Comparison of Risk Factors for Small-for-Gestational-Age and Preterm in a Portuguese Cohort of Newborns

Objective: To identify risk factors for small-for-gestational-age and preterm in a Portuguese cohort of newborns. Study design: Socio-demographic, anthropometric, behavioural and obstetrical characteristics were evaluated in 4.193 women consecutively delivered. Term small-for-gestational-age (n = 342) and non-small-for-gestational-age preterm (n = 148) were compared to non-small-for-gestational-age term births (n = 3538). Adjusted odds ratios and etiologic fractions were calculated. Results: Low height, low weight when entering pregnancy and low weight gain were significantly associated with small-for-gestational-age, but not preterm. These were the factors with the highest etiologic fraction for small-for-gestational-age. An increased risk of small-for-gestational-age was found for women who smoked during pregnancy (OR = 2.39; 95% CI: 1.66–3.46) and began antenatal care after pregnancy first trimester (OR = 1.86; 95% CI: 1.32–2.62). Previous abortion was associated with small-for-gestational-age (OR = 1.72; 95% CI: 1.16–2.55) and previous preterm with preterm (OR = 3.20; 95% CI: 1.26–8.14). Conclusions: Low anthropometrics, smoking and late antenatal care were risk factors for small-for-gestational-age, but not preterm. Maternal anthropometrics were the factors with the highest impact on small-for-gestational-age. No factor showed a great contribution to preterm birth.     

Mortality Among Twins Born to Unmarried Teenagers in the United States

Objective: The objective of this study is to determine the association between unmarried status and infant mortality among twins born to teenagers. Methods: We conducted a retrospective cohort study on twin live births to teenagers in the United States from 1995 through 1998 using the Vital Records assembled by the National Center for Health Statistics. We compared mortality estimates among twins of single to those of married mothers using the generalized estimating equation framework, which also adjusted for intracluster correlations. Results: Analysis involved 28592 individual twins of teenager mothers, with both cluster members being live-born. Out of these, 21.8% (n = 6238) were born to married and 78.2% (n = 22,354) to single mothers. Infant and postneonatal mortality was 17% and 36% higher among twins of single teenager mothers (odds ratio (OR) = 1.17; 95% confidence interval (CI) = 1.01–1.40) and (OR = 1.36; 95% CI = 1.01–1.87), respectively. However, neonatal mortality was comparable (OR = 1.12; 95% CI = 0.92–1.34). Twins of single mothers were also more likely to be of low birth weight, very low birth weight, preterm and very preterm (p < 0.0001) but had the same risk level for smallness for gestational age as compared to twins of married teenagers. Conclusions: Single motherhood was associated with increased infant mortality among twins born to teenagers. The critical time of elevated risk was the postneonatal period and the survival disadvantage of twins of single mothers was as a result of the higher-than-expected level of preterm rather than small for gestational age births. These findings have potential clinical and public health relevance.     

Impact of the Red River Catastrophic Flood on Women Giving Birth in North Dakota, 1994–2000

To document changes in birth rates, birth outcomes, and pregnancy risk factors among women giving birth after the 1997 Red River flood in North Dakota. We analyzed detailed county-level birth files pre-disaster (1994–1996) and post-disaster (1997–2000) in North Dakota. Crude birth rates and adjusted fertility rates were calculated. The demographic and pregnancy risk factors were described among women delivering singleton births. Logistic regression was conducted to examine associations between the disaster and low birth weight (<2,500 g), preterm birth (<37 weeks), and small for gestational age infants adjusting for confounders. The crude birth rate and direct-adjusted fertility rate decreased significantly after the disaster in North Dakota. The proportion of women giving birth who were older, non-white, unmarried, and had a higher education increased. Compared to pre-disaster, there were significant increases in the following maternal measures after the disaster: any medical risks (5.1–7.1%), anemia (0.7–1.1%), acute or chronic lung disease (0.4–0.5%), eclampsia (0.3–2.1%), and uterine bleeding (0.3–0.4%). In addition, there was a significant increase in births that were low birth weight (OR 1.11, 95% CI 1.03–1.21) and preterm (OR 1.09, 95% CI 1.03–1.16) after adjusting for maternal characteristics and smoking. Following the flood, there was an increase in medical risks, low birth weight, and preterm delivery among women giving birth in North Dakota. Further research that examines birth outcomes of women following a catastrophic disaster is warranted.     

Maternal Marital Status and Birth Outcomes: A Systematic Review and Meta-Analyses

Systematically review risks of an infant being born with low birth weight (LBW), preterm birth (PTB) or small for gestational age (SGA) among married and unmarried women. Medline, Embase, CINAHL, and bibliographies of identified articles were searched for English language studies. Studies reporting birth outcomes of married and unmarried (single and cohabitant) were included. Two reviewers independently collected data and assessed the quality of the studies for biases in sample selection, exposure assessment, confounder, analytical, outcome assessments, and attrition. Meta-analyses were performed using random effect model for both unadjusted and adjusted data and odds ratio (OR), and 95% confidence interval (CI) were calculated. Twenty-one studies of low to moderate risk of bias were included. Compared to married mothers unadjusted odds of (a) LBW was increased among unmarried (OR 1.46, 95%CI 1.25–1.71), single (OR 1.65, 95%CI 1.44–1.88) and cohabitating (OR 1.29, 95%CI 1.25–1.32) mothers; (b) PTB was increased among unmarried (OR 1.22, 95%CI 1.14–1.31), single (OR 1.54, 95%CI 1.39–1.72) and cohabitating (OR 1.15, 95%CI 1.08–1.23) mothers and (c) SGA birth was increased among unmarried (OR 1.45, 95%CI 1.32–1.61), single (OR 1.70, 95%CI 1.47–1.97) and cohabitating (OR 1.36, 95%CI 1.30–1.42) mothers. Meta-analyses of adjusted odds estimates confirmed these findings at marginally lower odds. Maternal unmarried status is associated with an increased risk of LBW, PTB and SGA births.     

The Association Between Major Birth Defects and Preterm Birth

Objective To evaluate the association between preterm birth and major birth defects by maternal and infant characteristics and specific types of birth defects. Study Design We pooled data for 1995–2000 from 13 states with population-based birth defects surveillance systems, representing about 30% of all U.S. births. Analyses were limited to singleton, live births from 24–44 weeks gestational age. Results Overall, birth defects were more than twice as common among preterm births (24–36 weeks) compared with term births (37–41 weeks gestation) (prevalence ratio [PR] = 2.65, 95% confidence interval [CI] 2.62–2.68), and approximately 8% of preterm births had a birth defect. Birth defects were over five times more likely among very preterm births (24–31 weeks gestation) compared with term births (PR = 5.25, 95% CI 5.15–5.35), with about 16% of very preterm births having a birth defect. Defects most strongly associated with very preterm birth included central nervous system defects (PR = 16.23, 95% CI 15.49–17.00) and cardiovascular defects (PR = 9.29, 95% CI 9.03–9.56). Conclusions Birth defects contribute to the occurrence of preterm birth. Research to identify shared causal pathways and risk factors could suggest appropriate interventions to reduce both preterm birth and birth defects.     

Maternal unemployment: an indicator of spontaneous preterm delivery risk

The aim of this study was to assess the association between maternal employment and preterm delivery. A nationwide case–control study was conducted in 25 Portuguese public maternities. During a 4-month period, 769 consecutive single spontaneous preterm (<37 gestation weeks) live births and 1,053 term singleton babies born immediately after each preterm, were evaluated. Information was obtained by attending physicians using a questionnaire, with special emphasis on maternal work characterization. Logistic regression odds ratios (OR) were adjusted for maternal age, marital status, education and obstetrical characteristics. Women entering pregnancy while unemployed presented a significantly increased risk of spontaneous preterm delivery (OR = 1.5; 95% confidence interval (CI) 1.18–1.88). Weekly duration of work (<40 versus ≥40 h) had no significant effect on the occurrence of spontaneous preterm (OR = 1.2; 95% CI 0.88–1.54). Unemployed women presented a significant increase in the risk of preterm delivery.     

History of fetal loss and other adverse pregnancy outcomes in relation to subsequent risk of preterm delivery

Objective: To evaluate the association between maternal reproductive history and preterm delivery. Methods: The 312 preterm delivery cases, studied in aggregate, and in subgroups (spontaneous preterm labor, preterm premature rupture of membranes, medically induced preterm delivery, moderate preterm delivery [gestational age at delivery 34–36 weeks], and very preterm delivery [gestational age at delivery <34 weeks]), were compared with 424 randomly selected women who delivered at term. Maternal medical records provided information on maternal reproductive history, pregnancy outcome, as well as sociodemographic characteristics. Using multivariate logistic regression, we derived maximum likelihood estimates of adjusted odds ratios (OR) and 95% confidence intervals (CI). Results: A history of 2+ miscarriages was ( OR = 2.2; 95% CI 1.2–3.9), but a history of 2+ prior induced abortions (OR = 1.2; 95% CI 0.7–2.0) was not, associated with preterm delivery in the index pregnancy. Analyses of preterm delivery subgroups indicated that a history of 2+ miscarriages was associated with an increasedrisk of spontaneous preterm labor (OR = 2.6; 95% CI 1.2–2.8), preterm premature rupture of membrane (OR = 1.8; 95% 0.7–4.4), and medically induced preterm delivery (OR = 1.9; 95% CI 0.8–4.2), though only the former approached statistical significance. Excess risk of preterm delivery was associated with maternal prior history of delivering a stillborn infant (OR = 10.7), a prior history of delivering a newborn that later died during the neonatal period (OR = 3.2), and a prior history of having a pregnancy complicated by spontaneous preterm delivery (OR = 6.0). Generally these associations were evident for each subgroup of preterm delivery, though inferences were often hindered by our relatively small sample size. Conclusions: These results support the hypothesis that maternal adverse reproductive history is associated with an increased risk of preterm labor and delivery.     

Low Birth Weight Across Generations: The Effect of Economic Environment

To determine whether economic environment across generations underlies the association of maternal low birth weight (<2,500 g, LBW) and infant LBW including its preterm (<37 weeks) and intrauterine growth retardation (IUGR) components. Stratified and multilevel logistic regression analyses were performed on an Illinois transgenerational dataset of White and African-American infants (1989–1991) and their mothers (1956–1976) with appended US census income data. Population Attributable Risk percentages were calculated to estimate the percentage of LBW births attributable to maternal LBW. Among Whites, former LBW mothers (N = 651) had an infant LBW rate of 7.1% versus 3.9% for former non-LBW mothers (N = 11,505); RR = 1.8 (1.4–2.5). In multilevel logistic regression models that controlled for economic environment and individual maternal risk factors, the adjusted OR of infant LBW, preterm birth, and intrauterine growth retardation for maternal LBW (compared to non-LBW) equaled 1.8 (1.3–2.5), 1.3 (1.0–1.8), and 1.8 (1.5–2.3), respectively. Among African-Americans, former LBW mothers (N = 3,087) had an infant LBW rate of 19.5% versus 13.3% for former non-LBW mothers (N = 18,558); RR = 1.5 (1.3–1.6). In multilevel logistic models of African-Americans, the adjusted OR of infant LBW, preterm birth, and IUGR for maternal LBW (compared to non-LBW) were 1.6 (1.4–1.8), 1.3 (1.2–1.5), and 1.6 (1.5–1.8), respectively. In both races, approximately five percent of LBW infants with mothers and maternal grandmother who resided in high-income neighborhoods were attributable to maternal LBW. A similar generational transmission of LBW including its component pathways of preterm birth and intrauterine growth retardation occurs in both races independent of economic environment across generations.     

Air pollution and stillbirth: a population-based case-control study in Taiwan

Background: There is limited evidence suggesting that prenatal exposure to ambient air pollutants may increase the risk of stillbirth, but previous epidemiological studies have not elaborated the most susceptible gestational period for the effects of air pollution exposure on stillbirth.Objectives: We estimated associations between exposure to ambient air pollutants and stillbirth, with special reference to the assessment of gestational periods when the fetus is most susceptible.Methods: We conducted a population-based case–control study in Taiwan. The case group consisted of 9,325 stillbirths, and the control group included 93,250 births randomly selected from 1,510,064 Taiwanese singleton newborns in 2001–2007. Adjusted logistic regression models were used to estimate odds ratios (ORs) per 10-ppb change for ozone and nitrogen dioxide, 1-ppb change for sulfur dioxide (SO₂), 10-μg/m³ change for particulate matter with aerodynamic diameter ≤ 10 μm (PM₁₀), and 100-ppb change for carbon monoxide during different gestational periods and according to term or preterm (< 37 weeks) birth status.Results: Stillbirth increased in association with a 1-ppb increase in first-trimester SO₂ [adjusted OR = 1.02; 95% confidence interval (CI), 1.00–1.04], particularly among preterm births (adjusted OR = 1.04; 95% CI, 1.01–1.07). Stillbirth was also associated with a 10-μg/m³ increase in PM₁₀ during the first (adjusted OR = 1.02; 95% CI, 1.00–1.05) and second (adjusted OR = 1.02; 95% CI, 1.00–1.04) month of gestation, and, as with SO₂, associations appeared to be restricted to preterm births (first-trimester adjusted OR = 1.03; 95% CI, 1.00–1.07).Conclusion: The study provides evidence that exposure to outdoor air SO₂ and PM₁₀ may increase the risk of stillbirth, especially among preterm births, and that the most susceptible time periods for exposure are during the first trimester of gestation.     

Moderate alcohol drinking and risk of preterm birth

OBJECTIVE: We have analysed the association between alcohol drinking before and during the three trimesters of pregnancy and risk of preterm birth of babies with normal weight for gestational age or with low weight for gestational age (SGA). DESIGN: Case-control study. SETTING: General and university hospitals in Italy. SUBJECTS: Cases were 502 women who delivered preterm births <37 weeks gestation. The controls included 1966 women who gave birth at term (>/=37 weeks of gestation) to healthy infants of normal weight (ie between 10th and 90th centile according to the Italian standard) on randomly selected days at the hospitals where cases had been identified. INTERVENTIONS: Interview. RESULTS: No increased risk of preterm birth was observed in women drinking one or two drinks/die in pregnancy, but three or more drinks/die increased the risk (multivariate odds ratios (OR) 2.0 for >/=3 drinks during the first trimester, 1.8 during the second and 1.9 during the third). When the analysis was conducted separately for preterm births with normal weight or SGA, the increased risk was observed in preterm SGA only (multivariate OR for >/=3 drinks/die during the first trimester=3.6, 95% confidence interval (CI) 1.3-11.1); the estimated multivariate OR for >/=3 drinks/die during the first trimester of preterm babies with normal weight for gestational age was only slightly above unity and not statistically significant (multivariate OR 1.4, 95% CI 0.5-3.7). CONCLUSIONS: The study shows an increased risk in mothers who drink >/=3 die units alcohol in pregnancy of preterm births.     

Length of Prenatal Participation in WIC and Risk of Delivering a Small for Gestational Age Infant: Florida, 1996–2004

Objective To assess the association between length of prenatal participation in WIC and a marker of infant morbidity. By focusing on small for gestational age, we consider one of the possible pathways through which prenatal nutrition affects fetal growth. Design/Methods The study sample consists of 369,535 matched mother-infant pairs drawn from all singleton live births in Florida hospitals from 1996 to 2004. All subjects received WIC and Medicaid-funded prenatal services during pregnancy. We controlled for selection bias on observed variables using a generalized propensity scoring approach and performed separate analyses by gestational age category to control for simultaneity bias. Results Ten percent increase in the percent of time in WIC was associated with 2.5% decrease (95% CI: 2.1–3.0%) in the risk of a full-term an SGA infant. The risk was also significantly decreased for very preterm and late preterm infants (29–33 and 34–36 weeks gestation) but not for extremely preterm infants (23–28 weeks gestation). Conclusions The observed small negative dose response relationship between percent of pregnancy spent in WIC and fetal growth restriction implies that longer participation in the program confers a small measure of protection against delivering an SGA infant.     

Work as a physician and adverse pregnancy outcomes: a Finnish nationwide population-based registry study

Work as a physician may be related to several occupational hazards. Only few studies have investigated the relations between work as a physician and the risk of adverse pregnancy outcomes and the results have been inconsistent. We conducted a nationwide population-based study in Finland to assess whether work as a physician during pregnancy increases the risk of adverse pregnancy outcomes. We identified from the 1990 to 2006 Finnish Medical Birth Register data all singleton newborns of physicians (N = 7,642) and other upper white collar workers (N = 124,606; as the reference group) from a source population of 946,392 singleton newborns. In generalized estimating equations, work as a physician was not related to low birth weight (adjusted odds ratio (OR) 1.00, 95% confidence interval (CI 0.86–1.15), preterm delivery (1.00, 0.89–1.12), small-for-gestational age (1.04, 0.86–1.22), large-for-gestational age (1.00, 0.86–1.13), perinatal death (0.88, 0.49–1.27), and the female gender of the newborn (0.98, 0.94–1.03). The risk of high birth weight (4,000 g or more; 0.88, 0.84–0.93) and postterm delivery were lower (0.77, 0.65–0.89) among physicians than the reference group. The results indicate that Finnish female physicians have a similar risk of adverse pregnancy outcomes as women of similar socio-economic background.     

Paternal and maternal exposure to welding fumes and metal dusts or fumes and adverse pregnancy outcomes

Objective  We assessed whether paternal exposure prior to conception and maternal exposure during pregnancy to welding fumes (WF) and metal dusts or fumes (MD/F) independently and jointly increases the risk of preterm delivery, low birth weight, and small-for-gestational age. Methods  The study population was selected from The Finnish Prenatal Environment and Health Study of 2,568 newborns (response rate 94%) and included 1,670 women who worked during pregnancy of which 68 were exposed either to WF and/or MD/F. Results  The risk of SGA was related to maternal exposure to WF only (adjusted OR = 1.78; 95% CI 0.53–5.99), MD/F only (adjusted OR = 1.77; 95% CI 0.38–8.35) and both exposures (2.92; 1.26–6.78). The corresponding effect estimates for preterm delivery were 2.66 (0.32–22.08), 5.64 (1.14–27.81) and for birth weight below 3,000 g 3.79 (1.09–13.19), 1.85 (0.56–6.14) and 1.70 (0.70–4.15), respectively. There was some suggestive, inconsistent evidence that the risk of preterm delivery and SGA is related to paternal exposure to WF. Conclusions  The present results provide evidence that maternal exposure to WF or MD/F combination during pregnancy may reduce fetal growth and suggestive evidence that paternal exposure to WF may increase the risk of preterm delivery and small-for-gestational age. The small number of exposed women and the lack of data for exposure concentrations suggest the need for further study to verify our findings.     

Intra-familial Transmission of Helicobacter pylori Infection in Children of Households with Multiple Generations in Vietnam

This community-based cross-sectional study in 533 participants from 135 households with multiple generations living in the same household aimed at investigating the relationship between Helicobacter pylori infection in children and the other household members. H. pylori infection in children was found significantly associated with the infection in mothers [OR (95% CI): 2.50 (1.19–5.26)], even after being adjusted for sex, age group and sibling number [adjusted OR (95% CI): 2.47 (1.12–5.47)]. It was also significantly associated with the infection in␣both parents [adjusted OR (95% CI): 4.14 (1.29–13.23)]. No significant association between H. pylori infection in the father, grandparent(s), uncle or aunt with that in their children was found. Results from the present study showed intra-familial transmission in a multi-generation population and supported the␣hypothesis of person-to-person transmission of H.␣pylori infection.     

Pre-Pregnancy Body Mass Index and Weight Gain During Pregnancy: Relations with Gestational Diabetes and Hypertension, and Birth Outcomes

To study the relationship between pre-pregnancy body mass index (BMI) and weight gain during pregnancy with pregnancy and birth outcomes, with a focus on gestational diabetes and hypertension and their role in the association with fetal growth. We studied 1,884 mothers and offspring from the Eden mother–child cohort. Weight before pregnancy (W1) and weight after delivery (W2) were collected and we calculated BMI and net gestational weight gain (netGWG = (W2 − W1)/(weeks of gestation)). Gestational diabetes, hypertension gestational age and birth weight were collected. We used multivariate linear or logistic models to study the association between BMI, netGWG and pregnancy and birth outcomes, adjusting for center, maternal age and height, parity and average number of cigarettes smoked per day during pregnancy. High BMI was more strongly related to the risk of giving birth to a large-for-gestational-age (LGA) baby than high netGWG (odds ratio OR [95% CI] of 3.23 [1.86–5.60] and 1.61 [0.91–2.85], respectively). However, after excluding mothers with gestational diabetes or hypertension the ORs for LGA, respectively weakened (OR 2.57 [1.29–5.13]) for obese women and strengthened for high netGWG (OR 2.08 [1.14–3.80]). Low in comparison to normal netGWG had an OR of 2.18 [1.20–3.99] for pre-term birth, which became stronger after accounting for blood pressure and glucose disorders (OR 2.70 [1.37–5.34]). Higher net gestational weight gain was significantly associated with an increased risk of LGA only after accounting for blood pressure and glucose disorders. High gestational weight gain should not be neglected in regard to risk of LGA in women without apparent risk factors.     

Preterm delivery and exposure to active and passive smoking during pregnancy: a case-control study from Italy

The aim of this study was to assess the relationship between preterm/early preterm delivery and active smoking as well as environmental tobacco smoke (ETS) exposure in a sample of pregnant Italian women. A case-control study was conducted in nine cities in Italy between October 1999 and September 2000. Cases of preterm birth were singleton babies born before the 37th gestational week; babies born before the 35th gestational week were considered early preterm births. Controls were babies with gestational ages >or= 37th week. A total of 299 preterm cases (including 105 early preterm) and 855 controls were analysed. A self-administered questionnaire was used to assess active smoking and ETS exposure, as well as potential confounders. Multivariable logistic regression analysis showed a relationship between active smoking during pregnancy and preterm/early preterm delivery [adjusted ORs: 1.53; 95% CI 1.05, 2.21 and 2.00; 95% CI 1.16, 3.45, respectively]. A dose-response relationship was found for the number of cigarettes smoked daily. The adjusted ORs were 1.54 and 1.69 for preterm babies and 1.90 and 2.46 for early preterm babies for 1-10 and >10 cigarettes/day respectively. ETS exposure was associated with early preterm delivery [adjusted OR 1.56; 95% CI 0.99, 2.46] with a dose-response relationship with the number of smokers in the home. Smoking during pregnancy was strongly associated with preterm delivery with a dose-response effect. ETS exposure in non-smoking women was associated only with early preterm delivery.     

Does lack of multinutrient supplementation during early pregnancy increase vulnerability to alcohol-related preterm or small-for-gestational-age births?

The objective of this study was to assess whether women who do not take multinutrient supplements during early pregnancy are more susceptible to the effects of low-to-moderate alcohol consumption on preterm birth and small-for-gestational-age birth (SGA) compared to women who do take multinutrients. This analysis included 800 singleton live births to mothers from a cohort of pregnant women recruited for a population-based cohort study conducted in the Kaiser Permanente Medical Care Program in Northern California. Participants were recruited in their first trimester of pregnancy and information about their alcohol use and supplement intake during pregnancy was collected. Preterm birth (n = 53, 7%) was defined as a delivery prior to 37 completed weeks of gestation and SGA birth (n = 124, 16%) was defined as birth weight less than the 10th percentile for the infant’s gestational age and sex compared to US singleton live births. A twofold increase in the odds of SGA birth attributed to low-to-moderate alcohol intake was found among multinutrient supplement non-users (95% CI: 1.1, 5.3). Yet, among multinutrient supplement users, there was no increased risk of an SGA birth for women who drank low-to-moderately compared to women who abstained (aOR: 0.97, 95% CI: 0.6, 1.6). Similar results emerged for preterm birth. Our findings provide marginal evidence that multinutrient supplementation during early pregnancy may modify the risk of SGA births and preterm birth associated with alcohol consumption during pregnancy and may have important implications for pregnant women and women of child-bearing age. However, future research needs to be conducted.     

Comparison of allergic diseases,symptoms and respiratory infections between Finnish and Russian school children

Background Little is known about differences in allergic and respiratory diseases between the Finnish and Russian populations. Methods We conducted a population-based cross-sectional study to compare the occurrence of allergic diseases and respiratory infections among school children in the towns of Imatra in Finland and Svetogorsk in Russia on either side of the common border. The study population consisted of 512 Finnish and 581 Russian school children aged 7–16 years (response rate 79%). We used multiple logistic regression analysis to calculate odds ratios adjusting for age and gender. Results The prevalences of asthma (6.7 vs. 3.9%, adjusted odds ratio (OR) 1.54, 95% confidence interval (CI 0.87–2.71), allergic rhinitis (15.2 vs. 8.8%, OR 1.81, 1.22–2.68), allergic conjunctivitis (4.7 vs. 3.2%, 1.33, 0.70–2.53), and atopic dermatitis (10.5 vs. 5.9%, 1.78, 1.12–2.83) were substantially higher among school children in Imatra compared to those in Svetogorsk, but the symptoms were more severe among allergic Russian children. Tonsillitis (adjusted OR 0.11, 95% CI 0.07–0.17), sinusitis (0.39, 0.24–0.63), bronchitis (0.41, 0.27–0.62) and pneumonia (0.19, 0.04–0.90) occurred less frequently in the Finnish children, whereas otitis media (2.37, 1.55–3.62) and common cold (4.07, 3.12–5.31) were more frequent in Finland. Conclusions Allergic diseases are more common in Finnish than Russian school children, but the symptoms are more severe among allergic Russian children. Respiratory infections are in general more frequent in Russian children. “Western” lifestyle habits, differences in diagnostic procedures and environmental factors, and availability of health care and medications are discussed as possible explanations for the observed differences.     

The use of data set of the Hungarian case-control surveillance of congenital abnormalities for evaluation of birth outcomes beyond birth defects

AIMS: To use the data set of the Hungarian Case-Control Surveillance of Congenital Abnormalities (HCCSCA) for the evaluation of birth outcomes beyond congenital abnormalities and to show as example the study of 49 antimicrobial drugs used in Hungary for the reduction of preterm births. METHODS: The population-based data set of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996, included 38,151 newborn infants without birth defects and this sample represented 1.8% of Hungarian births. Medically recorded gestational age at delivery and birthweight, in addition the rate of preterm births and low birthweight newborns born to mothers with or without different antimicrobial drugs used at least by ten pregnant women were analysed. RESULTS: Of 49 antimicrobial drugs, two: ampicillin (adjusted POR with 95% CI: 0.8, 0.7-0.9) and clotrimazole (0.8, 0.7-0.9) showed a preterm birth preventive effect. This preterm preventive effect was found mainly after the use of ampicillin and clotrimazole during the first trimester of pregnancy. CONCLUSIONS: Ampicillin and clotrimazole may be effective for the reduction of preterm births due to infectious diseases of pregnant women in general but particularly caused by genital infections. However, the limitation of the data set did not allow the appropriate evaluation of some antimicrobial drugs (e.g. clindamycin).     

Birth Outcomes Among Older Mothers in Rural Versus Urban Areas: A Residence‐Based Approach

Purpose: We examined the association between rural residence and birth outcomes in older mothers, the effect of parity on this association, and the trend in adverse birth outcomes in relation to the distance to the nearest hospital with cesarean‐section capacity. Methods: A population‐based retrospective cohort study, including all singleton births to 35+ year‐old women in British Columbia (Canada), 1999‐2003. We compared birth outcomes in rural versus urban areas, and between 3 distance categories to a hospital (<50, 50‐150, >150 km). Outcomes included labor induction, cesarean section, stillbirth, perinatal death, preterm birth (<37 weeks), small‐for‐gestational‐age, large‐for‐gestational‐age, and neonatal intensive care unit admission. We used multivariate regression to obtain adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Findings: Among the 29,698 subjects, 11.5% lived in rural areas; 5% lived within 50‐150 km; and 1.1% lived >150 km from a hospital. Rural women were at lower risk of primary and repeat cesarean section (OR = 0.9, CI: 0.9‐1.0; OR = 0.7, CI: 0.6‐0.9) and small‐for‐gestational‐age (OR = 0.8, CI: 0.7‐0.9) births; they were at increased risk for perinatal death (OR = 1.5, CI: 1.1‐2.1) and large‐for‐gestational‐age (OR = 1.1, CI: 1.1‐1.2) births. The association was stronger among multiparous versus primiparous women. No differences in emergency cesarean section, preterm birth, or neonatal intensive care admission were found, regardless of parity. Perinatal mortality increased with distance from hospital; OR = 1.5 (CI: 1.1‐2.1) per distance category. Conclusions: Older women in rural versus urban areas had a lower rate of cesarean section and increased risk of perinatal death. The risk of perinatal death increased with the distance to hospital. Further studies need to evaluate the contribution of underlying perinatal risks, access to care, and decision making regarding referral and transport.