Baseline Iron Status and Indices of Oxidative Stress in a Cohort of Pregnant Women in Kinshasa, DR Congo

Abstract

Objective: To determine baseline iron and oxidative status in a cohort of pregnant women before iron supplementation in our setting. Background: Screening of iron deficiency before supplementation during pregnancy has been scarce. Therefore, following routine iron supplementation confounding results might be found in outcomes of groups of patients considered. Taking in account that body/serum iron status is reportedly linked to maternal oxidative status, we aimed to associate assessment of baseline iron and oxidative status of women in need of oral supplementation during pregnancy. Methods: This is a cross-sectional study concerning 74 women attending antenatal care at the University Clinics of Kinshasa from September 2017 throughout June 2018, with a singleton pregnancy not exceeding 19 weeks, regardless of age and parity. Variables of the study included sociodemographic and anthropometric ones along with parameters of iron status (hemoglobin, hematocrit, ferritin, serum iron, transferrin and iron saturation capacity). Oxidative status was assessed using superoxide dismutase (SOD) and uric acid as antioxidants, while oxidant agents were oxidized LDL and blood glucose (beside serum iron and ferritin). According to local standards anemia was defined as hemoglobin < 10 g/L and pathologic serum ferritin as < 15 ng/ml. For statistical calculations we used t-test, chi-square test and Pearson's correlation test, the significance being stated at p ≤ 0.05. Results: At recruitment (15.9 ± 1.7 9 week gestational age) mean hemoglobin value of the overall study group was 10.3 ± 1.5 g/dl. Anemia was diagnosed to 39 women that represented 52.2% of the study group, most of anemic women belonging to low socioeconomic sub-group (69.2% vs 29%; P < 0.001). The majority was para 2, with average weight of 70.2 ± 14.5 Kg (P not significant between sub-groups) and BMI of 26 ± 5.2 Kg/m 2 (P < 0.01).higher among anemic women (61.5% vs 34.3%; P < 0.02) that had lower alimentary iron intake (22.8 ± 4.9 gr/day vs 31.4 ± 9.5 gr; P < 0.001). Of markers of iron status serum ferritin and iron were lower in anemic women (7.5 ± 3.9 ng/ml vs 35.7 ± 17.1 ng/ml; P < 0.001 and 52.7 ± 38.9 μg/dl vs 96.2 ± 41.8 μg/dl, respectively. Both sub-groups were similar in serum transferrin. As of markers of oxidative stress anemic women had significantly higher superoxide dismutases (SOD) (1056.4 ± 762.1 UI/L vs 682.6 ± 543.9 UI/L (P < 0.02) and oxidizedd anti LDL Ac (439.6 ± 209.5 UI/L vs 192.8 ± 136.3 UI/L (P < 0.001). Serum iron, ferritin, SOD and oxidized LDL were more likely to assess iron and oxidative status in our setting. Conclusion: The rate of anemic mothers found in our study (52.2%) has been quite constant in our setting for years, meaning endemicity. Serum iron and ferritin were significantly lower in anemic women, which is supportive of routine iron supplementation during pregnancy. Significantly higher level of SOD and oxidized LDL in anemic women suggests that maternal anemia may count into oxidative stress likely to be found in these women.

Routine Iron Supplementation during Pregnancy: Its Reflection on Iron and Oxidative Status in a Cohort of Pregnant Women in Kinshasa, DR Congo

“…Markers n 14 -19 GA (1) 28 -32 SA (2) At term (3) p (1)(2) p (1-3) p 2-3) p (1-2-3) Hemoglobin (mg/dl) It can be seen that significant associations with oxidative stress appeared only for oxidized LDL after ≥ 20 weeks of supplementation (OR = 7.04; CI95%: 2.5 -19.7; p < 0.001). This concerns mostly anemic women for which iron was provided earlier than non anemic.…”

“…The proportion of obeses was 18.9%. Of their general characteristics already presented in a previous paper [2], Table 1 includes those for which significant differences were observed at recruitment between anemic and non anemic women, namely socioeconomic status (lower in anemic group), BMI (higher in anemic group), nutritional iron intake (lower in anemic group) and intestinal parasitosis (more frequent in anemic group). The duration of supplementation and eating habits likely to impede iron absorption (Geophagia, fibers and tannins consumption) were also included.…”

“…The sampling was carried out consecutively for all pregnant women presenting themselves at prenatal care until completion of 74 women (the minimum size of 54 as calculated according to appropriate formulas + 20 women for potential drop out). It is a prospective observational one concerning a cohort of 74 healthy pregnant women with singleton pregnancy of < 19 weeks of gestation whose baseline iron and oxidative status have been recently assessed at university clinics of Kinshasa, DR Congo [2]. Only women reaching fetal viability (28 weeks of gestation) were selected.…”

“…Additionally to baseline measurements at recruitment (±15 weeks of gestation) blood sampling and analysis were carried out at 28 -32 weeks and at term in conditions previously described [2]. Biological parameters were: hemoglobin, hematocrit, ferritin, serum iron, transferrin and iron saturation capacity for iron status and SOD, uric acid, oxidized LDL and fasting blood glucose for oxidative status.…”

“…In a previous study [2] we assessed baseline iron and oxidative status of pregnant women just before the period scheduled to start routine iron supplementation in our setting. We found that the majority of pregnant women were anemic.…”