Study on the determinants of intrauterine growth restriction / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the intrauterine growth retardation (IUGR) and its determinants so as to provide evidence for maternal and child health care programs to be carried out.</p><p><b>METHODS</b>Fourteen townships were selected by cluster random sampling from 37 townships in Liuyang. A total of 6 105 pregnant women who had established their health care programs during April 2008 and March 2011, were recruited in this study. Records on pregnancy care manual and delivery were collected. 6 105 single live births were divided into two groups (IUGR group and control group). Those whose birth weight was below the 10th percentile for mean weight corrected for gestation age were grouped as IUGR group. Chi-square test and Multivariate logistic Regression method were used to estimate the determinants of IUGR.</p><p><b>RESULTS</b>A total of 6 105 women, pregnant with a singleton gestation were enrolled in the study: 528 of these pregnancies were complicated with IUGR (8.65%). Data from the multivariate logistic regression analysis showed that maternal age less than 25 (OR = 1.268), prim parity (OR = 1.706), BMI less than 18.5 kg/m² at first obstetrical examination (OR = 1.709), deficiency in weight gain during pregnancy (OR = 1.576) and pregnancy-induced hypertension syndrome (OR = 1.698) were related risk factors to intrauterine growth retardation.</p><p><b>CONCLUSION</b>Maternal age, prim parity, BMI, weight gain during pregnancy and pregnancy-induced hypertension syndrome were factors associated to the intrauterine growth retardation. Effective measures in reducing the intrauterine growth retardation should include factors as monitoring maternal weight and the change of weight during pregnancy in order to maintain the weight at normal ranges. Prevention and therapy for pregnancy-induced hypertension syndrome, should also be strengthened.</p>

Study on the influence of pregnancy-induced hypertension on neonatal birth weight and its interaction with other factors / 中华流行病学杂志

<p><b>OBJECTIVE</b>To research the influence of pregnancy-induced hypertension (PIH) on neonatal birth weight and its interaction with other factors.</p><p><b>METHODS</b>A retrospective cohort study was conducted in this study. 14 townships were randomly selected by cluster random sampling method from 37 townships in Liuyang city, Hunan province. All pregnant women from these 14 townships with pregnancy care manual and delivery record, during April 1st, 2008 to March 31st, 2011 were selected as subjects of this study. Blood pressure during pregnancy and neonatal birth weight were recorded. Multinomial logistic regression model was used to adjust the confounding factors. Addictive effects model was used for interaction analysis.</p><p><b>RESULTS</b>Data from 6 102 subjects were collected, including 418 (6.9%) pregnant women with PIH, 166 (2.7%) infants with low birth weight and 333 (5.5%) with fetal macrosomia. Results from the Multinomial logistic regression analysis showed significant association between neonatal birth weight and PIH, premature birth, BMI <18.5 before pregnancy, and weight gain ≥ 16 kg during pregnancy. Data from the Interaction analysis showed that there was strong positive interactions between PIH and premature birth to low birth weight infants (RERI = 35.08, API = 0.435, S = 1.7), and between PIH and BMI<18.5 before pregnancy to low birth weight infants. However, no significant interaction was found between PIH and weight gain.</p><p><b>CONCLUSION</b>Factors as PIH, premature birth, BMI before pregnancy and weight gain showed impact on low birth weight or fetal macrosomia. PIH also showed significant interaction on neonatal birth weight with premature birth as well as BMI before pregnancy, respectively.</p>

A population based study on incidence and determinants of preterm birth in Liuyang Hunan / 中南大学学报(医学版)

OBJECTIVE@#To describe the incidence and to discuss the risk factors of premature birth in rural areas of Liuyang.@*METHODS@#We collected subjects from villages and towns in Liuyang through cluster sampling method. Before enrolling in this cohort, all of them had established health records from January 2010 to December 2011. We followed up the early, middle and late stages of pregnancy until delivery, and collected medical records and maternal health care manual of this cohort as our data materials. We explored the main influence factors of premature delivery by χ2 test and unconditional logistic regression analysis for single factor and multivariate analysis.@*RESULTS@#Among 6270 women who enrolled in our cohort, 259 were diagnosed as premature birth. The incidence (4.13%) was lower than the national average level. Non-conditional logistic regression analysis showed that the risk factors of premature birth were as follows: OR of placental abruption was 7.678 (95% CI: 2.249-26.215), that of premature rupture of fetal membranes (PROM) was 5.177 (95% CI: 3.945-6.793), that of uterine abnormal and deformity was 2.675 (95% CI: 1.007-7.107), that of placenta anomaly was 2.633 (95% CI: 1.666-4.162), that of hypertension in pregnancy was 2.172 (95% CI: 1.044-4.521), that of pregnancy complications was 1.806 (95% CI: 1.033-3.157), that of male fetus was 1.429 (95% CI: 1.086-1.881). Protective factors of preterm birth were too frequent prenatal examination (OR=0.502, 95% CI: 1.033-3.157) and single pregnancy (OR=0.155, 95% CI: 0.075-0.319).@*CONCLUSION@#Preterm delivery is caused by complicated factors, such as placental abruption, PROM and male fetus. Comprehensive measures should be taken to reduce preterm birth.

Pre-conception factors for intrauterine growth retardation / 中南大学学报(医学版)

OBJECTIVE@#To analyze the pre-conception factors for intrauterine growth retardation.@*METHODS@#A nested case-control study was conducted in a cohort of 1368 women from 14 Child and Maternity Health Care Departments by cluster sampling method in Liuyang City, Hunan Province. Following-up until delivery, we collected their medical records and maternal health care manual materials. All neonates with intrauterine growth retardation were detected in the follow-up (the case group) and another 186 neonates without intrauterine growth retardation, matched with gender and mother's age, were randomly selected from the cohort as controls. χ2 test and multiple conditional logistic regression were used to investigate the determinants of intrauterine growth retardation.@*RESULTS@#Intrauterine growth retardation was associated with BMI (OR=64.775), waist circumference (OR=0.166), abortion (OR=6.997), level of total cholesterol (OR=0.045), folic acid (OR=0.077), and cortisol (OR=9.164).@*CONCLUSION@#Intrauterine growth retardation is associated with BMI, waist circumference, abortion,level of total cholesterol, folic acid, and cortisol. Effective measures to reduce intrauterine growth retardation in children include strengthening the detection of pre-pregnancy blood biochemical indicators to guide health care during pregnancy, and increasing nutrition during pregnancy according to pre-pregnancy BMI and waist circumference.

A pre-conception cohort to study preeclampsia in China: Rationale, study design, and preliminary results / 中南大学学报(医学版)

OBJECTIVE@#It is uncertain whether preeclampsia (PE) is caused by pre-existing factors or by pregnancy itself. We want to answer this important question in public health by conducting a large pre-conception cohort in China.@*METHODS@#A prospective and pre-conception cohort study with a target recruitment of 5000 couples who plan to have a baby within 6 months was performed and their conception, delivery, and postpartum were followed up in Liuyang county, Hunan Province of P. R. China.@*RESULTS@#A total of 1915 young couples have been recruited into this unique pre-conception cohort till now. In general, both systolic blood pressure and diastolic blood pressure decreased in early second trimester from pre-conception level but increased in third trimester and at delivery.@*CONCLUSION@#The proposed pre-conception cohort study will have important theoretical and practical implications on the prevention of PE and its associated cardiovascular disease risks.

Secular trends in trial of labor and associated neonatal mortality and morbidity in the United States, 1995 to 2002 / 中南大学学报(医学版)

OBJECTIVE@#A proportion of elective repeated cesarean sections where a trial of labor in a uterus with a previous scar was not attempted is on the increase. This study aimed to assess how reduced the use of trial of labor has impacted on neonatal outcomes in the United States.@*METHODS@#Pregnant women with one previous cesarean delivery and a singleton live birth of the index pregnancy were abstracted from the 1995 to 2002 birth registration data of the United States. Adjusted odds ratios for adverse neonatal outcomes of trial of labor were estimated by multiple logistic regression models, in overall study subjects and in the two periods with high and low rates of trial of labor.@*RESULTS@#A total of 1833407 eligible subjects were included in the analysis. Rate of trial of labor after one previous cesarean section dropped from 38.5% in 1995 to 15.0% in 2002. No significant change was observed in the patient population profile. Successful vaginal birth after cesarean delivery (VBAC) also declined from 76.6% in 1995 to 66.0% in 2002. A trial of labor after one previous cesarean section was correlated with increased risks of asphyxia-related neonatal death and neonatal morbidity. This risk was even more pronounced in low risk women and in the last study years with the lowest rate of trial of labor.@*CONCLUSION@#The reduced use of trial of labor after one cesarean delivery in recent years in the United States has actually resulted in increased risk of adverse neonatal outcomes associated with a trial of labor.

Association between posttraumatic stress disorder and preflood behavioral characteristics among children aged 7-15 years in Hunan, China

To explore the relationship between posttraumatic stress disorder [PTSD] and preflood behavioral characteristics among children aged 7-15 years in Hunan, China. In 2000, a retrospective study was carried out among children who had been exposed to the 1998 floods in Hunan. A multistage sampling method was used to select subjects from the flood-affected areas. A structured questionnaire administered to the children selected was used to diagnose PTSD based on the DSM-IV criteria. A parent questionnaire was used to measure preflood behavioral characteristics related to health, behavioral, and habit problems. The association between PTSD and preflood behavioral characteristics was assessed using chi[2]-tests and multivariate logistic regression. A total of 7,038 children from 13,450 households, aged 7-15 years, were investigated. The overall prevalence of PTSD was 2.05%. Generally, the PTSD-positive rate increased with increasing scores for behavioral characteristics. Preflood behavioral characteristics are an important factor influencing the prevalence of PTSD among children exposed to floods. It is therefore necessary to give special attention to children with behavioral problems in order to reduce the psychological impact of floods

Prevalence and risk factors for childhood obesity in Changsha and Shenzhen in China / 中南大学学报(医学版)

Objective To determine the prevalence and the risk factors for childhood obesity in Changsha and Shenzhen, China.Methods A case-control study was conducted in 209 obese children (the cases) identified in the investigation on childhood obesity in 6 288 children aged 6 to 9 years in Changsha and Shenzhen in China and 209 children with normal weight (the controls). The cases and controls were matched by gender, age, and school. Adjusted odds ratio (aOR) and 95% confidence intervals (CI) for the risk factors were measured.Results The prevalence rate of overweight and obese children was 9.28% and 3.30% in Changsha, and 12.17% and 4.22% in Shenzhen, respectively. The rate of overweight children is significantly higher in Shenzhen than in Changsha. No statistical difference was observed in the rate of obesity between the children in both cities. Paternal obesity (OR 1.78, 95% CI 1.01 to 3.16), maternal weight gain during pregnancy ≥15.0 kg (OR 5.22, 95% CI 2.78 to 9.80), birth weight ≥4.00 kg (OR 2.55, 95% CI 1.24 to 5.26), unhealthy snacks ≥1 per week (OR 3.94, 95% CI 1.11 to 13.99), and watching television ≥2 hours per day(OR 2.35, 95% CI 1.01 to 5.47) were associated with childhood obesity when potential confounding factors were adjusted by multi-variable logistic regression analysis. Conclusion Paternal obesity, gestational weight gain, high birth weight, and unhealthy life-style are important risk factors for obesity in urban children in south China.