Effect of vitamin A on maternal, fetal, and neonatal outcomes: An overview of deficiency, excessive intake, and intake recommendations

Vitamin A imbalance during pregnancy and lactation is a global public health concern with potentially negative consequences for fetuses and neonates. Inadequate vitamin A intake during this critical period can lead to anemia, weakened immune function, night blindness, and increased susceptibility to infections. Conversely, excessive intake of vitamin A can result in birth defects, hypercalcemia, and psychiatric symptoms. This review aims to identify risk factors contributing to vitamin A deficiency in pregnant women and its impact on maternal, fetal, and neonatal outcomes. It also examines the effects of high-dose vitamin A supplementation during pregnancy on offspring health. By analyzing existing literature and recommendations, the review emphasizes the significance of vitamin A in the development of various body systems and organs. It provides a comprehensive overview of the effects of vitamin A during pregnancy and lactation, encompassing deficiencies, excessive intake, and supplementation guidelines. The need for further research in this field is highlighted. In conclusion, maintaining a balanced vitamin A status is crucial during pregnancy to promote better outcomes for fetuses and newborns. Effective monitoring and intervention strategies are essential to address vitamin A deficiency and excess in pregnant women, thereby improving fetal and neonatal health.

Patisiran exposure in early pregnancy: a case report

We describe here the first case of exposure to patisiran treatment, a small interfering RNA molecule, during early pregnancy of a 36-year-old woman with symptomatic hereditary transthyretin-related amyloidosis. There were no major complications during pregnancy and delivery, except for a postpartum hemorrhage due to uterine atony. Vitamin A levels had to be closely monitored during pregnancy, and vitamin A substitution adapted accordingly. There was no sign of minor or major congenital abnormalities of the baby. One month after delivery, the patient showed slight clinical and electrophysiological signs of neuropathy progression due to patisiran treatment withdrawal. Patisiran infusions were resumed 3 months after delivery. Due to the unknown teratogenic potential of patisiran, the risk of neuropathy worsening associated with withholding treatment must of course be weighed against a potential teratogenic risk of treatment during pregnancy. Vitamin A levels need to be closely assessed, and substitution must be adapted accordingly, to avoid embryofetal adverse outcome due to vitamin A deficiency or toxicity.

Vitamin A deficiency among pregnant women in Ethiopia: a systematic review and meta-analysis

BACKGROUND

Vitamin A deficiency (VAD) during pregnancy is a public health challenge in low-income countries. There are inconsistent findings that can affect policy in planning appropriate intervention. This systematic review and meta-analysis were conducted to summarize the evidence in order to identify existing gaps and propose strategies to reduce VAD during pregnancy in Ethiopia.

METHODS

This study included published and unpublished observational studies searched from different databases (PubMed, CINHAL [EBSCO], Embase, Google Scholar, Directory of Open Access Journals, Web of Sciences, MEDLINE, Cochrane Library, Scopus, Google Search and MedNar). Statistical analysis was conducted using Stata version 14 software. Heterogeneity and publication bias were assessed. Forest plots were used to present the pooled prevalence using the random effects model.

RESULTS

A total of 37 618 pregnant women from 15 studies were included. The overall pooled prevalence of VAD was 29% (95% confidence interval 21 to 36) with I2=99.67% and p<0.001. Socio-economic and sociodemographic factors were identified as affecting vitamin A deficiencies among pregnant women.

CONCLUSIONS

Nearly one-third of pregnant women in Ethiopia had VAD. Strengthening intervention modalities that aimed to increase the uptake of vitamin A-rich foods can avert VAD among pregnant women in Ethiopia.

Plasma Retinol Concentrations and Dietary Intakes of Mother-Infant Sets in Singleton versus Twin Pregnancy

Vitamin A (retinol) is essential for normal fetal development, but the recommendation for maternal dietary intake (Retinol Activity Equivalent, RAE) does not differ for singleton vs. twin pregnancy, despite the limited evaluation of retinol status. Therefore, this study aimed to evaluate plasma retinol concentrations and deficiency status in mother-infant sets from singleton vs. twin pregnancies as well as maternal RAE intake. A total of 21 mother-infant sets were included (14 singleton, 7 twin). The HPLC and LC-MS/HS evaluated the plasma retinol concentration, and data were analyzed using the Mann-Whitney U test. Plasma retinol was significantly lower in twin vs. singleton pregnancies in both maternal (192.2 vs. 312.1 vs. mcg/L, p = 0.002) and umbilical cord (UC) samples (102.5 vs. 154.4 vs. mcg/L, p = 0.002). The prevalence of serum-defined vitamin A deficiency (VAD) <200.6 mcg/L was higher in twins vs. singletons for both maternal (57% vs. 7%, p = 0.031) and UC samples (100% vs. 0%, p < 0.001), despite a similar RAE intake (2178 vs. 1862 mcg/day, p = 0.603). Twin pregnancies demonstrated a higher likelihood of vitamin A deficiency in mothers, with an odds ratio of 17.3 (95% CI: 1.4 to 216.6). This study suggests twin pregnancy may be associated with VAD deficiency. Further research is needed to determine optimal maternal dietary recommendations during twin gestation.

A Study to Improve the Vitamin A and Iodine Status of Pregnant Women through a Multiple Micronutrient Fortified Salt

Background. To study the efficacy of a multiple micronutrient fortified salt enriched with iron, iodine, vitamin A, vitamin B1, vitamin B2, vitamin B6, vitamin B12, niacin, and folic acid in improving serum retinol and iodine status of pregnant women. Methods. It was a randomized control trial in the antenatal clinic of a hospital. 151 women in the experimental group received a multiple micronutrient fortified salt to cook all their meals, and 150 women in the control group did not receive the fortified salt. Blood was collected in the three trimesters. Urine was collected in their first and third trimesters. Serum retinol, CRP (C-reactive protein), and AGP (Alpha glycoprotein) in blood were assessed, and iodine was assessed in urine. All the women were dewormed once. Results. The inflammation adjusted mean serum retinol in three trimesters in the experimental group was 24.51, 27.29, and 25.68 µg/dL, and it was 28.97, 27.63, and 22.72 µg/dL in the control group. Over the study period of 6 months, the increase in serum retinol in the experimental group was 1.17 µg/dL whereas in the control group serum retinol decreased by 6.25 µg/dL. The experimental group increase in serum retinol is significantly more ( $p=0.0001$ ) than the changes in retinol in the control group. The prevalence of serum retinol deficiency in the three trimesters was 39.1%,25.8%, and 37.7% in the experimental group and 14%, 22.7%, and 39.3% in the control group, and the change in the experimental group was significant ( $p=0.001$ ) compared to the control group by binary logistic regression. Over the study period of 6 months there is a significant increase in urinary iodine concentration in the experimental group ( $p=0.030$ ), showing absorption of iodine from the fortified salt whereas there is a significant decline in the iodine values in the control group ( $p=0.008$ ). At the end of the study, the urinary iodine concentration of the experimental group was significantly more ( $p=0.0001$ ) than that of the control group. Conclusion. The fortified salt was able to improve serum retinol levels and urinary iodine levels in pregnant women. Trial Registration. This trial was registered retrospectively on 19/02/2022 in the ISRCTN registry with trial ID ISRCTN17782574.

Effect of vitamin A, calcium and vitamin D fortification and supplementation on nutritional status of women: an overview of systematic reviews

BACKGROUND

Micronutrient deficiency affects the health and development of vulnerable population such as children and pregnant women. Measures such as fortification of food and supplementation have been implemented to prevent or control deficiencies related to micronutrients.

OBJECTIVE

To assess the effect of vitamin A, vitamin D, and calcium fortification and supplementation on nutritional status of women in reproductive age group. To assess the toxicities and adverse events related to intervention.

METHODOLOGY

Systematic reviews including RCTs on women of reproductive age group provided with vitamin A, vitamin D, and calcium supplementation or fortified food were included, to report all malnutrition-related outcomes due to deficiency of the abovementioned micronutrients. The Cochrane Database of Systematic Reviews, EPPI Centre, Campbell Collaboration, PubMed, Web of Science, and Scopus were searched electronically for English language publications, until 31 March 2018. Hand searching of the articles was done from the Journal of Food Science and Technology. Two independent reviewers selected the systematic reviews, extracted data, and assessed for the quality.

RESULTS

A total of 16 systematic reviews were included in narrative synthesis. Supplementation of vitamin A was reported to result in increased maternal serum retinol concentrations and increased breast milk retinol concentration. It reduced the risk of anemia (Hb < 11 g/dL) and reduced maternal clinical infection. Vitamin D supplementation increased 25-hydroxy vitamin D levels. There was insufficient evidence for the effect on bone mineral density and serum calcium levels. Calcium supplementation did not have any significant effect on body weight, weight gain, and body mass index of the participants.

CONCLUSION

This overview of systematic reviews reiterates the nutritional importance of vitamin A, vitamin D, and calcium supplementation for the reproductive age women. However, there was no empirical evidence available for fortification of food with vitamin A, vitamin D, and calcium and nutritional benefits of the same for reproductive age women, therefore thrusting upon the need of conducting future quality research, i.e., clinical trials and systematic reviews for food fortification.

SYSTEMATIC REVIEW REGISTRATION

A priori protocol for this overview of systematic reviews was registered in PROSPERO with registration number CRD42018089403 .

Fortification of staple foods with vitamin A for vitamin A deficiency

BACKGROUND

Vitamin A deficiency is a significant public health problem in many low- and middle-income countries, especially affecting young children, women of reproductive age, and pregnant women. Fortification of staple foods with vitamin A has been used to increase vitamin A consumption among these groups.

OBJECTIVES

To assess the effects of fortifying staple foods with vitamin A for reducing vitamin A deficiency and improving health-related outcomes in the general population older than two years of age.

SEARCH METHODS

We searched the following international databases with no language or date restrictions: Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 6) in the Cochrane Library; MEDLINE and MEDLINE In Process OVID; Embase OVID; CINAHL Ebsco; Web of Science (ISI) SCI, SSCI, CPCI-exp and CPCI-SSH; BIOSIS (ISI); POPLINE; Bibliomap; TRoPHI; ASSIA (Proquest); IBECS; SCIELO; Global Index Medicus - AFRO and EMRO; LILACS; PAHO; WHOLIS; WPRO; IMSEAR; IndMED; and Native Health Research Database. We also searched clinicaltrials.gov and the International Clinical Trials Registry Platform to identify ongoing and unpublished studies. The date of the last search was 19 July 2018.

SELECTION CRITERIA

We included individually or cluster-randomised controlled trials (RCTs) in this review. The intervention included fortification of staple foods (sugar, edible oils, edible fats, maize flour or corn meal, wheat flour, milk and dairy products, and condiments and seasonings) with vitamin A alone or in combination with other vitamins and minerals. We included the general population older than two years of age (including pregnant and lactating women) from any country.

DATA COLLECTION AND ANALYSIS

Two authors independently screened and assessed eligibility of studies for inclusion, extracted data from included studies and assessed their risk of bias. We used standard Cochrane methodology to carry out the review.

MAIN RESULTS

We included 10 randomised controlled trials involving 4455 participants. All the studies were conducted in low- and upper-middle income countries where vitamin A deficiency was a public health issue. One of the included trials did not contribute data to the outcomes of interest.Three trials compared provision of staple foods fortified with vitamin A versus unfortified staple food, five trials compared provision of staple foods fortified with vitamin A plus other micronutrients versus unfortified staple foods, and two trials compared provision of staple foods fortified with vitamin A plus other micronutrients versus no intervention. No studies compared staple foods fortified with vitamin A alone versus no intervention.The duration of interventions ranged from three to nine months. We assessed six studies at high risk of bias overall. Government organisations, non-governmental organisations, the private sector, and academic institutions funded the included studies; funding source does not appear to have distorted the results.Staple food fortified with vitamin A versus unfortified staple food We are uncertain whether fortifying staple foods with vitamin A alone makes little or no difference for serum retinol concentration (mean difference (MD) 0.03 μmol/L, 95% CI -0.06 to 0.12; 3 studies, 1829 participants; I² = 90%, very low-certainty evidence). It is uncertain whether vitamin A alone reduces the risk of subclinical vitamin A deficiency (risk ratio (RR) 0.45, 95% CI 0.19 to 1.05; 2 studies; 993 participants; I² = 33%, very low-certainty evidence). The certainty of the evidence was mainly affected by risk of bias, imprecision and inconsistency.It is uncertain whether vitamin A fortification reduces clinical vitamin A deficiency, defined as night blindness (RR 0.11, 95% CI 0.01 to 1.98; 1 study, 581 participants, very low-certainty evidence). The certainty of the evidence was mainly affected by imprecision, inconsistency, and risk of bias.Staple foods fortified with vitamin A versus no intervention No studies provided data for this comparison.Staple foods fortified with vitamin A plus other micronutrients versus same unfortified staple foods Fortifying staple foods with vitamin A plus other micronutrients may not increase the serum retinol concentration (MD 0.08 μmol/L, 95% CI -0.06 to 0.22; 4 studies; 1009 participants; I² = 95%, low-certainty evidence). The certainty of the evidence was mainly affected by serious inconsistency and risk of bias.In comparison to unfortified staple foods, fortification with vitamin A plus other micronutrients probably reduces the risk of subclinical vitamin A deficiency (RR 0.27, 95% CI 0.16 to 0.49; 3 studies; 923 participants; I² = 0%; moderate-certainty evidence). The certainty of the evidence was mainly affected by serious risk of bias.Staple foods fortified with vitamin A plus other micronutrients versus no interventionFortification of staple foods with vitamin A plus other micronutrients may increase serum retinol concentration (MD 0.22 μmol/L, 95% CI 0.15 to 0.30; 2 studies; 318 participants; I² = 0%; low-certainty evidence). When compared to no intervention, it is uncertain whether the intervention reduces the risk of subclinical vitamin A deficiency (RR 0.71, 95% CI 0.52 to 0.98; 2 studies; 318 participants; I² = 0%; very low-certainty evidence) . The certainty of the evidence was affected mainly by serious imprecision and risk of bias.No trials reported on the outcomes of all-cause morbidity, all-cause mortality, adverse effects, food intake, congenital anomalies (for pregnant women), or breast milk concentration (for lactating women).

AUTHORS' CONCLUSIONS

Fortifying staple foods with vitamin A alone may make little or no difference to serum retinol concentrations or the risk of subclinical vitamin A deficiency. In comparison with provision of unfortified foods, provision of staple foods fortified with vitamin A plus other micronutrients may not increase serum retinol concentration but probably reduces the risk of subclinical vitamin A deficiency.Compared to no intervention, staple foods fortified with vitamin A plus other micronutrients may increase serum retinol concentration, although it is uncertain whether the intervention reduces the risk of subclinical vitamin A deficiency as the certainty of the evidence has been assessed as very low.It was not possible to estimate the effect of staple food fortification on outcomes such as mortality, morbidity, adverse effects, congenital anomalies, or breast milk vitamin A, as no trials included these outcomes.The type of funding source for the studies did not appear to distort the results from the analysis.

Extraction of oil from high-moisture tuna liver by subcritical dimethyl ether: feasibility and optimization by the response surface method

The purpose of this paper is to explore the possibilities of subcritical dimethyl ether extraction (SDME) of oil from tuna liver with high-moisture content.

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.

Changes in the concentrations of biochemical indicators of diet and nutritional status of pregnant women across pregnancy trimesters in Trujillo, Peru, 2004-2005

BACKGROUND

In developing countries, deficiencies in essential micronutrients are common, particularly in pregnant women. Although, biochemical indicators of diet and nutrition are useful to assess nutritional status, few studies have examined such indicators throughout pregnancy in women in developing countries.

METHODS

The primary objective of this study was to assess the nutritional status of 78 Peruvian women throughout pregnancy for 16 different nutritional indicators including fat-soluble vitamins and carotenoids, iron-status indicators, and selenium. Venous blood samples from which serum was prepared were collected during trimesters one (n = 78), two (n = 65), three (n = 62), and at term via the umbilical cord (n = 52). Questionnaires were completed to determine the demographic characteristics of subjects. Linear mixed effects models were used to study the associations between each maternal indicator and the demographic characteristics.

RESULTS

None of the women were vitamin A and E deficient at any stage of pregnancy and only 1/62 women (1.6%) was selenium deficient during the third trimester. However, 6.4%, 44% and 64% of women had ferritin levels indicative of iron deficiency during the first, second and third trimester, respectively. Statistically significant changes (p ≤ 0.05) throughout pregnancy were noted for 15/16 nutritional indicators for this Peruvian cohort, with little-to-no association with demographic characteristics. Three carotenoids (beta-carotene, beta-cryptoxanthin and trans-lycopene) were significantly associated with education status, while trans-lycopene was associated with age and beta-cryptoxanthin with SES (p < 0.05). Concentrations of retinol, tocopherol, beta-cryptoxanthin, lutein + zeaxanthin and selenium were lower in cord serum compared with maternal serum (p < 0.05). Conversely, levels of iron status indicators (ferritin, transferrin saturation and iron) were higher in cord serum (p < 0.05).

CONCLUSION

The increasing prevalence of iron deficiency throughout pregnancy in these Peruvian women was expected. It was surprising though not to find deficiencies in other nutrients. The results highlight the importance of continual monitoring of women throughout pregnancy for iron deficiency which could be caused by increasing fetal needs and/or inadequate iron intake as pregnancy progresses.

Recovery from impaired dark adaptation in nightblind pregnant Nepali women who receive small daily doses of vitamin A as amaranth leaves, carrots, goat liver, vitamin A-fortified rice, or retinyl palmitate

BACKGROUND

It is not known whether daily consumption of vitamin A-containing foods is efficacious for treating nightblindness.

OBJECTIVE

We assessed the effect of supplementation with vitamin A from food or synthetic sources on dark adaptation and plasma retinol concentrations in nightblind pregnant Nepali women.

DESIGN

Nightblind pregnant women were randomly assigned to 1 of 6 treatment groups to receive 6 d/wk for 6 wk either 850 microg retinol equivalents/d as retinyl palmitate, vitamin A-fortified rice, goat liver, amaranth leaves, or carrots or 2000 microg retinol equivalents/d as retinyl palmitate. Dark adaptation was assessed weekly by using the pupillary threshold (PT) test; plasma retinol concentrations were measured before and after the intervention. These outcomes were also assessed in a comparison group of nonnightblind pregnant women.

RESULTS

In the nightblind women, the mean PT improved significantly (P<0.0001) from -0.71+/-0.04 to -1.42+/-0.02 log cd/m2, and the final mean PT did not differ significantly from that in the nonnightblind women (-1.43+/-0.04; P=0.55). Improvement in dark adaptation was greater in the liver group than in the vitamin A-fortified rice group (P<0.02). Plasma retinol concentrations increased significantly (P<0.0001) from 0.95+/-0.05 to 1.07+/-0.05 micromol/L. The plasma retinol response was greater in the higher-dose capsule and liver groups than in the vegetable groups and significantly greater in the liver group than in the vitamin A-fortified rice group (both: P<0.05).

CONCLUSION

Improvement in dark adaptation did not differ significantly between women who received vitamin A as liver, amaranth leaves, carrots, or retinyl palmitate.