Impact of vitamin A supplementation on anaemia and plasma erythropoietin concentrations in pregnant women: a controlled clinical trial.

INTRODUCTION: Although studies suggest that vitamin A or its metabolites influence the synthesis of erythropoietin in vitro and in animal models, it is unclear whether vitamin A supplementation increases plasma erythropoietin concentrations in humans. OBJECTIVE: To determine whether daily vitamin A supplementation increases plasma erythropoietin concentrations in pregnant women with a high prevalence of anaemia. METHODS: A randomized, double-blind, controlled clinical trial was conducted to examine the effect of daily vitamin A (3000 microg retinol equivalent), iron (30 mg), and folate (400 microg) versus iron (30 mg) and folate (400 microg) (control) on haemoglobin and plasma erythropoietin concentrations in 203 pregnant women in Malawi, Africa. RESULTS: Mean gestational age at enrollment was 23 wk, at which time 50% of the women were anaemic (haemoglobin <110 g/L). Mean (+/-SEM) change in haemoglobin from enrollment to 38 wk was 4.7+/-1.6 g/L (p=0.003) and 7.3+/-2.3 g/L (p=0.003) in the vitamin A and control groups, respectively. Mean change in plasma erythropoietin concentrations from enrollment to 38 wk was 2.39+/-5.00 (p=0.63) and -2.87+/-3.92 IU/L (p=0.46) in the vitamin A and controls groups, respectively. There were no significant differences between vitamin A and control groups in the slope of the regression line between log10 erythropoietin and haemoglobin at enrollment or 38 wk, and between enrollment and follow-up within either group. CONCLUSIONS: Vitamin A supplementation does not appear to increase haemoglobin and plasma erythropoietin concentrations among pregnant women with a high prevalence of anaemia in Malawi.

The situation in Africa.

More than three million women world-wide are infected with HIV, and women will constitute 40% of the new AIDS cases in 1990-1991. Unlike in the industrialized world, HIV in Africa is heterosexually transmitted and thus affects at least as many women as men. Already the leading cause of death in a major African city, HIV may be spreading to rural areas. In spite of improvement in surveillance, under-reporting makes it difficult to project trends, document differences within and between urban and rural areas, and identify at-risk groups. Increasing evidence shows that STDs play a major role in spreading the HIV epidemic. Male-to-female transmission is more efficient owing to factors related to the pathogen and the host. Ulcerative STDs such as chancroid, syphilis and herpes facilitate HIV entry through mucosal discontinuation and recruitment of HIV target cells. The role of non-ulcerative STDs such as gonorrhoeal, chlamydial and trichomonal infections needs further elucidation. Lack of circumcision, traditional healing practices and oral contraceptives may affect the risk of viral transmission, but may not be major or modifiable risk factors. Pregnancy and pregnancy-associated immune alterations do not seem to affect the clinical course of HIV/AIDS in African women or impair immunocompetence. Maternal HIV can adversely affect pregnancy outcome in Africa, causing low birth-weight, prematurity, intrauterine and intrapartum fetal death. The risk for these outcomes is likely to depend on the degree of immunological and clinical deterioration. Breast-feeding does not appreciably increase the risk of HIV transmission to the infant and should be actively promoted in Africa. Control of HIV/AIDS in Africa, in the absence of an effective vaccine, will focus on behavioural changes through health education and condom use. High frequency STD transmitter core groups, mainly prostitutes and their clients, are currently the target of prevention campaigns which are proving to be successful and affordable.

PIP: More than 3 million women are infected with HIV worldwide. Further, 40% of new cases in 1990-91, will be among women. HIV and AIDS are overwhelmingly heterosexually related in Africa and affect similar proportions of both sexes. AIDS may, in fact, be the leading cause of death in some cities, and is thought to be spreading to rural areas through a highly mobile work force, multiple partners, and high rates of sexually transmitted disease (STD). Other biological and behavioral factors also contribute to the existence of the pattern of HIV transmission predominantly seen in Africa. Women and children are at particular risk of infection in African countries. STDs such as chancroid, syphilis, herpes, and gonorrhea; traditional healing practices and sexual behavior; lack of circumcision; and the use of oral contraceptives may all support HIV infection to varying degrees. Of STDs, chancroid, syphilis, and herpes are known to facilitate HIV entry by effecting mucosal discontinuation and recruiting HIV target cells. Pregnancy and pregnancy-associated immunal changes most likely do not affect the clinical course of HIV/AIDS in African women or harm their immune status. Maternal HIV may, however, cause newborns to be of low birth weight or premature, or increase the probability of intrauterine or intrapartum fetal death. Breast feeding does not significantly increase the risk of vertical HIV transmission and should continue to be promoted.