[Effects of Low-dose Antibiotic Exposure on Fetal Growth and Development]

Objective To analyze maternal blood exposure to non-therapeutic antibiotics in late pregnancy and explore the effects of low-dose antibiotics on fetal growth and development.Methods A total of 104 pregnant women in late pregnancy (28-32 weeks) without serious pregnancy complications were enrolled,who had regular antenatal examination and delivery in Peking Union Medical College Hospital and did not use therapeutic antibiotics 2 months before pregnancy and in the whole pregnant process.The levels of antibiotics in the maternal blood were detected by liquid chromatography-tandem mass spectrometry,and the pregnant women were assigned into an antibiotic exposure group (antibiotic positive) and a non-exposure group (antibiotic negative).The length,weight,placental weight,and placental volume of the newborns in the two groups were measured,and the data were statistically analyzed by t test or χ test.Results The maternal blood antibiotic test showed 7 positive cases (6.73%,antibiotic exposure group) and 97 negative cases (93.27%,non-exposure group). The average length of newborns in the antibiotic exposure group and the non-exposure group was (49.57±1.40) cm and (48.85±1.77) cm,respectively,with no significant difference (t=1.060,P=0.363).The average weight of newborns in the antibiotic exposure group and the non-exposure group was (3558.57±382.95) g and (3275.36±356.41) g,respectively,with significant difference (t=2.021,P=0.046).The mean placental weight in the antibiotic exposure group and the non-exposure group was (676.43±124.59) g and (631.96±129.25) g,respectively,with no significant difference (t=0.881,P=0.380).The mean placental volume in the antibiotic exposure group and the non-exposure group was (724.67±174.91) cm³ and (676.82±220.86) cm³,respectively,with no significant difference (t=0.560,P=0.388).Compared with those in the non-exposure group,the neonatal length,neonatal weight,placental weight,and placental volume in the antibiotic exposure group increased by 1.47%,8.65%,7.04%,and 7.07%,respectively.Conclusion There are antibiotics in the environment,and maternal blood exposure to non-therapeutic antibiotics can promote the growth and development of the fetus and placenta,especially increasing the fetal weight.