Cesarean Section Rate in Singleton Primiparae and Related Factors in Beijing, China

Background： The cesarean section rate （CSR） bas been a main concern worldwide. The present study aimed to investigate the CSR in Beijing, China, and to analyze the related lactors of CS delivery. Methods： An observational study was conducted in 15 medical centers in Beijing using a systemic cluster sampling naethod. In total, 15, 194 pregnancies were enrolled in the study between ,lune 20, 2013 and November 30, 2013. Independent t-tests and Pearson＇s Chi-square test were nsed to examine differences between two groups, and related factors of the CSR were examined by multivariable logistic regression. Results： The CSR was 41.9% （4471/10,671） in singleton primiparae. Women who were more than 35 years old had a 7.4-fold increased risk of CS delivery compared with women 〈25 years old （odd ratio [OR] 7.388, 95% confidence interval [Cl] = 5.561-9.816, P 〈 0.001 ）. Prepregnancy obese women had a 2-1bid increased risk of CS delivery compared with prepregnancy normal weight women （OR = 2.058. 95% CI = 1.640-2.584, P〈 0.001 ）. The excessive weight gain group had a 1.4-fold increased risk of CS delivery compared with the adequate weight gain group （OR 1.422, 95% CI = 1.289 1.568, P〈 0.001 ）. Gestational diabetes mellitus （GDM） women and DM women had an increased risk of CS delivery （ 1.2- and 1.7-fold, respectively） compared with normal blood glucose women. Women who were born in rural areas had a lower risk of CS delivery than did those who were born in urban areas （OR 0.696, 95% CI = 0.625-0.775, P 〈 0.001 ）. The risk of CS delivery gradually increased with a decreasing education level. Neonates weighing 3000-3499 g had the lowest CSR （36.2%）. Neonates weighing 〈2500 g had a 2-fold increased risk of CS delivery compared with neonates weighing 3000 3499 g （OR - 2.020, 95% CI=1.537 2.656, P 〈 0.001 ）. Neonates weighing ≥4500 g had an 8.3-fold increased risk of CS delivery compared with neonates weighing 3000-3499 g （OR = 8.313.95% CI= 4.436-15.579, P 〈 0.001）. Conclusions： Maternal age, prepregnancy body mass index, geslational weight gain, blood glncose levels, residence, education level, and singleton fetal birth weight arc all factors that might significantly affect the CSR.

Association between Maternal Weight Indicators and Iron Deficiency Anemia during Pregnancy： A Cohort Study

Background： The effect of maternal weights on the risk of iron deficiency anemia （IDA） during pregnancy remains unclear. The study aimed to investigate the association between maternal weight indicators and IDA during pregnancy. Methods： We conducted a cohort study to examine the association between maternal weight indicators, including prepregnancy body mass index and the rate of gestational weight gain （GWG）, and the risk of IDA among Chinese pregnant women. Data about new-onset IDA at different trimesters from a national cross-sectional survey were collected; information regarding baseline variables and rate of GWG from women participating in the survey were retrospectively collected. Tested IDA and reported IDA were documented. Multilevel logistic regression to examine the association between maternal weight indicators and the risk of IDA after adjusting for potential confounders was conducted. Results： This study enrolled 11,782 pregnant women from 24 hospitals from September 19, 2016, to November 20, 2016. Among those, 1515 （12.9%） IDA events were diagnosed through test （test IDA）： 3915 （33.3%） were identified through test and patient reporting （composite IDA）. After adjusting for confounders and cluster effect of hospitals, underweight pregnant women, compared with normal women, were associated with higher risk of test IDA （adjusted odds ratio [aOR]： 1.35, 95% confidence interval [CI]： 1.17-1.57 and composite IDA （aOR： 1.35, 95% CI： 1.21-1.51）; on the contrary, overweight and obese women had lower risk of test IDA （aOR： 0.68, 95% CI： 0.54-0.86 overweight; aOR： 0.30, 95% CI： 0. 13-0.69 obese） and composite IDA （aOR： 0.77, 95% （71：0.67-0.90 overweight; aOR： 0.34, 95% CI： 0.21-0.55 obese）. The higher rate of GWG was associated with higher risk of IDA （test aOR： 1.86 95% CI： 1.26-2.76; composite aOR： 1.54, 95% CI： 1.16-2.03）. Conclusions： Pregnant women who are underweight betbre pregnancy and who have taster GWG are more likely to develop IDA. Enforced weight control during pregnancy and use of iron supplements, particularly among underweight women, may be warranted.