume basis and determined using high-, ultra-, or ultra-fast performance liquid chromatography (HPLC, UPLC, or UFLC) were chosen. Finally, 76 papers involving 9171 samples published between 1985 and 2021 qualified for quantitative synthesis. Results from the random-effects model showed that the VA concentration of healthy term human milk decreased significantly as lactation progressed. VA (µg/L) with 95% CI at the colostrum, transitional, early mature and late mature stages being 920.7 (744.5, 1095.8), 523.7 (313.7, 733.6), 402.4 (342.5, 462.3) and 254.7 (223.7, 285.7), respectively (X2 = 71.36, p < 0.01). Subgroup analysis revealed no significant differences identified in VA concentration (µg/L) between Chinese and non-Chinese samples at each stage, being 1039.1 vs. 895.8 (p = 0.64), 505.7 vs. 542.2(p = 0.88), 408.4 vs. 401.2 (p = 0.92), 240.0 vs. 259.3 (p = 0.41). The findings have significant implications for the revision of DRIs for infants under six months.

Breast Milk Retinol Levels after Vitamin A Supplementation at Different Postpartum Amounts and Intervals

Maternal vitamin A (VA) supplementation in risk areas for Vitamin A deficiency (VAD) was launched to improve the level of this nutrient in nursing mothers and in their breast milk. This longitudinal and randomized study aimed to evaluate the levels of retinol in breast milk after supplementation with VA in varying amounts (200,000 IU or 400,000 IU) and different postpartum intervals. Women were distributed into four intervention groups and given a single 200,000 IU postnatal dosage of VA at time 0 h (postnatal morning) (G200 0H); a single 200,000 IU dosage of VA in week four (G200 4W); 200,000 IU of VA at time 0 h + 200,000 IU of VA 24 h after the first supplementation (G400 24H); and 200,000 IU of VA at time 0 h + 200,000 IU of VA one week after the first supplementation (G400 1W). Breast milk samples were collected over a 12-week period (0 h, 24 h and 1, 4, 12 weeks post-natal). Retinol levels were determined by high-performance liquid chromatography. The Generalized Estimated Equation (GEE) assessed the different retinol levels. The G200 (0H), G400 (24H), and G400 (1W) groups presented higher retinol levels at 24 h than the G200 (4W) group (p < 0.001). The retinol levels of all groups were similar at times 1, 4 and 12 weeks after delivery (p > 0.05). Maternal VA supplementation increased retinol levels in the colostrum. Different supplementation dosages or postpartum administration times did not result in added benefit to retinol levels in mature breast milk.

Effect of Vitamin A Supplementation, Cooking Oil Fortification, and Nutrition Education to Postpartum Mother on Breast Milk Retinol Levels

AIM: The study aims to determine the effect of two forms of Vitamin A supplementation (dose of 2 × 200 000 IU and dose of 1 × 200 000 IU), Vitamin A fortified cooking oil and nutritional education on retinol levels of breast milk. METHODS: A quasi-experiment design was used in this study with a total of 129 subjects divided into four groups; Group A (given 2 capsule of Vitamin A), Group B (given 1 capsule of Vitamin A), Group C (given cooking oil fortification), and Group D (given nutritional education). Retinol levels of the breast milk were measured 3 times (before, during, and after intervention). RESULTS: There were no differences in subject characteristics in terms of age, education, occupation, parity, and nutritional status between intervention groups (p > 0.05). The average of breast milk retinol levels was 52.15 μg/dl at the beginning. At the end of the measurement, the average decrease in breast milk retinol levels was higher in Group D (−27.2 μg/dl), and the lowest was in Group C (−9.9 μg/dl). The results of statistical tests showed that there was no difference in breast milk retinol levels between intervention groups in before, during, and after the intervention (p > 0.05). CONCLUSIONS: Fortified cooking oil and Vitamin A supplementation (1 × 200 000 IU) tend to maintain normal levels of retinol in breast milk compared to Vitamin A supplementation (2 × 200 000 IU) and nutrition education.

Small-Quantity Lipid-Based Nutrient Supplements Do Not Affect Plasma or Milk Retinol Concentrations Among Malawian Mothers, or Plasma Retinol Concentrations among Young Malawian or Ghanaian Children in Two Randomized Trials

BACKGROUND

Vitamin A (VA) deficiency is prevalent in preschool-aged children in sub-Saharan Africa.

OBJECTIVES

We assessed the effect of small-quantity lipid-based nutrient supplements (SQ-LNS) given to women during pregnancy and lactation and their children from 6 to 18 mo of age on women's plasma and milk retinol concentrations in Malawi, and children's plasma retinol concentration in Malawi and Ghana.

METHODS

Pregnant women (≤20 wk of gestation) were randomized to receive daily: 1) iron and folic acid (IFA) during pregnancy only; 2) multiple micronutrients (MMN; 800 μg retinol equivalent (RE)/capsule), or 3) SQ-LNS (800 μg RE/20g) during pregnancy and the first 6 mo postpartum. Children of mothers in the SQ-LNS group received SQ-LNS (400 μg RE/20 g) from 6 to 18 mo of age; children of mothers in the IFA and MMN groups received no supplement. Plasma retinol was measured in mothers at ≤20 and 36 wk of gestation and 6 mo postpartum, and in children at 6 and 18 mo of age. Milk retinol was measured at 6 mo postpartum. VA status indicators were compared by group.

RESULTS

Among Malawian mothers, geometric mean (95% CI) plasma retinol concentrations at 36 wk of gestation and 6 mo postpartum were 0.97 μmol/L (0.94, 1.01 μmol/L) and 1.35 μmol/L (1.31, 1.39 μmol/L), respectively; geometric mean (95% CI) milk retinol concentration at 6 mo postpartum was 1.04 μmol/L (0.97, 1.13 μmol/L); results did not differ by intervention group. Geometric mean (95% CI) plasma retinol concentrations for Malawian children at 6 and 18 mo of age were 0.78 μmol/L (0.75, 0.81 μmol/L) and 0.81 μmol/L (0.78, 0.85 μmol/L), respectively, and for Ghanaian children they were 0.85 μmol/L (0.82, 0.88 μmol/L) and 0.88 μmol/L (0.85, 0.91 μmol/L), respectively; results did not differ by intervention group in either setting.

CONCLUSIONS

SQ-LNS had no effect on VA status of mothers or children, possibly because of low responsiveness of the VA status indicators.

Nutritional supplements and mother's milk composition: a systematic review of interventional studies

Background

This study aims to systematically review the effects of maternal vitamin and/or mineral supplementation on the content of breast milk.

Methods

We systematically searched electronic databases including Medline via PubMed, Scopus and ISI Web of Science till May 24, 2018. The following terms were used systematically in all mentioned databases: (“human milk” OR “breast milk” OR “breast milk composition” OR “human breast milk composition” OR “composition breast milk” OR “mother milk” OR “human breast milk” OR “maternal milk”) AND (“vitamin a” OR “retinol” OR “retinal” OR “retinoic acid” OR “beta-carotene” OR “beta carotene” OR “ascorbic acid” OR “l-ascorbic acid” OR “l ascorbic acid” OR “vitamin c” OR “vitamin d” OR “cholecalciferol” OR “ergocalciferol” OR “calciferol” OR “vitamin e” OR “tocopherol” OR “tocotrienol” OR “alpha-tocopherol” OR “alpha tocopherol” OR “α-tocopherol” OR “α tocopherol” OR “vitamin k” OR “vitamin b” OR “vitamin b complex” OR “zinc” OR “iron” OR “copper” Or “selenium” OR “manganese” OR “magnesium”) and we searched Medline via Medical subject Headings (MeSH) terms. We searched Google Scholar for to increase the sensitivity of our search. The search was conducted on human studies, but it was not limited to the title and abstract. Methodological quality and risk of bias of included studies were evaluated by Jadad scale and Cochrane risk of bias tools, respectively.

Results

This review included papers on three minerals (zinc, iron, selenium) and 6 vitamins (vitamin A, B, D, C, E and K) in addition to multi-vitamin supplements. Although studies had different designs, e.g. not using random allocation and/or blinding, our findings suggest that maternal use of some dietary supplements, including vitamin A, D, vitamin B1, B2 and vitamin C might be reflected in human milk. Vitamin supplements had agreater effect on breast milk composition compared to minerals. Higher doses of supplements showed higher effects and they were reflected more in colostrum than in the mature milk.

Conclusion

Maternal dietary vitamin and/or mineral supplementation, particularly fat- soluble vitamins, vitamin B1, B2 and C might be reflected in the breast milk composition. No difference was found between mega dose and single dose administration of minerals.

Efect of vitamin A suplementation: a systematic review

To evaluate the effect of vitamin A supplementation in postpartum infants and women on serum retinol levels and breast milk. The databases Medline, PubMed, Lilacs and SciELO were consulted. The descriptors used were vitamin A, dietary supplement, child, postpartum period, infant and nutrition programs policies. Search found 7432 articles. After elimination of duplicity and application of eligibility criteria, 8 studies remained. All evaluated the effect of vitamin A supplementation on immediate postpartum, five studies used retinyl palmitate supplementation, one with retinyl palmitate and two did not specify the form of supplementation. Six studies evaluated colostrum and two included supplementation of children. It was found that supplementation in the puerperium increases the concentrations of serum retinol and breast milk, however, this result was in the short term and was relevant when the previous concentrations of the mother were low. When maternal serum concentrations are adequate, the retinol content in milk does not change, with little relevance for children. Further studies should be performed to evaluate the effect of megadoses supplementation on serum concentrations of children.

Retinol-to-Fat Ratio and Retinol Concentration in Human Milk Show Similar Time Trends and Associations with Maternal Factors at the Population Level: A Systematic Review and Meta-Analysis

Vitamin A in human milk is critical for meeting infant requirements and building liver stores needed after weaning. A number of studies have measured milk retinol, but only a subset have corrected for fat, which serves as the retinol carrier in breast milk. The purpose of the present work was to review and analyze studies in which human-milk retinol concentrations were reported in relation to milk fat and to compare these results with unadjusted breast-milk retinol concentrations in terms of time trends over the course of lactation, influences of maternal nutritional and constitutional factors, and effects of maternal vitamin A supplementation. A systematic approach was used to search the available literature by using the US National Library of Medicine's MEDLINE/PubMed bibliographic search engine. Observational and intervention studies were included if the research was original and the retinol-to-fat ratio (retinol:fat) in human milk was measured at ≥1 time point during the first 12 mo of lactation. Retinol:fat and retinol were highest in colostrum, declined rapidly in early lactation, and achieved statistical stability by 2 and 4 wk lactation, respectively. In mature milk, retinol concentration was positively correlated with milk fat (r = 0.61, P = 0.008). Breast-milk retinol:fat and retinol were positively associated with maternal vitamin A intake but were associated with plasma retinol only when dietary intake was inadequate. Postpartum supplementation with high-dose vitamin A (200,000-400,000 IU) resulted in significantly higher breast-milk retinol:fat for 3 mo and retinol for 6 mo (P < 0.05). In populations, the 2 indexes show similar trends and associations with maternal factors. Future studies should monitor how the uptake of retinol into the mammary gland affects maternal vitamin reserves, particularly in women who are at risk of vitamin A deficiency.

Vitamin A nutritional status in high- and low-income postpartum women and its effect on colostrum and the requirements of the term newborn

OBJECTIVE

To evaluate the vitamin A status in serum and colostrum of postpartum women with different socioeconomic status, comparing the colostrum retinol supply with the vitamin A requirement of the newborn.

METHODS

Cross-sectional study conducted with 424 postpartum women. Vitamin A maternal dietary intake was estimated using a food frequency questionnaire. Colostrum and serum retinol levels were measured by high performance liquid chromatography (HPLC). Serum retinol concentrations <20μg/dL were indicative of vitamin A deficiency (VAD). Vitamin A levels provided by colostrum <400μgRAE/day were considered as insufficient for term newborns.

RESULTS

The mean maternal vitamin A intake during pregnancy was 872.2±639.2μgRAE/day in low-income women and 1169.2±695.2μgRAE/day for high-income women (p<0.005). The prevalence of vitamin A deficiency was 6.9% (n=18) in the low-income group and 3.7% (n=6) in the high-income group. The estimated mean retinol intake by infants of the high- and low-income mothers were 343.3μgRAE/day (85.8% AI) and 427.2μgRAE/day (106.8% AI), respectively.

CONCLUSIONS

Serum vitamin A deficiency was considered a mild public health problem in both populations; however, newborns of low-income women were more likely to receive lower retinol levels through colostrum when compared with newborns of high-income mothers.

Vitamin A supplementation in Brazilian pregnant and postpartum women: a systematic review

OBJECTIVE

To assess the impact of vitamin A supplementation on adult pregnant and puerperal women in Brazil regarding the content of vitamin A and secretory immunoglobulin A on colostrum and breast milk, in child's health conditions, and in mother-child binomial vitamin A status.

METHODS

A research was conducted in Medline, Scopus, Web of Science, and Lilacs electronic databases for the studies published between January 2000 and January 2014. The methodological quality of the studies was assessed according to Jadad scale. The study search was conducted in January 2014, independently by two authors.

RESULTS

Seven studies were found concerning the effects of vitamin A supplementation in the puerperal period on breast milk and infant morbidity. No study regarding pregnant women supplementation was found. The supplementation in the puerperal period raised the retinol content on breast milk, thus increasing the offer of vitamin A for the child and the concentration of secretory immunoglobulin A on colostrum. There was no description of effects on infant morbidity.

CONCLUSION

It seems that the advantages of postpartum supplementation were not established in the Brazilian program, although the supplementation contributes to a better nutritional status of vitamin A for both the child and the puerperal woman and increases the offer of vitamin A for the newborn through the breast milk.

Breast milk retinol concentration in mothers of preterm newborns

BACKGROUND

Preterm newborns have low vitamin A reserves at birth, which increases their risk of morbidity and mortality. In the absence of supplementation, breast milk is the only source of this nutrient for exclusively breastfed infants.

AIMS

To assess retinol concentration in preterm milk and the relationship between this retinol concentration and lactation phase, degree of prematurity, and maternal serum retinol level.

STUDY DESIGN

Longitudinal study.

SUBJECTS

Fifty-eight preterm mothers.

OUTCOME MEASURES

Colostrum (1-3d), transitional (7-15d), and mature human milk (30-55d) samples were collected. Maternal blood was collected once at postpartum. Retinol level was measured using high-performance liquid chromatography.

RESULTS

Milk retinol concentration was statistically different between lactation phases (p<0.001): 2.84±1.05μmol/L in colostrum (58), 3.47±1.28μmol/L in transitional (58), and 2.03±0.61μmol/L in mature milk (30). No difference was found in milk retinol levels between groups with different degrees of prematurity (p>0.05). Maternal serum retinol (1.82±0.50μmol/L) did not correlate with milk levels (p>0.05).

CONCLUSIONS

Retinol level in preterm milk seems to be independent of the degree of prematurity and maternal serum status. A significant increase in micronutrient levels in transitional milk was observed, which is likely to contribute to reserves in the premature liver.

Vitamin A supplementation for postpartum women

BACKGROUND

In areas where vitamin A deficiency (VAD) is a public health concern, the maternal dietary intake of vitamin A may be not sufficient to meet either the maternal nutritional requirements, or those of the breastfed infant, due the low retinol concentrations in breast milk.

OBJECTIVES

To evaluate the effects of vitamin A supplementation for postpartum women on maternal and infant health.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (8 February 2016), LILACS (1982 to December 2015), Web of Science (1945 to December 2015), and the reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or cluster-randomised trials that assessed the effects of vitamin A supplementation for postpartum women on maternal and infant health (morbidity, mortality and vitamin A nutritional status).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, conducted data extraction, assessed risk of bias and checked for accuracy. We assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

Fourteen trials of mainly low or unclear risk of bias, enrolling 25,758 women and infant pairs were included. The supplementation schemes included high, single or double doses of vitamin A (200,000 to 400,000 internation units (IU)), or 7.8 mg daily beta-carotene compared with placebo, no treatment, other (iron); or higher (400,000 IU) versus lower dose (200,000 IU). In all trials, a considerable proportion of infants were at least partially breastfed until six months. Supplement (vitamin A as retinyl, water-miscible or beta-carotene) 200,000 to 400,000 IU versus control (placebo or no treatment) Maternal: We did not find evidence that vitamin A supplementation reduced maternal mortality at 12 months (hazard ratio (HR) 1.01, 95% confidence interval (CI) 0.44 to 2.21; 8577 participants; 1 RCT, moderate-quality evidence). Effects were less certain at six months (risk ratio (RR) 0.50, 95% CI 0.09 to 2.71; 564 participants; 1 RCT; low-quality evidence). The effect on maternal morbidity (diarrhoea, respiratory infections, fever) was uncertain because the quality of evidence was very low (50 participants, 1 RCT). We found insufficient evidence that vitamin A increases abdominal pain (RR 1.28, 95% CI 0.95 to 1.73; 786 participants; 1 RCT; low-quality evidence). We found low-quality evidence that vitamin A supplementation increased breast milk retinol concentrations by 0.20 µmol/L at three to three and a half months (mean difference (MD) 0.20 µmol/L, 95% CI 0.08 to 0.31; 837 participants; 6 RCTs). Infant: We did not find evidence that vitamin A supplementation reduced infant mortality at two to 12 months (RR 1.08, 95% CI 0.77 to 1.52; 6090 participants; 5 RCTs; low-quality evidence). Effects on morbidity (gastroenteritis at three months) was uncertain (RR 6.03, 95% CI 0.30 to 121.82; 84 participants; 1 RCT; very low-quality evidence). There was low-quality evidence for the effect on infant adverse outcomes (bulging fontanelle at 24 to 48 hours) (RR 2.00, 95% CI 0.61 to 6.55; 444 participants; 1 RCT). Supplement (vitamin A as retinyl) 400,000 IU versus 200,000 IUThree studies (1312 participants) were included in this comparison. None of the studies assessed maternal mortality, maternal morbidity or infant mortality. Findings from one study showed that there may be little or no difference in infant morbidity between the doses (diarrhoea, respiratory illnesses, and febrile illnesses) (312 participants, data not pooled). No firm conclusion could be drawn on the impact on maternal and infant adverse outcomes (limited data available).The effect on breast milk retinol was also uncertain due to the small amount of information available.

AUTHORS' CONCLUSIONS

There was no evidence of benefit from different doses of vitamin A supplementation for postpartum women on maternal and infant mortality and morbidity, compared with other doses or placebo. Although maternal breast milk retinol concentrations improved with supplementation, this did not translate to health benefits for either women or infants. Few studies reported on maternal and infant mortality and morbidity. Future studies should include these important outcomes.

The effect of vitamin A supplementation with 400 000 IU vs 200 000 IU on retinol concentrations in the breast milk: A randomized clinical trial

BACKGROUND & AIMS

The vitamin A nutritional status is marginal for most of the newborns, and the prevention of that deficiency is promoted by breastfeeding. The Ministry of Health of Brazil established the National Vitamin A Supplementation Program, giving mega-doses of this nutrient to women right after delivery, in order to provide adequate vitamin A content in the breast milk and The International Vitamin A Consultative Group has supported the recommendation, to supplement with 400 000 IU of VA immediately after delivery. This study compares retinol concentrations in breast milk (colostrum, 2 and 4 months) from mothers supplemented during immediate postpartum with 400 000 IU versus 200 000 IU of vitamin A.

METHODS

A randomized, controlled, triple-blind trial, conducted in two public maternities in Recife, Northeast Brazil. Two hundred and ten mothers were recruited and allocated into two treatment groups: 400 000 IU or 200 000 IU of Vitamin A and monitored for 4 months.

RESULTS

There was no significant difference between retinol concentrations in breast milk between treatment groups (400 000 IU vs 200 000 IU) in the studied period: 2 months (p = 0.790) and 4 months (p = 0.279), although a progressive reduction of concentrations throughout the study was observed in both treatment groups, 400 000 IU (p < 0.0001) and 200 000 IU (p < 0.0001).

CONCLUSIONS

The absence of an additional effect of a higher dosage justifies the 200 000 IU supplementation, according to the World Health Organization. Registered under ClinicalTrials.gov Identifier No. NCT00742937.

Effect of maternal vitamin A supplementation on retinol concentration in colostrum

OBJECTIVE

To investigate the effect of vitamin A supplementation on the retinol concentration in colostrum under fasting and postprandial conditions.

METHODS

This was a quasi-experimental study, with before and after assessments, conducted with 33 patients treated at a public maternity hospital. Blood and colostrum samples were collected under fasting conditions in the immediate postpartum period. A second colostrum collection occurred two hours after the first meal of the day, at which time a mega dose of 200,000 IU of retinyl palmitate was administered. On the following day, the colostrum was collected again under fasting and postprandial conditions. Serum and colostrum retinol concentrations were determined by high performance liquid chromatography.

RESULTS

The serum retinol concentration was 37.3 (16.8-62.2) μg/dL, indicating adequate nutritional status. The colostrum retinol concentration before supplementation was 46.8 (29.7-158.9) μg/dL in fasting and 67.3 (31.1-148.7) μg/dL in postprandial condition (p < 0.05), showing an increase of 43.8%. After supplementation, the values were 89.5 (32.9-264.2) μg/dL and 102.7 (37.3-378.3) μg/dL in fasting and postprandial conditions, respectively (p < 0.05), representing an increase of 14.7%.

CONCLUSIONS

This study demonstrated that maternal supplementation with high doses of vitamin A in postpartum resulted in a significant increase of the retinol concentration in colostrum under fasting conditions, with an even greater increase after a meal.

Vitamin A supplementation for postpartum women

BACKGROUND

In vitamin A deficient populations, the amount of vitamin A may be insufficient for maintenance of maternal health and levels in breast milk may be insufficient for breastfeeding infants' needs.

OBJECTIVES

To assess the effects of postpartum maternal vitamin A supplementation on maternal and infant health.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 July 2010), LILACS (1982 to July 2010), Web of Science (1945 to July 2010) and Biological Abstracts (1998 to July 2010).

SELECTION CRITERIA

Randomised controlled trials evaluating the effects of postpartum maternal vitamin A supplementation.

DATA COLLECTION AND ANALYSIS

Two review authors assessed the studies independently.

MAIN RESULTS

We included 12 trials at moderate risk of bias, enrolling 25,465 mother-baby pairs and comparing several postpartum doses (200,000-400,000 IU) of vitamin A or 7.8 mg daily beta-carotene, with placebo, iron or no supplement; or higher (400,000 IU) versus lower dose (200,000 IU). The majority of infants in all studies were at least partially breastfed for six months.Maternal: we observed no impact of vitamin A on maternal mortality (two trials of 9,126 women), morbidity (one trial of 50 women) or adverse effects (subset of 786 women in one trial). Vitamin A enhanced serum and breast milk retinol at three months in five trials, but these improvements were generally not sustained.Infant: we observed no significant differences for infant mortality RR 1.14 95% CI 0.84 to 1.57 (five trials (6,170 infants) or morbidity (three trials) except for fewer episodes of fever with vitamin A in one small trial. No significant differences in infant vitamin A status were seen with maternal vitamin A supplementation (five trials).No beneficial effects for maternal or infant health were associated with higher compared to lower doses of vitamin A in two trials.

AUTHORS' CONCLUSIONS

The lack of effect on maternal and infant mortality and morbidity, with exception of some improved infant morbidity in one small study, and the improvement in maternal vitamin A status, suggest that maternal postpartum vitamin A supplementation offers limited benefits.