Search

Introduction Immigrants from Western industrialized countries are rarely found in immigrant studies. Our primary objective was to calculate the rate of cesarean delivery, 5-min Apgar score <7, and preterm birth among Chinese and Western women. Our secondary objective was to examine whether there are significant differences in terms of risk factors between Western immigrants who chose to deliver in their country of citizenship compared to those who chose to deliver in China. Methods Single-center retrospective cohort study in Shanghai, China. Multivariate logistic regression models used delivery outcome, and place of delivery (China vs. country of citizenship) as outcome variables. Results Preterm birth occurred at a rate of 3.82% among Chinese citizens, 4.12% among Chinese-born Western citizens, and 6.54% among non-Chinese-born Western citizens. After adjustment, preterm birth <37 weeks was more frequent among non-Chinese-born Western citizens compared with Chinese citizens, with an odds ratio of 1.82 (Confidence Interval 1.20-2.78), p = 0.005. Variables statistically associated with giving birth in China were maternal age ≥35 years and being Chinese-born Western, as well as the absence of medical or obstetrical conditions. Discussion Western immigrants have overall good obstetrical outcomes in China, and this could be partly explained by selective immigration, but also by the Salmon bias, as women with risk factors tend to return to their country of citizenship for the delivery. However, the preterm birth rate was higher among Western women than in their Chinese counterparts, and further research is needed. [ABSTRACT FROM AUTHOR]

Objective:With China's rapid economic growth in the past 3 decades, an increase in rate of macrosomia has been reported in China. Fetal growth is a result of multiple factors including genetic potential for growth, maternal nutrition, maternal metabolism, endocrine factors and placental perfusion and function. However, the detailed mechanism of how macrosomia happened remains poorly known. Recent studies showed that the expression of a number of microRNAs (miRNAs) in placentas is involved in fetal growth. We hypothesized that aberrant expression of microRNA-21 (miR-21) and microRNA-16 (miR-16) in placenta is associated with macrosomia.Study design:Using quantitative real time PCR, we analyzed the expression level of miR-21 and miR-16 in terminal placentas of macrosomia pregnancies (n=35) and normal controls (n=35). Potential target genes of miRNA were predicted using TargetScan, miRanda and PicTar. Target genes were mapped to KEGG pathways using KEGG Mapper with an in-house Perl script with KEGG Gene IDs.Result:MiR-21 showed significant up-regulation in macrosomia (P=0.037). After controlling the potential confounders, multivariable logistic regression analysis suggested the risk of macrosomia increased, multivariable adjusted ORs of macrosomia for those in the highest tertile was 3.931 (95%CI: 1.049-14.736) compared with those in the lowest tertile in terms of miR-21 level. The target genes of miR-21 were involved in eight possible signaling pathways. They were pathways in P53 signaling pathway, MAPK signaling pathway, HIF-1 signaling pathway, TGF-beta signaling pathway and PI3K-Akt signaling pathway (P<0.001), Wnt signaling pathway, Jak-STAT signaling pathway and mTOR signaling pathway (P<0.05).Conclusion:Our study is the first to investigate the association between placental miRNA expression and macrosomia. Our results indicate that the expression level of miR-21 in placental tissue may be involved in the development of macrosomia. [ABSTRACT FROM AUTHOR]