Rare earth element in maternal hair does not heighten risk of neural tube defects
Rare earth element (REE) accumulation in maternal hair do not significantly increase the risk of neural tube defects (NTD) in the offspring, a new study has found.
The study included 452 pregnant women, of which 191 had NTD-affected pregnancies (cases) and 261 had healthy offspring (controls). All participants underwent face-to-face interviews where baseline information on sociodemographic factors, supplementation and other pregnancy details were collected.
All participants provided hair samples, which were then subjected to plasma-mass spectrometry to measure the concentrations of REE including lanthanum (La), cerium (Ce), praseodymium (Pr) and neodymium (Nd).
Of the 191 cases, 85 had anencephaly, 79 had spina bifida, 24 had encephalocele and three had unknown NTD subtypes. Cases were significantly more likely to have a history of birth defects (p=0.001) and have fever or flu during early pregnancy (p<0.001).
The most abundant REE in the maternal hair samples was La, with a detection rate of 78 percent. This was followed by Ce (75 percent), Pr (73 percent) and Nd (72 percent). Median concentrations of La, Ce and Nd were higher in cases than in controls, but the differences did not reach statistical significance.
In contrast, median Pr concentrations were significantly higher in cases and in the anencephaly subgroup than in controls.
Among all the REEs and all the NTD subtypes, only the concentration of Pr was significantly associated with a higher risk of encephalocele (univariate odds ratio, 3.00; 95 percent CI, 1.15 to 7.80; p<0.05). After adjusting for maternal age, supplements, previous birth defects, education and other potential confounders, none of the REE concentrations were associated with risk of any of the NTD subtypes.