Selenium status and infant birth weight among HIV-positive and HIV-negative pregnant women in Lagos, Nigeria.

Background: During pregnancy, selenium deficiency and reduced antioxidant activities may result in adverse perinatal outcome such as low birthweight, which is associated with significant perinatal morbidity and mortality. Many studies have reported conflicting findings on the relationship between maternal selenium status and infant birth weight.

Objective: This study is to determine the relationship between maternal serum selenium concentration and infant birthweight in HIV-positive and HIV-negative pregnant women at term.

Methods: A cross-sectional study carried out among HIV-positive and HIV-negative pregnant women at term. Participants were recruited from the antenatal clinic at the Lagos University Teaching Hospital. After obtaining an informed consent, participants were interviewed using a structured questionnaire. Five milliliters of venous blood sample was collected from each participant for estimation of selenium levels using the Inductively Coupled Plasma Mass Spectrometry (ICP-MS) method. At delivery, the infant birth weights were measured using a standard infant weighing scale.

Results: Of the 240 participants, data were complete for analysis in 214 (89.2%) of the participants. HIV-positive women had significantly lower mean serum selenium concentration when compared with HIV-negative women (33.7 +/- 22.2 pg/L versus 83.6 +/- 18.7 pg/L; p<0.01). Compared with HIV-negative women, the mean birth weight of infants of HIV positive women was significantly lower (2952 +/- 572 g versus 3392 +/- 452 g; p<0.01). There was no significant association between maternal serum selenium levels at term and infant birth weight in both groups.

Conclusion: HIV-positive pregnant women had a lower mean serum selenium level and their infants had a lower mean birth weight, when compared to HIV-negative pregnant women. However, no significant association was found between maternal serum selenium concentration and birth weight in both groups.