Smoking during pregnancy and preterm birth according to obstetric history: French national perinatal surveys

The relation between smoking and preterm delivery is not totally known. Our aim was to determine whether smoking during pregnancy was associated with preterm birth among women at different risk according to their obstetric history. The study was based on data from the 1998 French national perinatal survey. Of the 13073 singleton live births, 4.7% were preterm; 15% of the pregnant women were moderate (one to nine cigarettes per day) and 10% heavy smokers (at least 10 cigarettes per day). Smoking heavily was related to preterm birth (crude odds ratio [OR] = 1.35, 95% confidence interval [95% CI]: [1.04, 1.74]). Multivariable logistic regression showed a relation between smoking and preterm birth among multiparae without previous adverse pregnancy outcomes; the associated adjusted ORs (AORs) were 1.25 [95% CI 0.83, 1.87] among moderate smokers and 1.46 [95% CI 0.98, 2.20] among heavy smokers. The corresponding AORs were 0.69 [95% CI 0.46, 1.05]) and 0.96 [95% CI 0.59, 1.56] for primiparae and 1.11 [95% CI 0.63, 1.93] and 0.50 [95% CI 0.25, 0.98] for multiparae with previous adverse pregnancy outcomes. Our study showed a relation between heavy smoking during pregnancy and preterm birth mostly for women with low obstetric risk.     

The influence of maternal age on very preterm birth of twins: differential effects by parity

For singleton births, parity can modify the effect of maternal age on birth outcomes such as low birthweight and preterm birth; however, it is unknown whether this relationship exists for twin births. As the rate of twin births increases among older women, it is important to understand how parity may influence the relationship between maternal age and adverse birth outcomes. The NCHS Matched Multiple Birth Data Set, which contains all twin births in the USA from 1995 to 1998, was analysed. Parity was grouped into two levels (primiparous--no prior live births, and multiparous--at least one prior live birth), and maternal age was divided into the following groups: 20-24, 25-29, 30-34, 35-39, and 40 years or more. Very preterm birth was defined as births occurring before 33 weeks. Logistic regression was used to obtain odds ratios (OR) to estimate the risk of very preterm birth, and to determine the relationships between parity, maternal age, and very preterm birth. Among primiparae, women 40 years and older had a reduced risk of very preterm birth compared with women of 25-29 years (OR 0.74 [95% CI=0.66, 0.84]). Among multiparae, women 40 years and older had the same risk of very preterm birth compared with women of 25-29 years (OR 1.00 [95% CI=0.90, 1.12]). However, stratification by education revealed that the age gradient was limited to women with >12 years education among primiparae. The effect of maternal age on very preterm birth of twins differs according to parity. To some extent, that effect is further modified by education. Therefore, future analyses of maternal age and twin birth outcomes should account for measures of obstetric history and other factors, which may influence these results.     

Socio-economic factors associated with preterm delivery. Results of the European project in Spain

Objectives: The objectives of this paper were to analyse the effect of social, personal and medical risk factors on preterm birth (moderate versus very preterm) or on two preterm birth groups (spontaneous versus indicated).Methods: Results from the Spanish collaborating centre of the European multicentre case-control study EUROPOP (European Program of Occupational Risks and Pregnancy Outcome) are presented. All preterm births (529) between 22 and 36 completed weeks of amenorrhea and 788 births of 37 or more completed weeks of amenorrhea (control group) are included. Explicative variables are divided in social, personal and medical factors. A univariate and multivariate analysis by means of a logistic regression were carried out.Results: Very preterm birth risk was higher for women over 34 years, adjusted OR: 2.53 (1.42-4.52), with lower educational level, adjusted OR: 1.79 (1.07-2.98), for primigravid women or multigravid women with only first trimestre abortion, adjusted OR: 1.86 (1.13-3.04), and for multigravid women with previous preterm birth or second trimestre abortion, adjusted OR: 5.53 (2.97-10.35). A similar trend was observed for moderate preterm birth. Probability of spontaneous preterm birth was higher for mother over 34 years, adjusted OR: 1.51 (1.01-2.26), with lower income, adjusted OR: 1.75 (1.07-2.88) and for multigravid women with previous preterm birth or second trimestre abortion, adjusted OR: 2.96 (1.86-4.71). Results were similar for indicated preterm birth.Conclusion.: Social differences were found to be related to moderate and very preterm birth. No differences were observed between risk factors and kind of preterm birth: spontaneous or indicated.     

Previous abortion and the risk of low birth weight and preterm births

OBJECTIVE: To investigate the association between previous abortion and low birth weight (LBW) and preterm birth (PB). METHOD: The study examined live, singleton births using data from the United States Collaborative Perinatal Project. Logistic regression was used to control for obstetric and medical history, and lifestyle and demographic factors. RESULT: Compared with women with no history of abortion, women who had one, two and three or more previous abortions were 2.8 (95% CI 2.48 to 3.07), 4.6 (95% CI 3.94 to 5.46) and 9.5 (95% CI 7.72 to 11.67) times more likely to have LBW, respectively. The risk for PB was also 1.7 (95% CI 1.52 to 1.83), 2.0 (95% CI 1.73 to 2.37) and 3.0 (95% CI 2.47 to 3.70) times higher for women with a history of one, two and three or more previous abortions, respectively. CONCLUSION: Previous abortion is a significant risk factor for LBW and PB, and the risk increases with the increasing number of previous abortions. Practitioners should consider previous abortion as a risk factor for LBW and PB.     

中国10县(市)1993-2005年单胎儿早产流行状况研究

目的描述中国10县（市）单胎儿早产流行状况及长期变化趋势。方法资料来源于“中美预防出生缺陷和残疾合作项目”中的围产保健监测数据库。研究对象为3省10县（市）在1993—2005年间所有孕满28周且分娩单胎儿（包括死胎死产）的孕产妇542923名，计算早产率并描述其分布特征。结果1993—2005年间在10县（市）共发生早产25784例（其中死胎死产1530例），早产率为4，75％（95％CI：4.69～4.81），活产儿早产率为4．49％（95％CI：4．44～4．55）。单胎早产率呈逐年下降趋势，无明显季节倾向；南方城市、南方农村和北方农村的早产率依次降低；分娩年龄与早产率呈“U”型关系；文化程度低、孕产次多、有早产史或自然流产史者早产率较高。结论10县（市）单胎早产率呈逐年下降趋势，不同地区差别显著。     

Smoking during pregnancy according to obstetric complications and parity: results of the EUROPOP study

This study aimed to analyse the relationship between smoking and preterm birth (22-36 weeks) according to the main obstetric complications leading to the preterm birth, both overall and by parity. The EUROPOP study is a case-control study carried out between 1994 and 1997; 3,787 preterm and 5,602 full-term births were included, from maternity units in 10 countries, using the same protocol. Social, demographic and medical information was collected after delivery, from obstetric records and interviews with the mothers. Cases were classified according to the main obstetric complication (hypertension, haemorrhage, preterm premature rupture of membranes (PPROM), idiopathic spontaneous preterm labour, intrauterine growth retardation, all other causes). Multiple logistic regression analysis was used to control for confounders. Twenty four percent of cases and 20% of controls were smokers. Smoking during pregnancy, heavy smoking (>or=10 cigarettes per day) in particular, was a risk factor for preterm birth (aOR = 1.39, 95% CI:1.20-1.60). Smoking increased the risk of preterm delivery due to all obstetric complications other than hypertension. For these complications, the risk of preterm delivery associated with smoking was higher for multiparae (aOR = 1.46, 95% CI:1.24-1.71) than for primiparae (aOR = 1.18, 95% CI:1.00-1.38). In conclusion, smoking during pregnancy increases the risk of preterm birth among women with all obstetric complications except hypertension. This association is stronger in multiparae than in primiparae and the risk is higher for heavy smokers.     

Spontaneous abortions and birth defects related to tap and bottled water use, San Jose, California, 1980-1985.

We recently studied pregnancies occurring during 1980-1985 in four study areas in Santa Clara County, California. Two of the areas were exposed to solvent-contaminated drinking water during 1980 and 1981, and two were unexposed. There was an overall excess of spontaneous abortions among women who reported any tapwater consumption during the first trimester of pregnancy compared with those who reported no tapwater consumption [odds ratio (OR) = 4.0; 95% confidence interval (CI) = 1.8-9.1)], regardless of exposure to the contaminated water. The odds ratio for spontaneous abortion for women reporting any vs no tapwater was 6.9 (95% CI = 2.7-17.7) after adjustment for numerous potential confounders using multiple logistic regression analyses. The elevated odds ratio of spontaneous abortion was seen among tapwater drinkers who used no filters or softener-type filters but not among women who reported use of active filters. Spontaneous abortion rates were reduced in women who reported any vs no bottled water consumption (OR = 0.26; 95% CI = 0.16-0.43). Among women who reported no tapwater consumption, no birth defects occurred among 263 live births; in comparison, among women who reported tapwater consumption, 4% of 908 live births had defects (P = 0.0001). We observed no relation between birth defects and bottled water use.     

The Association between Having a Preterm Birth and Later Maternal Mental Health: An Analysis of U.S. Pregnancy Risk Assessment Monitoring System Data

IntroductionAlthough previous studies have found a relationship between having a preterm birth and maternal depression, methodologic issues may have limited the generalizability of results. Thus, the purpose of this study was to evaluate the relationship between having a preterm birth and postpartum depressive symptoms using a large, population-based sample of U.S. women.MethodsThis secondary data analysis used 2012–2014 U.S. Pregnancy Risk Assessment Monitoring System data (N = 89,366). Data on the exposure, preterm birth, were obtained from birth certificates. Infants born at 32 to less than 37 weeks' gestation were considered moderate to late preterm, infants born at 28 to less than 32 full weeks' gestation were considered very preterm, and infant born at less than 28 full weeks’ gestation were considered extremely preterm. To assess the outcome, two Pregnancy Risk Assessment Monitoring System questions measuring postpartum depressive symptoms were used. Logistic regression was used to calculate unadjusted and adjusted odds ratios (ORs) and 95% confidence interval (CIs).ResultsAfter adjustment for confounders, the relationship between having a preterm birth and maternal hopelessness was statistically significant for those who had very preterm and extremely preterm births (moderate to late preterm OR, 1.19; 95% CI, 1.00–1.42; very preterm OR, 1.28; 95% CI, 1.04–1.58; extremely preterm OR, 1.81; 95% CI, 1.31–2.49). In addition, after adjustment, findings indicated no association between preterm birth and maternal loss of interest (extremely preterm OR, 0.85 95% CI, 0.60–1.19; very preterm OR, 1.04; 95% CI, 0.86–1.26; preterm OR, 0.95; 95% CI, 0.82–1.10).ConclusionsGiven the statistically significant increased association between having a preterm birth and postpartum depressive symptoms, health professionals may consider implementing comprehensive screening for depression and other mental illnesses among women who give birth prematurely. Findings may also inform future interventions to emphasize the importance of postpartum care among women who have experienced preterm birth.     

Neighborhood Socioeconomic Status in Relation to Preterm Birth in a U.S. Cohort of Black Women

This study examines the association between neighborhood socioeconomic status (SES) and preterm birth among U.S. Black women. A composite variable for neighborhood SES, derived from 7 U.S. Census Bureau indicators, was assessed in relation to self-reported preterm birth (505 spontaneous and 452 medically indicated) among 6,390 women in the Black Women’s Health Study who delivered singleton births during 1995–2003. The odds ratio (OR) for preterm birth, comparing the lowest (most deprived) to the highest (least deprived) quartiles of neighborhood SES, was 0.98 (95 % CI, 0.80, 1.20) after adjustment for individual-level characteristics. Low neighborhood SES was not associated with spontaneous or medically indicated preterm birth overall or within strata of maternal age, education, or geographic region. The only significant finding was higher odds of medically indicated preterm birth associated with low neighborhood SES among unmarried women. Low neighborhood SES was not materially associated with preterm birth in this study of U.S. Black women.     

Healthy worker effect and pregnancy: role of adverse obstetric history and social characteristics.

Data from a survey conducted in 1981 on a national sample of 5508 births in France were used to analyse the role of a history of previous adverse pregnancy outcome (spontaneous abortion, perinatal death or adverse fetal condition) in the selection mechanisms of women with regard to occupational activity, and the impact on the relation between work and preterm delivery. The study, carried out separately in each parity group, showed that occupational activity was associated with a more favourable outcome for women of parity one: the preterm delivery rate was significantly higher among women who had never worked than among those who continued working during pregnancy. However, the hypothesis of a "healthy worker effect" linked to a history of adverse obstetric outcome was not confirmed in this study. A selection effect of women from a history of spontaneous abortions was observed, but these were not linked to preterm delivery. Among multiparous women, a history of perinatal death or adverse fetal condition did not seem to modify women's behaviour towards their work. Selection mechanisms of women towards occupational activity according to sociodemographic factors were also analysed and showed that the higher percentage of younger women among those who had never worked explained the higher rate of preterm delivery in that group.     

Trends in preterm births in Flanders, Belgium, from 1991 to 2002

Changes in the preterm birth rate have been attributed predominantly to increases in multiple pregnancies, associated with advanced maternal age and assisted reproduction, and to obstetric intervention. We examined their contribution to the frequencies of preterm (<37 weeks), very preterm (<32 weeks) and severely preterm (<28 weeks) birth among 700 383 singleton and twin births in Flanders from 1991 to 2002. We examined changes across four 3‐year periods (triennia) with confidence interval [CI] analysis and yearly incremental rates using linear and logistic regression analyses. Over the 12 years, twin pregnancies increased from 1.5% to 2.0%, averaging 1.6% [95% CI 1.54, 1.66] in 1991–93 and 1.9% [95% CI 1.81, 1.94] in 2000–02 (P < 0.001). The proportion of women aged 35 years or more increased from 6.8% [95% CI 6.69, 6.92] in 1991–93 to 11.3% [95% CI 11.2, 11.5] in 2000–02 (P < 0.001) and those aged under 20 from 1.9% [95% CI 1.81, 1.93] to 2.3% [95% CI 2.26, 2.41] (P < 0.001). Assisted reproduction increased from 2.6% [95% CI 2.48, 2.62] to 4.2% [95% CI 4.11, 4.30] (P < 0.001) and obstetric intervention to end pregnancy from 36.2% [95% CI 36.0, 36.4] to 40.3% [95% CI 40.1, 40.6] (P < 0.001). These increases related to an annual increase of 0.23% in the preterm birth rate from 5.5% [95% CI 5.4, 5.6] in 1991–93 to 7.2% [95% CI 7.1, 7.3] in 2000–02 (P < 0.001). The proportions of very and severely preterm births also increased by nearly a third, but their contribution to the total preterm birth rate remained stable at 15% and 5%, respectively. Odds ratios for the increases per year were 1.035 [95% CI 1.032, 1.038] for preterm birth, 1.024 [95% CI 1.018, 1.031] for very preterm and 1.028 [95% CI 1.017, 1.040] for severely preterm births after adjusting for other changes in the population. Overall, the data show, first, marked increases in the frequency of known contributors to the preterm birth rate, including twin pregnancies, advanced maternal age, assisted reproduction and obstetric intervention. Second, the preterm birth rate further increased significantly within subgroups of women with one or more of these characteristics. Third, the preterm birth rate also rose, from 4.4% [95% CI 4.2, 4.5] in 1991–93 to 5.6% [95% CI 5.5, 5.8] in 2000–02 (P < 0.001), in women with none of these contributing factors. This indicates that changes in the frequency of these known predictors are insufficient to explain the steady increase in preterm, very preterm and severely preterm births over more than a decade.     

Adverse reproduction outcomes among employees working in biomedical research laboratories

OBJECTIVES: The aim of the study was to investigate reproductive outcomes such as birthweight, preterm births, and postterrm births among women working in research laboratories while pregnant. METHODS: Female university personnel were identified from a source cohort of Swedish laboratory employees, and the database was linked to the medical birth register. The first births of the women were included in the analysis, 249 pregnancies among the women with laboratory work and 613 pregnancies among the women without laboratory tasks. Information about exposure to various laboratory agents was obtained from a previous questionnaire investigation at the research group level according to a specific definition. The ponderal index and ratio between observed and expected birthweights were calculated. Logistic regression models were used for analyses of dichotomous outcomes (preterm, postterrm and birthweight). RESULTS: Exposure to laboratory work with solvents was associated with an increased risk of preterm births, the estimated odds ratio (OR) being 3.4 (1.0 < 95% confidence interval < 11.9). An association with work with bacteria was also observed for postterm births (OR 2.7, 1.0 < or = 95% confidence interval < 7.4). CONCLUSIONS: There was a slightly elevated risk for some reproductive outcomes among the women working with certain laboratory tasks, specifically for preterm and postterm births in relation to work with solvents and bacteria.     

Influence of smoking and snuff cessation on risk of preterm birth

The mechanisms by which antenatal smoking exposure increases the risk of preterm birth remain unknown. Swedish oral moist snuff contains quantities of nicotine comparable to those typically absorbed from cigarette smoking, but does not result in exposure to the products of combustion, for example carbon monoxide. In a nation-wide study of 776,836 live singleton births in Sweden from 1999 to 2009, the authors used multiple logistic regression models to examine associations between cessation of smoking and Swedish snuff use early in pregnancy and risk of preterm birth (before 37 weeks). Compared with non-tobacco users both before and in early pregnancy, the adjusted odds ratios (OR), 95% confidence interval (CI) were OR=0.92, 95% CI 0.84-1.01, for women who stopped using snuff, and OR=0.90, 95% CI 0.87-0.94, for women who stopped smoking. In contrast, continued snuff use and smoking were associated with increased risks of preterm birth (adjusted OR=1.29, 95% CI 1.17-1.43, adjusted OR=1.30, 95% CI 1.25-1.36, respectively). The snuff and smoking-related risks were, if anything, higher for very (before 32 weeks) than moderately (32-36 weeks) preterm birth, and also higher for spontaneous than induced preterm birth. These findings suggest that antenatal exposure to nicotine is involved in the mechanism by which tobacco use increase the risk of preterm birth.     

Value of multinomial model in epidemiology: application to the comparison of risk factors for severely and moderately preterm births

BACKGROUND: The multinomial logistic regression model is employed to model the relationship between an outcome variable with more than two categories and a set of covariates. This model is not widely used in epidemiology. We discuss the value of the multinomial model by comparing it with the binary logistic model, and we present a statistical comparison of odds ratios (OR) using the multinomial model. We studied the associations between obstetric history and very (< 33 weeks of amenorrhea) and moderate (33-36 weeks) preterm births. METHODS: Parameters (lnOR) of very and moderate preterm births, associated with the severity of obstetric history (none=0, moderate=1, severe=2), were estimated using two logistic binary models (moderate preterm births vs full-term births (>=37 weeks), and very preterm births vs full-term births) and one logistic multinomial model which compared very and moderate preterm births to full-term births. These analyses were performed before and after adjustment for a covariate: the country of survey. Parameters of very preterm birth and moderate preterm birth, estimated from multinomial model, were compared using Wald test. These analyses were performed using data from a large case-control survey in Europe, the EUROPOP survey; 1 675 very preterm births, 3 652 moderate preterm births and 7 965 full-term births were included. RESULTS: Crude parameters of very and moderate preterm births were similar, regardless the logistic regression model, binary or multinomial. The estimated parameters slightly differ after adjustment for the covariate, but lower variance estimates were obtained using multinomial logistic regression model. Parameters of very preterm birth associated with moderate obstetric history, B(gp)=0.5040, and severe obstetric history, B(gp)'=1.545, differ significantly from those of moderate preterm birth, B(pm)=0.4434 and B(pm)'=1.223 respectively (p < 0.001). CONCLUSION: Parameters obtained in separate logistic binary models are close to those obtained in a multinomial model. The multinomial model is useful for testing the heterogeneity of risk factors for distinct health problems.     

早产影响因素的前瞻性队列研究

目的 分析中国早产的流行现状及危险因素,为早产的预防提供参考依据.方法 本研究数据来源于中国孕产妇队列研究.协和项目(Chinese Pregnant Women Cohort Study,CP-WCS),通过问卷调查和医院信息系统(hospital information system,HIS)收集孕妇基本情况和分娩...     

Chemical hair treatments and adverse pregnancy outcome among Black women in central North Carolina

Several studies suggest that toxic chemicals in hair products may be absorbed through the scalp in sufficient amounts to increase the risks of adverse health effects in women or their infants. This case-control study of 525 Black women from three counties in North Carolina who had delivered a singleton, liveborn infant examined whether exposure to chemicals used in hair straightening and curling increased the odds that the infant was preterm or low birth weight. Cases consisted of 188 preterm and 156 low birth weight births (for 123 women, their infant was both low birth weight and preterm). Controls were 304 women who delivered term and normal birth weight infants. Women who used a chemical hair straightener at any time during pregnancy or within 3 months prior to conception had an adjusted odds ratios (OR) of 0.7 (95% confidence interval (CI) 0.4-1.1) for preterm birth and 0.6 (95% CI 0.4-1.1) for low birth weight. Exposure to chemical curl products was also not associated with preterm delivery (adjusted OR = 0.9, 95% CI 0.5-1.8) or low birth weight (adjusted OR = 1.0, 95% CI 0.5-1.9). Despite this failure to find an association, continued search for risk factors to which Black women are uniquely exposed is warranted.     

Abortion and its effect on risk of preeclampsia and transient hypertension

We examined the effect of abortion type, number, and gestational age on the risk of preeclampsia and transient hypertension among women who received prenatal care from 13 obstetric practices in southern Connecticut between April 1988 and December 1991 (N = 2,739). Subjects were interviewed before 16 weeks' gestation regarding reproductive history and pregnancy-related risk factors. We estimated the risk of preeclampsia (N = 44) and transient hypertension (N = 172) among nulliparous women who had had one or more abortions, with nulliparous women with no abortion as the referent group. Similar effects were seen for one spontaneous or induced abortion, when analyzed separately. A single prior abortion was associated with a decreased risk of preeclampsia [odds ratio (OR) = 0.35; 95% exact confidence interval (CI) = 0.09-1.01]. One abortion had only a small association with risk of transient hypertension (OR = 1.09, 95% exact CI = 0.68-1.72); however, a history of two or more abortions was associated with a decreased risk (OR = 0.42, 95% exact CI = 0.16-0.94). Among nulliparous women with a history of one abortion, a decreased risk of both hypertensive disorders was observed among women whose aborted pregnancy ended at > or =3 months gestation. These findings suggest that a history of abortion in nulliparous women is a protective factor against the risk of preeclampsia in the subsequent pregnancy.     

The relation between multiple births and maternal risk of breast cancer.

Data from two case-control studies conducted in New York State during 1982-1986 were used to examine the relation between multiple births and the maternal risk of breast cancer. The cases were 2,561 women between 20 and 79 years of age with a diagnosis of primary breast cancer. Controls (n = 2,616) were selected from driver's license files and matched to cases by year of birth and county of residence. The odds ratio for any multiple birth was 0.94 (95% confidence interval (CI) 0.56-1.56) in women less than 55 years of age and 0.95 (95% CI 0.62-1.46) in women aged 55-79 years. A previous study had shown a multiple last birth to be protective against breast cancer in women less than 55 years of age (odds ratio (OR) = 0.60, 95% CI 0.43-0.85). A decreased risk of breast cancer was also observed for this age group in the present study, but the magnitude of the effect was not as strong and the confidence interval included unity (OR = 0.85, 95% CI 0.43-1.68). A logistic model that controlled for age at first pregnancy, number of live births, age, and county of residence increased the odds ratio to 0.97 for a multiple last birth. The current study does not support an association between multiple births and maternal risk of breast cancer.     

兰州地区早产影响因素的研究

目的 探讨早产、自发性早产和医源性早产的相关高危因素.方法 回顾性调查2010年1月至2012年12月在甘肃省妇幼保健院住院分娩足月儿和早产儿的孕妇的住院资料,分娩足月活产儿5639例、早产儿540例,分为足月产组(≥37周孕龄)和早产组(<37周孕龄),比较早产组和足月产组发生早产的相关危险因素,以及自发性早产和医源性早产的相关高危因素.结果 ①Logistic回归分析发现教育年限(≥16年)(OR=0.61,95%CI:0.48~0.78)、家庭平均月收入(>3000元)(OR=0.62,95%CI:0.50~0.78)是早产发生的保护因素,而母亲妊娠合并症,比如妊娠期糖尿病(GDM)(OR=3.97,95%CI:1.70~9.25)、妊娠期高血压疾病(HDP)(OR=4.43,95%CI:3.35~5.87)、妊娠期胆汁淤积症(ICP)(OR=4.88,95%CI:3.25~7.32)是早产发生的独立高危因素.②按早产的病因分类,本研究中340例为自发性早产儿,余200例为医源性早产.经分层多因素非条件Logistic回归分析表明,与足月产相比,经产妇(OR=2.66,95%CI:1.87~3.76)、GDM(OR=4.52,95%CI:1.42~14.38),尤其是HDP孕妇(OR=14.19,95%CI:10.10~19.93)更易发生医源性早产,而ICP孕妇更多出现自发性流产(OR=12.875,95%CI:12.75~13.00).结论 应及早识别早产潜在的高危因素,加强围生期管理,以减少早产的发生,改善围生儿结局.     

Nutritional indicators of adverse pregnancy outcomes and mother-to-child transmission of HIV among HIV-infected women

BACKGROUND: Poor nutrition may be associated with mother-to-child transmission (MTCT) of HIV and other adverse pregnancy outcomes. OBJECTIVE: The objective was to examine the relation of nutritional indicators with adverse pregnancy outcomes among HIV-infected women in Tanzania, Zambia, and Malawi. DESIGN: Body mass index (BMI; in kg/m(2)) and hemoglobin concentrations at enrollment and weight change during pregnancy were prospectively related to fetal loss, neonatal death, low birth weight, preterm birth, and MTCT of HIV. RESULTS: In a multivariate analysis, having a BMI < 21.8 was significantly associated with preterm birth [odds ratio (OR): 1.82; 95% CI: 1.34, 2.46] and low birth weight (OR: 2.09; 95% CI: 1.41, 3.08). A U-shaped relation between weight change during pregnancy and preterm birth was observed. Severe anemia was significantly associated with fetal loss or stillbirth (OR: 3.67; 95% CI: 1.16, 11.66), preterm birth (OR: 2.08; 95% CI: 1.39, 3.10), low birth weight (OR: 1.76; 95% CI: 1.07, 2.90), and MTCT of HIV by the time of birth (OR: 2.26; 95% CI: 1.18, 4.34) and by 4-6 wk among those negative at birth (OR: 2.33; 95% CI: 1.15, 4.73). CONCLUSIONS: Anemia, poor weight gain during pregnancy, and low BMI in HIV-infected pregnant women are associated with increased risks of adverse infant outcomes and MTCT of HIV. Interventions that reduce the risk of wasting or anemia during pregnancy should be evaluated to determine their possible effect on the incidence of adverse pregnancy outcomes and MTCT of HIV.