Prenatal Hemoglobin Levels and Early Cognitive and Motor Functions of One-Year-Old Children.

OBJECTIVE: To explore the relationship between prenatal hemoglobin (Hb) concentration and infant cognitive and motor functions. METHODS: Our prospective cohort study included 1-year-old children born to women enrolled at their first antenatal care (ANC) visit in Allada, Benin, before 29 weeks of pregnancy, within a trial comparing the efficacy of sulfadoxine-pyrimethamine and mefloquine. Hb concentrations of pregnant women were determined from venous blood samples collected at first and second ANC visits of at least 1-month interval and at delivery. Women were prescribed oral iron, folic acid, and anthelminthics after the first ANC visit. A total of 636 children (76.8% of eligible children) were assessed by trained research nurses for cognitive and motor functions by using the Mullen Scales of Early Learning. RESULTS: Prevalence of anemia (Hb < 110 g/L) decreased from 67.0% at first ANC visit (mean gestational age [SD], 22.1 [4.0] weeks) to 38.4% at delivery. Mean (SD) Hb concentrations increased from 103.7 (12.3) at first ANC visit to 112.4 (14.1) at delivery. We observed a significant negative quadratic relationship between infant gross motor (GM) function and Hb concentration at first and second ANC visits. Thus, infant GM scores increased sharply with increasing maternal Hb concentration until 90 g/L where increasing GM was mild, and began to decline after 110 g/L. CONCLUSIONS: There appears to be an Hb concentration range that may be optimal for GM function of 1-year-old children. This may reflect the importance of physiologic hemodilution, which occurs after the second trimester until 34 weeks of gestation.

Maternal anemia in pregnancy: assessing the effect of routine preventive measures in a malaria-endemic area.

We investigated the effectiveness of routine preventive measures for anemia in Beninese pregnant women during pregnancy. Anemia (hemoglobin < 110 g/L) was common: 68.3% at first antenatal visit (ANV1), 64.7% at second antenatal visit (ANV2), and 40.6% at delivery. Parasitic infections and nutritional deficiencies were the most preventable causes. After intermittent preventive treatment (IPTp) and antihelminthic treatments, malaria prevalence decreased from 15.1% (ANV1) to 4.0% (ANV2) and increased again to 9.6% at delivery. Helminth infections dropped from 11.1% (ANV1) to 7.2% (ANV2) and 2.4% at delivery. Malaria was associated with lower mean hemoglobin on ANV1 and delivery, and iron deficiency was associated with lower mean hemoglobin on ANV1 and ANV2. IPTp and antihelminthic treatments were efficacious to clear parasitic infections and improve hematologic status, whereas the effectiveness of daily iron and folic acid supplements to correct iron and folate deficiencies and decrease anemia was less marked, possibly because of lack of compliance.

Malaria and gravidity interact to modify maternal haemoglobin concentrations during pregnancy.

BACKGROUND: Primigravidity is one of the main risk factors for both malaria and anaemia. Since the implementation of intermittent preventive treatment (IPTp) in sub-Saharan Africa, the relationship between anaemia and gravidity and its evolution during pregnancy has been little explored. This study aimed to evaluate the impact of gravidity on the variation of haemoglobin during pregnancy according to the timing of gestation. METHODS: Data from three studies carried out in nearby areas in south Benin (Ouidah, Comé, Allada) between 2005 and 2012 were analysed. At inclusion (first antenatal visit, ANV1) women's age, area of residence, schooling, gravidity, gestational age, weight and height were recorded. Thick blood smears were performed on ANV1, second visit (ANV2) and at delivery. In Allada, women's serum ferritin and CRP concentrations were also assessed. The impact of gravidity on maternal haemoglobin (Hb) was analysed using a logistic or linear regression depending on the outcome. The statistical significance was set to P < 0.05. RESULTS: In total, data from 3,591 pregnant women were analysed. Both univariate and multivariate analyses showed a constant association between Hb concentrations and gravidity in the three periods of Hb assessment (ANV1, ANV2 and delivery). Mean Hb concentration was significantly lower in primigravidae than in multigravidae at ANV1 (mean difference = -2.4 g/L, CI 95%: [-3.4, -1.4], P < 0.001). Afterwards, there was a significant increase in primigravidae only, with a tendency to reversal between primigravidae and multigravidae, which was confirmed at delivery (mean difference = 2.8 g/L, CI 95%: [1.3, 4.2], P < 0.001). The prevalence of malaria infection was halved between ANV1 and delivery in primigravidae while it decreased by only 38% among multigravidae, who were less prone to malaria infection (prevalence at ANV1, 20% and 10% respectively). Iron deficiency was more common in multigravidae, and it decreased slightly in this group between ANV1 and delivery. CONCLUSION: In a context of IPTp, Hb levels improved progressively throughout pregnancy in primigravidae, likely as a result of reduction in malaria infection. In multigravidae, the improvement was less perceptible and anaemia was mainly due to iron deficiency.

Maternal anemia at first antenatal visit: prevalence and risk factors in a malaria-endemic area in Benin.

The risk factors for maternal anemia (hemoglobin level less than 110 g/L) were studied in human immunodeficiency virus-negative pregnant women in Benin at the time of first antenatal visit and prior to any prevention. Data for the first 1,005 pregnant women included in a multicentre randomized controlled trial were analyzed. Anemia was common (68.3%), and malaria and helminth infestations were prevalent in 15.2% and 11.1% of the women. A total of 33.3%, 31.3% and 3.6% of the women were iron, folic acid and vitamin B12 deficient, respectively. These parasitic infections and nutrient deficiencies were associated with a high risk of anemia. Twenty-one percent, 15%, 12%, 11% and 7% of anemia were attributable to malnutrition, malaria, iron, folic acid deficiencies, and helminth infestations, respectively. Most anemia was caused by factors that could be prevented by available tools, stressing the need to reinforce their implementation and to evaluate their effectiveness throughout the course of the pregnancy.