Maternal Serum Concentrations of Selenium, Copper and Zinc during Pregnancy are associated with Risk of Spontaneous Preterm Birth: A case-control study from Malawi

Abstract

Preterm birth is delivery before 37 completed weeks. A study was conducted to evaluate the association of maternal serum concentrations of selenium, copper, and zinc, and preterm birth. There were 181 women in this nested case- control study, 90/181 (49.7%) term and 91/181 (50.3%) preterm pregnant women. The overall mean serum concentration of selenium was 77.0; SD 19.4microg/L, copper was 2.50; SD 0.52 mg/L and zinc was 0.77; SD 0.20 mg/L with reference values of 47-142microg/L, 0.76-1.59mg/L and 0.59-1.11 mg/L, respectively. For preterm birth, mean serum concentrations for selenium was 79.7; SD 21.6microg/L, copper was 2.61; SD 0.57 mg/L, and zinc was 0.81; SD 0.20 mg/L compared to that of term births: selenium (74.2; SD 16.5microg/L; p=0.058), copper (2.39; SD 0.43 mg/L; p = 0.004), and zinc (0.73; SD 0.19 mg/L; p = 0.006) respectively. In adjusted analysis, every unit increase in maternal selenium concentrations gave increased odds of being a case OR 1.01 (95% CI: 0.99; 1.03), p=0.234, copper OR 1.62 (95% CI: 0.80; 3.32); p = 0.184, zinc OR 6.88 (95% CI: 1.25; 43.67); p=0.032. Results show that there was no deficiency of selenium, and zinc; and high serum concentrations of copper in pregnancy. Preterm birth was associated with higher maternal serum concentrations of copper and zinc.

Inverse association between maternal serum concentrations of trace elements and risk of spontaneous preterm birth: a nested case–control study in China

“…In the present study, no statistically significant association was found between maternal concentrations of Fe and the risk of SPTB, which was similar to an earlier report from a small birth cohort study in Australian women (33) and two studies from a prospective birth cohort in rural Bangladesh (24,38) . Besides, we did not observed a statistically significant association between the maternal concentrations of Cu and the risk of SPTB, which was consistent with four previous studies, a case-control study from Malawi about association analysis between maternal serum Cu and SPTB (37) , a prospective birth cohort in rural Bangladesh about the relationship between cord serum or maternal serum Cu and PTB (24,38) , and a nested case-control study in Beijing Birth Cohort (BBC), China, about association analysis between Cu concentrations in maternal hair and overall PTB as well as SPTB (21) . In addition, no statistically significant association was found between maternal concentrations of Zn and risk of SPTB, and this was similar to four previous study, including one analysis of maternal urine Zn concentrations and SPTB (32) , one study on maternal plasma Zn concentrations and SPTB (33) , one meta-analysis (39) , and another study on maternal serum Zn concentrations and SPTB (31) .…”

“…Some studies have reported significant associations between the deficiency of trace elements and increased risk of PTB, or in other words, associations between the supplement of trace elements and decreased risk of PTB, including Fe (17)(18)(19)(20)(21) , Cu (22) , Zn (21,23,24) , Se (25)(26)(27)(28) and Sr (24) . However, some studies have revealed that the intake of trace elements were significantly associated with increased risk of PTB, including Fe (29)(30)(31) , Cu (31)(32)(33)(34)(35) and Zn (35)(36)(37) . In addition, other others have found no association between the levels of these elements and PTB, including Fe (24,33,38) , Cu (24,37,38) , Zn (31)(32)(33)39) , Se (21,(31)(32)(33)37,38,40) , Sr (31,35,38) and Mo (24,…”

“…However, some studies have revealed that the intake of trace elements were significantly associated with increased risk of PTB, including Fe (29)(30)(31) , Cu (31)(32)(33)(34)(35) and Zn (35)(36)(37) . In addition, other others have found no association between the levels of these elements and PTB, including Fe (24,33,38) , Cu (24,37,38) , Zn (31)(32)(33)39) , Se (21,(31)(32)(33)37,38,40) , Sr (31,35,38) and Mo (24,31,32,38) . Thus far, previous studies examining the association between prenatal exposure to essential trace minerals and PTB have yielded inconsistent results, and most of them have focused on overall PTB.…”

“…Thus far, previous studies examining the association between prenatal exposure to essential trace minerals and PTB have yielded inconsistent results, and most of them have focused on overall PTB. Several studies have classified PTB and analysed SPTB separately, but the sample size is relatively small (20,21,(31)(32)(33)37) .…”