孕前体重指数、孕期体重增加与新生儿窒息的关系

目的 了解孕前体重指数(BMI)、孕期体重增加与新生儿窒息发生危险的关系.方法 数据来自"中美预防出生缺陷和残疾合作项目"中嘉兴地区的围产保健监测数据库.研究对象为1995-2000年在嘉兴地区参加婚前/孕前体检且分娩单胎活产儿孕满20周的83 030名孕产妇.运用χ2检验或趋势χ2检验比较不同BMI组或其他特征人群新生儿窒息发病率的差别,利用多元logistic回归分析孕前BMI、孕期体重增加与新生儿窒息发生危险之间的关系.结果 新生儿窒息发病率为11.3%(95% CI:11.1%～11.6%).新生儿窒息发病率从BMI＜18.5 kg/m2组的11.0%(95% CI:10.5%～11.5%)逐渐升至BMI≥25.0 kg/m2组的12.9%(95% CI:11.6%～14.4%),自孕期体重增加＜0.3 kg/wk的12.4%(95% CI:11.9%～13.0%)逐渐降至≥0.5 kg/wk的10.6%(95% CI:10.1%～11.0%).孕前BMI≥25.0 kg/m2组的新生儿重度窒息发生率高于BMI更低组.在调整了地区、年龄、文化程度、职业、产次、产前检查次数、孕期高危因素、产时高危因素、孕周和出生体重后,以BMI＜18.5 kg/m2组为参照组,BMI为18.5～22.9 kg/m2、23.0～24.9 kg/m2和≥25.0 kg/m2组发生新生儿窒息的OR值分别为1.03(95% CI:0.97～1.09)、1.06(95% CI:0.96～1.16)和1.14(95% CI:1.00～1.31).进一步调整孕期增重后,上述OR值分别为1.02(95% CI:0.95～1.09)、1.01(95% CI:0.90～1.13)和1.08(95% CI:0.92～1.28).以孕期体重增加≥0.5 kg/wk组作为参照,孕期体重增加为0.3～kg/wk和＜0.3 kg/wk组发生新生儿窒息的OR值分别为1.06(95% CI:1.01～1.12)和1.09(95% CI:1.02～1.20).结论 孕期体重增加＜0.5 kg/wk加大新生儿窒息发生的危险,提示临床上宜对妇女孕前的BMI进行监测,并据此进行孕前指导和孕期管理,以保持合理的孕期体重,降低新生儿窒息的发生危险.     

体质指数与总死亡率关系的Meta分析

目的采用Meta分析方法定量综合国内外前瞻性研究中不同水平体质指数(body mass index,BMI)与总死亡率关系。方法以体质指数、超重、肥胖、死亡率、队列研究、前瞻性研究及随访研究为主题词和关键词联合检索PubMed和中国期刊网全文数据库(CNKI),查找相关文献。合格的文献限定于探讨普通人群BMI与总死亡率关系的前瞻性研究,BMI分组数≥6,且报道了各组死亡的相对危险度(RR)及95%可信区间(95%CI)。结果共纳入32篇文献,含54个队列研究(总人数:7 910 932人,死亡数:1 376 997人)。男女合并发现,BMI和总死亡风险呈U形关系,总死亡风险最低时的BMI为23.0~24.9 kg/m2。与此对照,其他BMI组总死亡风险RR(95%CI)分别为:<18.5 kg/m2:1.53(1.49~1.57);18.5~20.9 kg/m2:1.09(1.07~1.11);21.0~22.9 kg/m2:1.06(1.04~1.08);25.0~26.9 kg/m2:1.01(1.00~1.03);27.0~29.9 kg/m2:1.11(1.10~1.12);30.0~34.9 kg/...     

孕前体重指数及其孕期增加对妊娠结局的影响

目的:定量评价孕前体重指数及孕期体重指数增加情况对我国北方孕妇妊娠结局的影响。方法:收集2007～2009年在沈阳3家医院分娩的3741名单胎妊娠初产妇,按照孕前体重指数(BMI)分为4组:低体重组(BMI18.5kg/m2)、正常体重组(18.5kg/m2≤BMI24kg/m2)、超重组(24kg/m2≤BMI28kg/m2)和肥胖组(BMI≥28kg/m2)。按照孕期BMI增加情况分为3组:A组(BMI增加4)、B组(BMI增加4～6)、C组(BMI增加6)。Logistic回归评估不良妊娠结局的危险度,结果用RR和95%CI表示。结果:①和正常体重组相比,孕前低体重、超重和肥胖组的孕妇患子痫前期的RR分别为0.53(95%CI0.29～0.97)、2.84(95%CI2.05～3.94)和5.35(95%CI3.47～8.49);患妊娠期糖尿病的RR分别为0.35(95%CI0.16～0.78)、3.40(95%CI2.44～4.75)和4.95(95%CI2.91～7.06);剖宫产和出生大于胎龄儿(LGA)的风险也随孕前体重的增加而增加。②和B组相比,C组增加了子痫前期(RR1.85,95%CI1.40～2.44)、妊娠期糖尿病(RR1.39,95%CI1.05～1.86)、剖宫产(RR1.37,95%CI1.15～1.63)及出生LGA(RR1.98,95%CI1.44～2.73)的相对危险性,但降低了出生SGA的风险。A组降低了子痫前期、剖宫产和出生LGA的风险,但增加了早产(34周)和出生SGA的风险。结论:孕前体重指数过高及孕期体重指数增加过度可以明显增加孕妇子痫前期、妊娠期糖尿病和剖宫产的风险。应加强健康教育,适度控制孕期体重,合理营养减少肥胖,对预防妊娠并发症,改善妊娠结局是有必要的。     

妊娠前体重与早产危险性的关系

目的:评估妊娠前体重对早产危险性的影响。方法:根据产前及分娩监护数据,选取2002~2007年在该院连续分娩符合标准的孕妇9 246例,并根据妊娠前BMI分为低体重组(BMI<18.5 kg/m2)、正常体重组(BMI 18.5~24.9 kg/m2)、超重组(BMI 25~29.9 kg/m2)、肥胖组(BMI≥30 kg/m2)。分析各组早产率,评价孕前体重对早产危险性的影响。结果:低体重组妊娠后早产的发生率为(22.9%),早产率和危险性均高于其他各组(RR=2.90,P<0.05)。肥胖组早产率为8.8%,早产危险性与正常体重组相似(P>0.05),但高于超重组(P<0.05)。结论:妊娠前BMI较低者孕期发生早产的危险性增加。     

孕中期血红蛋白水平与妊娠高血压疾病的关系

目的 分析孕中期血红蛋白水平(Hb)与孕晚期妊娠高血压疾病(PIH)之间的关系. 方法 比较1995～2000年浙江省和江苏省4个县(市)单胎分娩的95 620例妇女孕中期不同Hb水平孕妇的PIH发病率;采用loglstic回归模型控制年龄、职业、文化程度、产次和体质指数(BMI)等因素后,估计Hb水平与PIH之间的关联程度. 结果 孕晚期及产时孕妇PIH的发病率为9.7%;Hb水平为100～109 g/L时,PIH的发病率最低;Hb水平升高或者降低,PIH的发病率均呈增加趋势,Hb<80 g/L的孕妇PIH的发病风险增加79%(OR=1.79,95%CI:1.29～2.49),Hb≥150 g/L的孕妇PIH的发病风险增加47%(OR=1.47,95%CI:1.00～2.21). 结论 孕中期Hb水平与PIH的发生风险之间呈"U"型关系,重度贫血以及高水平Hb都可能会增加PIH的发生风险.     

妊娠前体质指数及其增幅与计划妊娠产妇不良妊娠的关系

目的 研究妊娠前体质指数(BMI)及其增幅与计划妊娠产妇不良妊娠的关系.方法 回顾性分析2017年4月-2018年4月杭州市富阳区第一人民医院收治的236例计划妊娠产妇的临床资料,依据孕前BMI将其分为低体质组58例(BMI＜18.5 kg/m2)、健康组62例(18.5 kg/m2≤ BMI＜24.9 kg/m2)、...     

单胎妊娠期孕妇足月时增重的临床范围研究

目的探讨单胎妊娠孕妇孕期适宜体质量增加范围。方法选择2009年1月-2013年10月在云南省大理州人民医院进行产前检查并分娩足月单胎活产的糖代谢正常孕妇3 892例作为研究对象。按美国医学研究院(IOM)2009年制定的不同孕前体质指数(BMI)标准分为3组:以BMI18.5 kg/m2定义为低BMI组;BMI18.5~24.9 kg/m2定义为正常BMI组;BMI≥25.0 kg/m2定义为高BMI组。新生儿出生体质量≥4 000 g为巨大儿;出生体质量2 500 g为低出生体质量儿;出生体质量2 500~4 000 g为正常出生体质量儿;以正常出生体质量2 500~4 000 g为适宜出生体质量。对各组孕妇资料进行统一录入,并进行回顾性分析。结果 3组孕妇中,低出生体质量儿的发生率均较低,其中低BMI组的发生率最高为2.39%,明显高于正常BMI组的0.70%(P0.01)。而三组中巨大儿的发生率却随着孕前BMI的增加而升高,其中高BMI组最高为8.87%,明显高于正常BMI组和低BMI组(P均0.01)。将2 500~4 000 g作为适宜新生儿出生体质量,通过百分位法计算出孕前低BMI、正常BMI及高BMI孕妇的适宜体质量增加范围分别为13.5~18.0 kg、12.5~16.5 kg和8.5~14.0 kg。以此范围为标准,将3 892例孕妇分为低于范围组、符合范围组和高于范围组,采用多分类Logistic回归分析法对母婴并发症风险进行评估结果显示,低于适宜体质量增加范围的孕妇分娩低出生体质量儿的风险有升高趋势(OR=2.86,95%CI为1.79~4.54,P=0.022),符合适宜体质量增加范围组的孕妇剖宫产风险降低(OR=0.09,95%CI为0.04~0.20,P0.01),高于适宜体质量增加范围组的孕妇发生妊娠期高血压疾病的风险升高(OR=4.81,95%CI为1.95~11.87,P0.01),剖宫产风险升高(OR=8.83,95%CI为2.76~28.25,P0.01),分娩巨大儿的风险也有所升高(OR=9.01,95%CI为1.01~81.76,P0.05)。结论我国单胎妊娠妇女孕前BMI18.5 kg/m2者孕期适宜体质量增加范围为13.5~18.0 kg,孕前BMI为18.5~24.9 kg/m2者孕期适宜体质量增加范围为12.5~16.5 kg,孕前BMI≥25.0 kg/m2者孕期适宜体质量增加范围为8.5~14.0 kg。     

口腔癌与体质指数关系的病例-对照研究

目的探讨口腔癌与体质指数(BMI)的关系。方法用病例-对照研究法,对口腔癌206例与对照组584例进行调查。用PASW V18软件包logistic回归分析数据,计算口腔癌发病风险的调整比值比(OR)。结果与正常BMI组(18.5~23.9kg/m2)相比,低BMI组(18.5kg/m2)的OR=2.02(95%CI=1.13~3.59),高BMI组(≥24kg/m2)OR=0.39(95%CI=0.26~0.57)。结论低BMI是口腔癌的危险因素。     

老年人群体质指数与心血管疾病危险因素相关性分析

目的探究老年人群体质指数(BMI)与心血管疾病危险因素发病风险之间的关系,为老年人体重管理和肥胖干预提供参考依据。方法选取2015年1-7月在温州医科大学附属第一医院进行体检的1 140名老年人为研究对象,男性511名,女性629名,年龄60岁,进行1年的跟踪随访。对调查对象进行问卷调查(人口学特征、生活方式及既往病史等)、体格检查,并测定空腹血糖、血脂。患有糖尿病、高血压及血脂异常3种疾病中的1种及以上定义为有心血管疾病危险因素。按照世界卫生组织推荐的亚洲人群BMI分类标准,将调查对象分为低体重(BMI18.5 kg/m_2),体重正常(18.5kg/m_2≤BMI≤22.9 kg/m_2),超重(23.0 kg/m_2≤BMI≤24.9 kg/m_2),肥胖I级(25.0 kg/m_2≤BMI≤29.9 kg/m_2)和肥胖II级(BMI≥30.0 kg/m_2)。用SPSS 19.0软件进行t检验,χ2检验。BMI与心血管疾病危险因素之间关系采用多因素logistic回归分析。结果在老年人群中,男性、女性至少有1种心血管疾病危险因素的检出率分别为62.8%和73.9%。logistic回归分析结果显示,在调整年龄、肌力、吸烟、饮酒、运动锻炼、肝脏疾病和肾脏疾病后,与正常体重者相比,低体重者心血管疾病危险因素发病风险OR值为1.57(95%CI:1.09~2.26),超重、肥胖I级和肥胖II级老年人心血管疾病危险因素发病风险OR值分别为1.49(95%CI:0.94~2.02)、3.21(95%CI:2.28~4.52)和4.12(95%CI:2.23~7.60)。结论老年人群BMI与心血管疾病危险因素的发病风险之间存在"U"形关系。低体重的老年人患心血管疾病的危险性增加。随着肥胖程度的增加,老年人患心血管疾病的危险性上升。     

孕期体重增长与巨大儿发生的随访数据分析研究

目的分析孕妇孕期体重增长对巨大儿发生的影响,为合理管理孕期体重提供参考依据。方法利用我国5个省区县监测点的孕妇孕晚期及儿童满月随访数据,招募孕晚期孕妇并填写孕晚期调查问卷,前瞻观察至孕妇分娩满1个月并填写新生儿满月调查问卷,问卷中儿童分娩孕周、出生体重、性别信息主要通过摘录医疗记录获取;根据是否发生巨大儿分为巨大儿组(192例)和对照组(2 405例),最终采用病例对照研究设计方法进行分析。采用χ~2检验或Fisher确切概率法比较两组差异,采用多因素Logistic回归模型分析孕期增重与巨大儿发生的关系;以孕前BMI为分层因素,进一步分析孕期增重与巨大儿发生的关系。结果本研究共随访孕产妇2 731例,随访率为100%。经数据清洗后纳入分析2 597例。控制孕妇年龄、孕妇文化程度、家庭年收入、妊娠期糖尿病、分娩孕周、新生儿性别协变量后,孕妇孕前超重或肥胖(OR=2.43, 95%CI:1.65～3.56)、孕期增重过多(OR=2.18, 95%CI:1.46～3.27)是巨大儿发生的独立危险因素;以孕前BMI为分层因素,进一步分析显示:孕前BMI正常(18.5 kg/m~2≤BMI 24.9 kg/m~2)的孕妇孕期增重过多(OR=2.07, 95%CI:1.27～3.37)、孕前超重或肥胖(BMI≥25.0 kg/m~2)的孕妇孕期增重过多(OR=2.63, 95%CI:1.07～6.47)均会增加巨大儿发生风险。结论孕期增重过多是巨大儿发生的独立危险因素,孕前体重正常但孕期增重过多,以及孕前超重或肥胖的人群孕期增重过多均会增加巨大儿发生的危险。     

Body mass index and subsequent risk of hypertension, diabetes and hypercholesterolemia in a population-based sample of Japanese

OBJECTIVE: To clarify relationships between BMI (body mass index) and the incidence of hypertension, diabetes and hypercholesterolemia among a community-based sample. METHOD: A 4.3-year follow-up study was conducted of 1,427 men and women aged 40-69 to examine the relationships between BMI (kg/m2) and the incidence of hypertension, diabetes and hypercholesterolemia. RESULTS: During the follow-up, there were 118 cases of incident hypertension diagnosed, 56 of diabetes and 136 of hypercholesterolemia. After adjusting for sex, age, cognitive physical activity, food intake, alcohol intake, smoking, and blood pressure level, blood glucose level and serum total cholesterol level at the baseline, excess risks with the BMI category of > or = 27.0 versus 21.0-22.9 were found for hypertension [relative risk (95% CI) = 1.9(1.0-3.6)] and diabetes [2.9(1.2-7.4)]. However, no excess risk was evident for the 23.0-24.9 or 25.0-26.9 categories. Multivariate relative risks (95%CI) of hypercholesterolemia compared with the BMI category of 21.0-22.9 were 1.5 (0.9-2.6) for 23.0-24.9, 1.7(0.9-3.2) for 25.0-26.9 and 1.6 (0.8-3.1) for > or = 27.0, none of which reached statistical significance. When we combined all three diseases, the relative risks (95%CI) compared with the BMI category of 21.0-22.9 were 0.9(0.6-1.5) for 23.0-24.9, 1.2(0.7-2.1) for 25.0-26.9 and 1.8 (1.0-3.3) for > or = 27.0. CONCLUSIONS: Increased risks of hypertension, diabetes and lifestyle-related disease were only evident with the BMI category > or = 27.0. Education for weight reduction should be less emphasized for persons with a BMI of 25.0-26.9 than for these with a value of > or = 27.0.     

Body mass index, waist circumference, and risk of coronary heart disease: a prospective study among men and women

OBJECTIVE: The purpose of the study was to assess the risk of CHD associated with excess weight measured by BMI and waist circumference (WC) in two large cohorts of men and women. DESIGN, SETTING, SUBJECTS: Participants in two prospective cohort studies, the Health Professionals Follow-up Study (N = 27,859 men; age range 39-75 years) and the Nurses' Health Study (N = 41,534 women; 39-65 years) underwent 16-year follow-up through 2004. RESULTS: 1,823 incident cases of CHD among men and 1,173 cases among women were documented. Compared to men with BMI 18.5 to 22.9 kg/m2, those with a BMI > 30.0 kg/m2 had a multivariate-adjusted RR of CHD of 1.81 (95% CI 1.48 - 2.22). Among women, those with a BMI > 30.0 kg/m2 had a RR of CHD of 2.16 (95% CI 1.81 - 2.58). Compared to men with a WC < 84.0 cm, those with WC of greater than 102.0 cm had a RR of 2.25 (95% CI 1.77 - 2.84). Among women, the RR of CHD was 2.75 (95% CI 2.20 - 3.45) for those with WC of greater than 88.0 cm. CONCLUSIONS: In these analyses from two large ongoing prospective cohort studies, both BMI and WC strongly predicted future risk of CHD. Furthermore, WC thresholds as low as 84.0 cm in men and 71.0 cm in women may be useful in identifying those at increased risk of developing CHD. The findings have broad implications in terms of CHD risk assessment in both clinical practice and epidemiologic studies.     

Risk factors differ between recurrent and incident preeclampsia: a hospital-based cohort study

PurposeTo examine whether risk factors, including prepregnancy body mass index (BMI), differ between recurrent and incident preeclampsia.MethodsData included electronic medical records of nulliparas (n = 26,613) delivering 2 times or more in Utah (2002–2010). Modified Poisson regression models were used to examine (1) adjusted relative risks (RR) of preeclampsia and 95% confidence intervals (CI) associated with prepregnancy BMI; (2) maternal risk factor differences between incident and recurrent preeclampsia among primiparous women.ResultsIn the first pregnancy, compared with normal weight women (BMI: 18.5–24.9), preeclampsia risks for overweight (BMI: 25–29.9), obese class I (BMI: 30–34.9), and obese class II/III (BMI: ≥35) women were 1.82 (95% CI = 1.60–2.06), 2.10 (95% CI = 1.76–2.50), and 2.84 (95% CI = 2.32–3.47), respectively, whereas second pregnancy–incident preeclampsia risks were 1.66 (95% CI = 1.27–2.16), 2.31 (95% CI = 1.67–3.20), and 4.29 (95% CI = 3.16–5.82), respectively. Recurrent preeclampsia risks associated with BMI were highest among obese class I women (RR = 1.60; 95% CI = 1.06–2.42) without increasing in a dose-response manner. Nonwhite women had higher recurrence risk than white women (RR = 1.70; 95% CI = 1.16–2.50), whereas second pregnancy–incident preeclampsia risk did not differ by race.ConclusionPrepregnancy BMI appeared to have stronger associations with risk of incident preeclampsia either in the first or second pregnancy, than with recurrence risk. Nonwhite women had higher recurrence risk.     

Obesity and associated coronary heart disease risk factors in a population of low-income African-American and white women: the North Carolina WISEWOMAN project

BACKGROUND: Obesity has been associated with many co-occurring coronary heart disease (CHD) risk factors as well as CHD mortality. These associations have been shown to vary between African-American and white sample populations. METHODS: The authors examined whether obesity co-occurs with several CHD risk factors (diabetes, hypertension, hypercholesterolemia, low high-density lipoprotein cholesterol (HDL-C)), and estimated the 10-year risk for CHD in the North Carolina WISEWOMAN (Well Integrated Screening and Evaluation for Women Across the Nation) study sample. This sample includes low-income African-American and white women (> or = 50 years of age). RESULTS: Among white women (n = 1,284), 34% were overweight (BMI = 25.0-29.99 kg/m(2)) and 35% obese (BMI > or = 30 kg/m(2)); among African-American women (n = 754), 28% were overweight and 59% obese. Among obese and nonobese African-American women, the prevalence of three or more co-occurring risk factors was similar (obese = 17.7% (95% confidence interval (CI): 13.9, 21.6) and nonobese = 13.3% (95% CI: 8.7, 17.8)). By contrast, the prevalence among white women was greater among the obese (26.9% (95% CI: 22.9, 31.0)) than the nonobese (13.0% (95% CI: 9.7, 16.2)). CONCLUSIONS: The differences between and within African-American and white women may be accounted for by the high levels of HDL-C among obese and nonobese African-American women.     

Maternal obesity and the risk of infant death in the United States

BACKGROUND: Maternal obesity (defined as prepregnancy body mass index [BMI] >or=30 kg/m) is associated with increased risk of neonatal death. Its association with infant death, postneonatal death, and cause-specific infant death is less well-characterized. METHODS: We studied the association between maternal obesity and the risk of infant death by using 1988 US National Maternal and Infant Health Survey data. A case-control analysis of 4265 infant deaths and 7293 controls was conducted using SUDAAN software. Self-reported prepregnancy BMI and weight gain were used in the primary analysis, whereas weight variables in medical records were used in a subset of 4308 women. RESULTS: Compared with normal weight women (prepregnancy BMI = 18.5-24.9 kg/m) who gained 0.30 to 0.44 kg/wk during pregnancy, obese women had increased risk of neonatal death and overall infant death. For obese women who had weight gain during pregnancy of <0.15, 0.15 to 0.29, 0.30 to 0.44, and >or=0.45 kg/wk, the adjusted odds ratios of infant death were 1.75 (95% confidence interval = 1.28-2.39), 1.42 (1.07-1.89), 1.59 (1.00-2.51), and 2.87 (1.98-4.16), respectively. Nonobese women with very low weight gain during pregnancy also had a higher risk of infant death. The subset with weight information from medical records had similar results for recorded prepregnancy BMI and weight gain. Maternal obesity was associated with neonatal death from pregnancy complications or disorders relating to short gestation and unspecified low birth weight. CONCLUSIONS: Maternal obesity is associated with increased overall risk of infant death, mainly neonatal death.     

Weight, height, and body mass index and risk for ovarian cancer in a cohort study

PURPOSE: Reported associations between ovarian cancer and body size are inconsistent. We assessed ovarian cancer and anthropometry in the Breast Cancer Detection Demonstration Project Follow-Up Study. METHODS: The 46,026 participants completed a baseline interview and mailed questionnaires between 1979 and 1998. By using multiple sources, we identified 346 incident ovarian cancers during follow-up. We calculated rate ratios (RRs) and 95% confidence intervals (CIs) to estimate relative risks for developing ovarian cancer associated with height and weight (measured 1973 to 1980) and self-reported current and usual adult weight (collected during follow-up). RESULTS: Neither taller height (> or =66 versus <62 inches; RR, 0.90; 95% CI, 0.64-1.26) nor greater weight (> or =161 versus < or =120 lbs; RR, 1.09; 95% CI, 0.77-1.55) was associated with ovarian cancer. Compared with normal weight (body mass index [BMI], 18.5 to 24.9 kg/m(2)), overweight (BMI, 25 to 29.9 kg/m(2); RR, 1.00; 95% CI, 0.78-1.29) and obesity (BMI, 30 to 34.9 kg/m(2); RR, 0.94; 95% CI, 0.59-1.48) were not associated with ovarian cancer. Severe obesity (BMI > or = 35 kg/m(2)) produced a nonsignificantly elevated RR (1.55; 95% CI, 0.84-2.84). Associations with histologic types and statistical interactions with menopausal status and hormone therapy use were null. CONCLUSIONS: Based on height and weight measured before baseline, overweight and obesity were not significantly associated with ovarian cancer in this cohort.     

Low preconception body mass index is associated with birth outcome in a prospective cohort of Chinese women

Low maternal prepregnancy BMI is associated with adverse birth outcomes, but the BMI at which risk increases is not well defined. We assessed whether the relationship between prepregnancy BMI and birth outcomes is influenced by the extent to which mothers were underweight in a prospective study in Anhui, China. The women (n = 575) were 20-34 y old, married, nulliparous and nonsmokers. All measures of infant growth increased with increasing maternal BMI until a plateau was reached at a BMI of 22-23 kg/m2. Infants born to the 27% of women who were severely underweight before pregnancy (BMI < or = 18.5 kg/m2) were at increased risk for fetal growth deficits associated with infant morbidity. Compared with a normal BMI, being severely underweight was associated with mean (+/- SEM) reductions of 219 +/- 40 g in infant birthweight and 6.7 +/- 1.3% in the birthweight ratio and an 80% increase in risk of intrauterine growth restriction [odds ratio (OR) 1.8; 95% CI: 1.0, 3.3; P = 0.05]. Being severely underweight was also associated with smaller infant head circumference and lower ponderal index. Being moderately underweight (18.5 < BMI < 19.8 kg/m2) was not significantly associated with adverse pregnancy outcomes. Gestational age and risk of preterm birth were not associated with maternal BMI. More than half of the women in this study were underweight before pregnancy. Although being moderately underweight was not associated with increased risk of adverse pregnancy outcomes, being severely underweight was an important risk factor for reduced fetal growth.     

Body mass index and stroke incidence in Japanese community residents: The Jichi Medical School (JMS) Cohort Study

Background

High body mass index (BMI) has been reported as a risk factor for cardiovascular events in Western countries, while low BMI has been reported as a risk factor for cardiovascular death in Asian countries, including Japan. Although stroke is a major cause of death and disability in Japan, few cohort studies have examined the association between BMI and stroke incidence in Japan. This study aimed to examine the association between BMI and stroke incidence using prospective data from Japanese community residents.