Toxic metals levels in cord and maternal blood and possible association with low birth weight of babies

Abstract

Background: The birth weight of neonates is a reflection of the maternal health, nutritional status, and environmental exposure to toxic metals. Very few studies have evaluated prenatal exposure to toxic metals and its possible association with small for date’s babies in Nigeria. Objective: The objective of this study was to evaluate the levels of lead, cadmium, and mercury in maternal and cord blood among pregnant women at delivery and to ascertain whether there is any relationship between toxic metals levels and neonatal birth weight. Materials and Methods: A total of 300 subjects were recruited, which included 200 healthy pregnant women who were attending antenatal clinic and 100 age-matched non-pregnant women (controls). The concentrations of toxic metals in the cord and maternal blood were measured using atomic absorption spectrophotometer. Results: The maternal and cord blood levels of lead, cadmium, and mercury were significantly higher (P < 0.001) in small for date’s babies than in babies with normal birth weight. There was a significant positive correlation between cord blood lead (r = 0.088, P = 0.02) and cadmium (r = 0.119, P = 0.03) with neonatal birth weight. There was, however, no significant association (r = 0.009; P = 0.89) between mercury and neonatal birth weight. Conclusion: The levels of the measured toxic metals were significantly higher in maternal and cord blood of those who had small for date babies than those who had babies with normal birth weight. This study indicated that increased levels of toxic metals may be associated with small for date’s babies.