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Obesity has been increasing worldwide. Data on obesity status among men of reproductive age are scarce. This study aimed to assess the national prevalence and trend of overweight and obesity among reproductive-age men in rural China. In the nationwide population-based study, data were obtained from the National Free Preconception Health Examination Project in rural China from 2010 to 2014. Weight and height were measured in 16 161 982 men aged 15–49 years and their female partners (15 997 739 participants aged 15–49 years) before conception, and body mass index (BMI) was calculated. We found that the prevalence of combined overweight and obesity among men was 33.8% (33.7–33.9%) according to Chinese criteria (BMI ≥ 24.0 kg/m2), the corresponding rates of obesity were 6.3% (6.2–6.4%; BMI ≥ 28.0 kg/m2), respectively. The prevalence varied in different ethnic groups, geographic regions, age, education and GDP levels, and increasing trend was observed over the 5-year study period. In addition, 45.8% of couples had at least one of them as overweight or obesity. About one third of men aged 15–49 years before conception in rural China are overweight or obese. Overweight/obesity clusters in families, which highlights the importance of family involvement of early prevention of obesity in China.

BackgroundDiabetes mellitus (DM) increases the risk of adverse maternal and neonatal outcomes, and optimization of glycemic control during pregnancy can help mitigate risks associated with diabetes. However, studies seldom focus precisely on maternal blood glucose level prior to pregnancy. We aimed to evaluate the associations between preconception blood fasting plasma glucose (FPG) level and subsequent pregnancy outcomes.Methods and findingsWe conducted a population-based retrospective cohort study among 6,447,339 women aged 20–49 years old who participated in National Free Pre-Pregnancy Checkups Project and completed pregnancy outcomes follow-up between 2010 and 2016 in China. During the preconception health examination, serum FPG concentration was measured, and self-reported history of DM was collected. Women were classified into three groups (normal FPG group: FPG < 5.6 mmol/L and no self-reported history of DM; impaired fasting glucose [IFG]: FPG 5.6–6.9 mmol/L and no self-reported history of DM; and DM: FPG ≥ 7.0 mmol/L or self-reported history of DM). The primary outcomes were adverse pregnancy outcomes, including spontaneous abortion, preterm birth (PTB), macrosomia, small for gestational age infant (SGA), birth defect, and perinatal infant death. Logistic regression model was used to calculate odds ratio (OR) and 95% confidence interval (CI) after adjusting for confounding variables. The mean age of women was 25.24 years, 91.47% were of Han nationality, and 92.85% were from rural areas. The incidence of DM and IFG was 1.18% (76,297) and 13.15% (847,737), respectively. Only 917 (1.20%) women reported a history of DM (awareness of their DM status), of whom 37.28% (337) had an elevated preconception FPG level (≥ 5.6 mmol/L), regarded as noncontrolled DM. A total of 1,005,568 (15.60%) women had adverse pregnancy outcomes. Compared with women with normal FPG, women with IFG had higher risks of spontaneous abortion (OR 1.08; 95% CI 1.06–1.09; P < 0.001), PTB (1.02; 1.01–1.03; P < 0.001), macrosomia (1.07; 1.06–1.08; P < 0.001), SGA (1.06; 1.02–1.10; P = 0.007), and perinatal infant death (1.08; 1.03–1.12; P < 0.001); the corresponding ORs for women with DM were 1.11 (95% CI 1.07–1.15; P < 0.001), 1.17 (1.14–1.20; P < 0.001), 1.13 (1.09–1.16; P < 0.001), 1.17 (1.04–1.32; P = 0.008), and 1.59 (1.44–1.76; P < 0.001). Women with DM also had a higher risk of birth defect (OR 1.42; 95% CI 1.15–1.91; P = 0.002). Among women without self-reported history of DM, there was a positive linear association between FPG levels and spontaneous abortion, PTB, macrosomia, SGA, and perinatal infant death (P for trend <0.001, <0.001, <0.001, 0.001, <0.001). Information about hypoglycemic medication before or during pregnancy was not collected, and we cannot adjust it in the analysis, which could result in underestimation of risks. Data on 2-hour plasma glucose level and HbA1c concentration were not available, and the glycemic control status was evaluated according to FPG value in women with DM.ConclusionsWomen with preconception IF...

ObjectiveUnhealthy maternal weight before pregnancy increases the risk of various adverse pregnancy outcomes. We conducted a nutrition survey to provide baseline data on the prepregnant nutritional status of mothers in order to better understand the association between prepregnancy maternal body mass index (BMI) and adverse pregnancy outcomes.DesignA large, prospective, population-based cohort study.SettingData from the National Free Preconception Health Examination Project (NFPHEP) in China during 2010–2012.Participants536 098 pregnant women out of 2 120 131 were evaluated.Primary and secondary outcome measuresThe primary adverse pregnancy outcomes included preterm birth (PTB), low birth weight (LBW), spontaneous miscarriage (SM), ectopic pregnancy (EP) and stillbirth (SB). A χ2 test was used to compare the prevalence of each BMI category during 2010–2012. Univariable and multiple logistic regression analyses were performed to assess the association between prepregnancy BMI and various adverse pregnancy outcomes.ResultsBetween 2010 and 2012, the average BMI decreased from 21.31 to 21.16, while underweight prevalence increased from 10.40% to 14.14%. An age-stratified subgroup analysis indicated that the underweight prevalence increased from 13.52% to 17.02% among women aged 21–24 and from 10.72% to 13.71% among women aged 25–34. Overweight prevalence increased from 9.84% to 10.75% (25–34 years) and from 17.10% to 19.20% (35–49 years). Obesity prevalence increased from 2.17% to 2.42% and from 4% to 4.2% among women aged 25–34 and 35–49 respectively. Prepregnancy underweight was associated with PTB, LBW and SM; overweight women had an increased risk of LBW; obese women had a higher risk of LBW, SM, EP and SB.ConclusionsWhile the average prepregnancy BMI decreased, the prevalence of underweight individuals in a very large population significantly increased. The abnormal prepregnancy BMIs were associated with increased risks of adverse pregnancy outcomes. Most notably, underweight prepregnant women appeared to be at a greater risk of developing adverse pregnancy outcomes in China's rural areas.

IMPORTANCE Airborne particulate matter pollution has been associated with preterm birth (PTB) in some studies. However, most of these studies assessed only populations living near monitoring stations, and the association of airborne particulate matter having a median diameter of 1 μm or less (PM 1) with PTB has not been studied. OBJECTIVE To evaluate whether PM 1 concentrations are associated with the risk of PTB. DESIGN, SETTING, AND PARTICIPANTS This national cohort study used National Free Preconception Health Examination Project data collected in 324 of 344 prefecture-level cities from 30 provinces of mainland China. In total, 1 300 342 healthy singleton pregnancies were included from women who were in labor from