The interactions between maternal iron supplementation and iron metabolism-related genetic polymorphisms on birth outcomes: a prospective study in Chinese.

There were significant interactions between maternal iron supplementation and rs7385804 (P=0.009), rs149411 (P=0.035), rs4820268 (P=0.031), the unweighted GRS (P=0.018), and the weighted GRS (P=0.009) on birth weight. Compared with FA supplementation only, FA + iron supplementation significantly increased birth weight among women with more effect alleles in rs7385804 (β: 88.8 g, 95% CI: 9.2, 168.3) and the GRSs (the highest unweighted GRS: β 135.5 g, 95% CI: 7.7, 263.4; the highest weighted GRS: β 145.9 g, 95% CI: 43.4, 248.5); it had a trend of decreasing birth weight and increasing low birth weight risk among women with fewer effect alleles. results CONCLUSION: In our population, maternal genetic background related to iron metabolism plays a significant role in determining the efficacy of iron supplementation. Routine iron supplementation could be more beneficial to fetal weight growth among mothers with higher genetic risk for low iron/hemoglobin status.