Maternal flu, fever, and the risk of neural tube defects: a population-based case-control study

Results of clinical and epidemiologic studies have shown an increased risk for neural tube defects (NTD) in infants whose mothers were exposed to heat during pregnancy. However, the risk for NTD in infants whose mothers had influenza during pregnancy has not been well studied. This population-based case-control study of infants born in metropolitan Atlanta, Georgia, from 1968 through 1980 included 385 infants with NTD, 3,647 infants with other birth defects, and 2,676 infants without birth defects. Of the 385 mothers of case infants, 31 reported having a 2-day or longer episode of flu with fever from 1 month before through 3 months after conception (odds ratio (OR) = 3.0; 95% confidence interval (CI) 1.9-4.7). Infants of mothers who took medications for their episodes of flu with fever had an even higher risk for NTD (OR = 4.3, 95% CI 2.6-7.1). When mothers of infants with birth defects other than NTD were used as controls, an increased risk of NTD remained for flu with fever (OR = 1.7, 95% CI 1.1-2.5). There was no increased risk for NTD among the infants of mothers who reported fever from causes other than flu. Because of the heterogeneity of maternal flu, the individual contributions of infection, fever, and medications remain difficult to disentangle.     

Birth weight reduction associated with residence near a hazardous waste landfill

We examined the relationship between birth weight and mother's residence near a hazardous waste landfill. Twenty-five years of birth certificates (1961-1985) were collected for four towns. Births were grouped into five 5-year periods corresponding to hypothesized exposure periods (1971-1975 having the greatest potential for exposure). From 1971 to 1975, term births (37-44 weeks gestation) to parents living closest to the landfill (Area 1A) had a statistically significant lower average birth weight (192 g) and a statistically significant higher proportion of low birth weight [odds ratio (OR) = 5.1; 95% confidence interval (CI), 2.1-12.3] than the control population. Average term birth weights in Area 1A rebounded by about 332 g after 1975. Parallel results were found for all births (gestational age > 27 weeks) in Area 1A during 1971-1975. Area 1A infants had twice the risk of prematurity (OR = 2.1; 95 CI, 1.0-4.4) during 1971-1975 compared to the control group. The results indicate a significant impact to infants born to residents living near the landfill during the period postulated as having the greatest potential for exposure. The magnitude of the effect is in the range of birth weight reduction due to cigarette smoking during pregnancy.     

Relation of parental birth weights to infant birth weight among African Americans and whites in Illinois: a transgenerational study

The authors used a transgenerational data set of Illinois vital records to ascertain the relation between parental birth weights and infant birth weight. The infant generation consisted of all African Americans and whites born in Illinois during 1989-1991. The parent generation included the mothers and fathers who were also born in Illinois between 1956 and 1975. In the infant cohort, the rate of low birth weight (LBW) (<2,500 g) was 11.7% for African Americans (n = 15,287) versus 5.0% for whites (n = 117,708) (relative risk (RR) = 2.3, 95% confidence interval (CI) 2.2-2.5). For African Americans, the LBW rate was 17.9% among those born to LBW mothers (n = 1,943) compared with 10.8% among those born to non-LBW mothers (n = 13,344) (RR = 1.8, 95% CI 1.6-1.9). For whites, the LBW rate was 8.5% among those born to LBW mothers (n = 2,174) compared with 4.8% among those born to non-LBW mothers (n = 115,534) (RR = 1.7, 95% CI 1.6-2.0). A weaker association was observed between paternal birth weight and infant birth weight. The authors conclude that parental birth weights are important risk factors for LBW in both African Americans and whites.     

The spontaneous gating activity of OmpC porin is affected by mutations of a putative hydrogen bond network or of a salt bridge between the L3 loop and the barrel

Nineteen counties from San Francisco and Los Angeles, California and Seattle, Washington were the United States sites for a large population-based case-control study of childhood brain tumors (CBTs), sponsored by the National Cancer Institute. CBT patients who were < 20 years of age and were diagnosed between 1984 and 1991 were reported to each region's cancer registry. The 801 control subjects were obtained by random digit dial and were frequency-matched to the 540 CBT patients in San Francisco and Seattle (one patient to two controls) and in Los Angeles (one patient to one control). Data collected by in-person interview with subjects' mothers were analyzed to investigate an association between risk for CBTs and life on a farm, exposure to farm animals (dairy cattle, beef cattle, pigs, sheep/goats, poultry, and horses), and some cat and non-farm horse exposures. Elevated risks for CBTs were observed in association with mothers' exposure to pigs [odds ratio (OR) = 3.8, 95% confidence interval (CI) = 1.2-12] and horses (OR = 2.2, 95% CI = 1.0-4.8) on a farm during the index pregnancy. Children diagnosed with primitive neuroectodermal tumors showed elevated risks for CBTs with personal and maternal prenatal exposure to pigs (child, OR = 4.0, 95% CI = 1.2-13; mother, OR = 11.9, 95% CI = 2.8-51) and poultry (child, OR = 3.0, 95% CI = 1.1-8.0; mother, OR = 4.0, 95% CI = 1.2-14). No other animal exposures of children or mothers were found to be consistently related to CBTs. Children diagnosed with primitive neuroectodermal tumors who were on a farm for > 1 year and were first on a farm when they were < 6 months of age also had increased risk for CBTs (OR = 3.9, 95% CI = 1.2-13). A somewhat increased risk for CBTs was found for children of mothers who ever had worked on livestock farms compared with mothers who never had worked on a farm (OR = 7.4, 95% CI = 0.86-64, based on five case mothers and one control mother who worked on livestock farms during the 5 years preceding the birth of the index child). The associations are consistent with those of two previous studies in Norway (P. Kristensen et al., Int. J. Cancer, 65: 39-50, 1996) and the United States and Canada (G. R. Bunin et al., Cancer Epidemiol. Biomark. Prev., 3: 197-204, 1994) that investigated the role of farm-related exposures in the etiology of CBTs.     

Meningiomas in the region of the cavernous sinus: a review of 21 patients

OBJECTIVE: To compare the morbidities in the very low birthweight (VLBW; < 1500 g) and normal birthweight (NBW; > or = 2500 g) Malaysian infants during the first year of life. METHODOLOGY: Prospective observational cohort study of consecutive surviving VLBW infants and randomly sampled NBW infants born in the Kuala Lumpur Maternity Hospital between 1 December 1989 and 31 December 1992. Infants were followed up regularly during the first year of life, after correction for prematurity. RESULTS: Compared with NBW infants (n = 106), VLBW infants (n = 127) had significantly higher risk of failure to thrive (odds ratio [OR] = 8.0, 95% confidence intervals [CI]: 1.1 to 354.3), wheezing (OR = 3.7, 95% CI: 1.6 to 9.3), rehospitalization (OR = 2.3, 95% CI: 1.1 to 5.0), cerebral palsy (OR = 8.6, 95% CI: 2.0 to 77.6), neurosensory hearing loss (OR = 12.0, 95% CI: 1.7 to 513.6) and visual loss (7.9 vs 0%, P = 0.002). The mean mental developmental index (MDI) and mean psychomotor developmental index (PDI) at 1 year of age were significantly lower among VLBW infants (MDI 99 [SD = 28], PDI 89 [SD = 25]) than NBW infants (MDI 106 [SD = 18], PDI 101 [SD = 18]) (95% CI for difference between means being MDI: -14.1 to -1.7; and PDI: -17.6 to -6.0). Logistic regression analysis showed that among VLBW infants: (i) male sex, Malay ethnicity and bronchopulmonary dysplasia were significant risk factors associated with wheezing; (ii) longer duration of oxygen therapy during the neonatal period, seizures after the post-neonatal period and wheezing were significant risk factors associated with rehospitalization; and (iii) longer duration of oxygen therapy during the neonatal period was a significant risk factor associated with adverse neurodevelopmental outcome during the first year of life. CONCLUSIONS: Compared with NBW infants, VLBW Malaysian infants had significantly higher risks of physical and neuro-developmental morbidities.     

Depression and suicidal ideation in dermatology patients with acne, alopecia areata, atopic dermatitis and psoriasis

OBJECTIVE: To determine the birth prevalence of and risk factors associated with congenital esotropia. DESIGN: Population-based prevalence study with nested case-control study. PARTICIPANTS: All residents of Olmsted County, Minnesota who were diagnosed with congenital esotropia and born between January 1, 1980 and December 31, 1989 (n = 47). Control subjects were chosen by selecting the next two sequential births to parents residing in Olmsted County, Minnesota (n = 94). METHODS: Cases were identified through the Medical Diagnostic Index of Mayo and the Rochester Epidemiology Project. The community medical records were reviewed to confirm case status and ascertain risk factor information. MAIN OUTCOME MEASURE: Birth prevalence of congenital esotropia. RESULTS: Forty-seven cases were identified from 17,536 live births, for a birth prevalence of 27 per 10,000 (95% confidence interval [CI], 20-35). Congenital esotropia was associated with prematurity (odds ratio [OR], 11.5; 95% CI, 3.4-39.2), a birth weight less than 2500 grams (OR, 4.6; 95% CI, 1.7-12.9), a low Apgar score at 1 minute (OR, 4.3; 95% CI, 1.7-11.2) and at 5 minutes (OR, 6.3; 95% CI, 1.3-30.7), and a family history of strabismus (OR, 3.5; 95% CI, 1.5-8.3). CONCLUSIONS: The birth prevalence of congenital esotropia in Olmsted County, Minnesota is lower than previous estimates. Prematurity, low birth weight, low Apgar scores, and a family history of strabismus are significant risk factors for congenital esotropia.     

Infants conceived using in-vitro fertilization do not over-utilize health care resources after the neonatal period

Health outcomes during the first year for 95 infants born following in-vitro fertilization (IVF) were compared with those of 79 naturally conceived controls whose mothers were of identical parity and similar age. Primigravid women were enrolled prospectively at 30 weeks gestation, perinatal and neonatal data were collected during pregnancy and following birth, and details of health care resource use were obtained from mothers at 4 and 12 months. Median (range) number of medical problems during the first year tended to be less for IVF infants, 4 (0-41) versus 5 (0-12) (P = 0.07), whilst total number of visits to health care workers was similar for IVF and control infants, 19 (2-47) versus 19 (1-47). IVF infants were more likely to have an excessive number of visits to Early Childhood Health Care Centres [odds ratio (OR; 95% confidence interval, CI) = 2.44 (1.11-5.56)], but less likely to have an excessive number of visits to general medical practitioners [OR = 0.45 (0.22-0.93)] and other health care workers [OR = 0.48 (0.23-0.99)]. These data provide some degree of reassurance about medium-term health outcomes for children conceived using IVF. Although they are more likely to utilize the resources of neonatal intensive care units, IVF infants do not appear to have an increased number of medical problems or to over-utilize health care resources during the remainder of their first year of life.     

Paracrine stimulation of cell growth by cholecystokinin/gastrin through cholecystokinin-B receptor on GH3 cells in vitro

Self-reported reproductive histories of male employees of a lead-zinc smelter were related to pre-conception measures of lead exposure to examine associations between paternal occupational lead exposure and adverse pregnancy outcome. The participants reported 2,021 pregnancies which resulted in 1,684 normal live births, 12 stillbirths, 30 birth defects, 203 spontaneous abortions, and 92 "other" outcomes. Birth defects and stillbirths were combined for the analysis. The risk of a stillbirth or birth defect was elevated for pre-conception employment in a high-lead-exposure compared with a low-lead-exposure job (odds ratio = 2.7, 95% confidence interval = 0.7, 9.6). A similar risk was found for pre-conception blood lead levels of 25-39 μg/dL and >/= 40 μg/dL when compared with blood lead levels of < 25 μg/dL (OR = 2.9, 95% CI = 0.6, 13.3, and OR = 2.5, 95% CI = 0.5, 11.6, respectively). No association was found between pre-conception lead exposure and spontaneous abortion. A relatively low response rate to the questionnaire and potentially erroneous reporting of reproductive outcomes by male workers are limitations of the study.     

Cellular glutathione peroxidase is the mediator of body selenium to protect against paraquat lethality in transgenic mice

A case-control study was conducted between 1992 and 1996 in six Italian areas. It included 537 women with colon cancer, 291 women with rectal cancer and 2081 control women in hospital for acute conditions, unrelated to hormonal or gynaecological diseases. A higher age at menopause was associated with increased colon cancer risk (odds ratio (OR) for > or = 53 years compared with < 50 years = 1.39, 95% confidence interval (CI) 1.04-1.87). Among parous women, a significant trend of decreasing colon cancer risk with increasing number of births was seen for colon (OR for > or = 4 births compared with 1 birth = 0.62, 95% CI 0.42-0.90), but not for rectal cancer. Nulliparous women, however, were at lower risk than women with a single birth, and age at first birth was directly associated with risk. While oral contraceptive use showed no significant influence, ever users of hormone replacement therapy had a reduced risk of rectal cancer (OR = 0.56, 95% CI 0.31-1.01). Thus, the association of colorectal cancer with reproductive and menstrual factors is neither strong nor consistent.     

Thrombolytic treatment of acute myocardial infarct. 3]

In a population of close to 2.5 million infants born from 1983 to 1993 registered in the California Birth Defects Monitoring Program, we compared the prevalence of structural birth defects among 2,894 infants with Down syndrome (DS) with that of infants without DS. Among 61 defects uniformly ascertained in affected and unaffected infants, 45 were significantly more common in DS, with atrioventricular canal (risk ratio = 1,009), duodenal atresia (risk ratio = 265), and annular pancreas (risk ratio = 430) being the most common. Most defects of blastogenesis and most midline defects were either nonsignificantly associated or not observed in infants with DS. Theories on the pathogenesis of defects in trisomies must account for the lack of and for the presence of specific defects.     

Maternal smoking, body mass index, and neural tube defects

The Swedish health registries were used to investigate a possible effect on the incidence of neural tube defects (NTDs) of maternal smoking and maternal body mass index (BMI) (kg/m2). Among 1,199,701 infants born in 1983-1993 with known smoking exposure in early pregnancy, 621 infants with NTDs were selected. After controlling for year of birth, maternal age, parity, education level, BMI, and immigrant status (yes/no), a highly significant, protective effect of maternal smoking on the incidence of NTDs was found. The adjusted odds ratios (OR) and (95% confidence intervals (CI)) for maternal smoking among infants with NTDs (total), anencephaly, and spina bifida were 0.75 (0.61-0.91), 0.49 (0.28-0.85), and 0.76 (0.61-0.95), respectively. A protective dose-response effect of smoking was indicated but was not statistically significant. The association between NTDs and maternal BMI found in earlier studies was supported. Women with BMI >26.0 were found to be at higher risk of having an infant with NTD compared with women in other BMI classes (adjusted OR=1.35, 95% CI 1.00-1.83). For women with BMI > or =29, the corresponding odds ratio was 1.29 (0.81-2.05). No obvious explanation was found, either for the detected association between NTDs and BMI, or for the protective effect of maternal smoking.     

Preterm birth and cerebral palsy. Predictive value of pregnancy complications, mode of delivery, and Apgar scores

BACKGROUND: Preterm infants are at 8 times higher risk than term infants for pre- and perinatal brain damage, resulting in cerebral palsy. In this paper we have analysed the influence of prenatal and birth-related risk factors on cerebral palsy in preterm infants. METHODS: In a register-based study, 175 preterm singleton infants with cerebral palsy, born in 1982-86, were compared with 687 controls matched by gestational age and year of birth. RESULTS: Statistically significant higher rates in cases were found in parity > or = 3 (22% vs. 16%, p < 0.05), Cesarean section (67% vs. 56%, p < 0.01), and low Apgar scores at 1 minute (45% vs. 36%, p < 0.05). By multivariate analyses, two variables remained statistically significant: parity > or = 3 (adjusted OR = 1.53 (95% CI 1.00-2.34), p < 0.05) and Cesarean section (adjusted OR = 1.57 (95% CI 1.07-2.32), p < 0.05). CONCLUSIONS: Pregnancy complications preceding preterm birth did not imply a higher risk of cerebral palsy. Delivery by Cesarean section was a prognostic factor for developing cerebral palsy, and the predictive value of Apgar scores was highly limited.     

Potential risk factors for vertical HIV-1 transmission in Catalonia, Spain: the protective role of cesarean section. The Working Group on HIV-1 Vertical Transmission in Catalonia

OBJECTIVE: To evaluate the roles of certain potential risk factors on the vertical transmission of HIV-1. DESIGN: Prospective registry of infants born to HIV-1-infected women in Catalonia (north-east Spain) from 1987 to 1992. METHODS: A total of 599 infants, born in Catalan hospitals to 520 women who were identified as being HIV-1-infected during gestation or at delivery, were included. Data on mode of delivery, birth weight, gestational age and breast-feeding as well as the mother's age, her route of HIV-1 infection, clinical stage and p24 antigenaemia, were recorded. HIV-1 infection status of 489 (82%) of the infants was determined according to the criteria of the US Centers for Disease Control and Prevention. Risk estimates and odds ratio (OR) were calculated and logistic regression was performed. RESULTS: The overall rate of vertical transmission was 18.6% (95% confidence interval, 15.2-22.0%). Multivariate analyses revealed that Cesarean section was associated with a lower rate of vertical transmission (OR = 0.3; P = 0.001), as was maternal HIV-1 infection via injecting drug use (OR = 0.44; P = 0.02). Breast-feeding (OR = 6.9; P = 0.001), very low birth weight (< 1500 g; OR = 6.3; P = 0.001) and p24 antigenaemia (OR = 4.6; P = 0.04) were all related to increased risk. The crude rate of HIV-1 transmission was 6% among Cesarean births compared with 21% for infants born via vaginal deliveries. The population-attributable risk for vaginal deliveries was 61.7%. CONCLUSIONS: The results show a protective effect of Cesarean section in the absence of zidovudine prophylaxis. However, current research should be directed towards the individual and combined effects that antiretroviral agents and Cesarean section may have on mother-to-child HIV-1 infection.     

Heart rate variability in 1-day-old infants born at 4330 m altitude

BACKGROUND: Rates of low-birth-weight (LBW) infants are similar between Latina and white women, an epidemiologic paradox. However, few studies have analyzed the relationship between ethnicity, Latino subgroup, confounding variables, and LBW. METHODS: We analyzed 395070 singleton livebirths to Latina and non-Latina white women in California during 1992. Multivariate logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the risks due to Latino ethnicity and Latino subgroup for very LBW (VLBW, 500-1499 g) and moderately LBW (MLBW, 1500-2499 g) outcomes. RESULTS: Latina and white women had similar unadjusted rates of VLBW (0.7% vs. 0.6%) and MLBW infants (3.7% vs. 3.4%). After adjusting for maternal age, education, birthplace, marital status, parity, tobacco use, use of prenatal care, infant sex, and gestational age, there was no difference in the odds of VLBW infants between Latina and white women (OR, 0.93 [95% CI, 0.81-1.071). Latina women had minimally elevated odds of MLBW infants (OR, 1.06 [95% CI, 1.01-1.11]) compared with white women. By Latino subgroup, there was no difference in the adjusted odds of VLBW infants among Central and South American, Cuban, Mexican, Puerto Rican, and white women. The adjusted odds of MLBW infants were elevated among Central and South American (OR, 1.14 [95% CI, 1.05-1.25]) and Puerto Rican women (OR, 1.41 [95% CI, 1.12-1.78]), relative to white women. CONCLUSIONS: The epidemiologic paradox of LBW in Latinos is valid. New conceptual models are needed to identify Latina women who are at risk for adverse pregnancy outcomes.     

Associations between congenital malformations and childhood cancer. A register-based case-control study

This report describes a population-based case-control study that aimed to assess and quantify the risk of children with congenital malformations developing cancer. Three sources of data were used: the Victorian Cancer Register, the Victorian Perinatal Data Register (VPDR) and the Victorian Congenital Malformations/Birth Defects Register. Cases included all Victorian children born between 1984 and 1993 who developed cancer. Four controls per case, matched on birth date, were randomly selected from the VPDR. Record linkage between registers provided malformation data. A matched case-control analysis was undertaken. Of the 632 cancer cases, 570 (90.2%) were linked to the VPDR. The congenital malformation prevalence in children with cancer was 9.6% compared with 2.5% in the controls [odds ratio (OR) 4.5, 95% CI 3.1-6.7]. A strong association was found with chromosomal defects (OR=16.7, 95% CI 6.1-45.3), in particular Down's syndrome (OR=27.1, 95% CI 6.0-122). Most other birth defect groups were also associated with increased cancer risk. The increased risk of leukaemia in children with Down's syndrome was confirmed, and children with central nervous system (CNS) defects were found to be at increased risk of CNS tumours. The report confirms that children with congenital malformations have increased risks of various malignancies. These findings may provide clues to the underlying aetiology of childhood cancer, as congenital malformations are felt to be a marker of exposures or processes which may increase cancer risk. The usefulness of record linkage between accurate population-based registers in the epidemiological study of disease has also been reinforced.     

Maternal use of antiepileptic drugs and the risk of major congenital malformations: a joint European prospective study of human teratogenesis associated with maternal epilepsy

PURPOSE: To quantify the risks of intrauterine antiepileptic drug (AED) exposure in monotherapy and polytherapy. METHODS: Data from five prospective European studies totaling 1,379 children were pooled and reanalyzed. Data were available for 1,221 children exposed to AED during pregnancy and for 158 children of unexposed control pregnancies. RESULTS: Overall, when comparing a subgroup of 192 children exposed to AED with 158 children of matched nonepileptic controls, there was an increased risk of major congenital malformations (MCA) in children exposed to AED during gestation [relative risk (RR) 2.3; 95% confidence interval (CI): 1.2-4.7]. A significant increase in risk was found for children exposed to valproate (VPA) (RR 4.9; 95% CI: 1.6-15.0) or carbamazepine (CBZ) (RR 4.9; 95% CI: 1.3-18.0) in monotherapy. When comparing different AED regimens during all 1,221 pregnancies, risks of MCA were significantly increased for the combination of phenobarbital (PB) and ethosuximide (RR 9.8; 95% CI: 1.4-67.3) and the combination of phenytoin, PB, CBZ, and VPA (RR 11.0; 95% CI: 2.1-57.6). Offspring of mothers using > 1,000 mg VPA/day were at a significantly increased risk of MCA, especially neural tube defects, compared to offspring exposed < or =600 mg VPA/day (RR 6.8; 95% CI: 1.4-32.7). No difference in risk of MCA was found between the offspring exposed to 601-1,000 mg/day and < or =600 mg/day. CONCLUSIONS: This reanalysis shows that VPA is consistently associated with an increased risk of MCA in babies born to mothers with epilepsy. Significant associations were also observed with CBZ. Larger prospective population-based studies are needed to evaluate the risks of many other less frequently prescribed treatment regimens, including newly marketed AEDs.     

Fetal thrombocytopenia and its relation to maternal thrombocytopenia

BACKGROUND: Neonates with severe thrombocytopenia can have bleeding leading to death or lifelong residual defects. The predictors, frequency, and consequences of fetal thrombocytopenia are not known, nor is it known if there are maternal clinical features that could predict fetal thrombocytopenia. METHODS: We conducted a seven-year cross-sectional study in which platelet counts were determined in newborns' umbilical-cord blood and blood obtained from their mothers at consecutive deliveries in one obstetrical unit. The relations of the umbilical-cord platelet count to maternal risk factors were determined. RESULTS: Platelet counts were determined in blood samples from 15,471 mothers and 15,932 newborn infants. The cord-blood platelet count was less than 50,000 per cubic millimeter in 19 infants (0.12 percent; 95 percent confidence interval, 0.07 to 0.19 percent), whereas the platelet count was less than 150,000 per cubic millimeter in 6.6 percent of the mothers (95 percent confidence interval, 6.2 to 7.0 percent). One infant among those born to 756 mothers with incidental thrombocytopenia, 5 infants among those born to 1414 mothers with hypertension, and 4 infants among those born to 46 mothers with idiopathic thrombocytopenic purpura had cord-blood platelet counts between 20,000 and 50,000 per cubic millimeter. Only 6 infants (0.04 percent; 95 percent confidence interval, 0.01 to 0.08 percent) had cord-blood platelet counts of less than 20,000 per cubic millimeter; all their mothers were among the 18 whose 19 fetuses were at risk for neonatal alloimmune thrombocytopenia. Two of these infants had in utero intracranial hemorrhage. In addition, 3 infants born to these 18 women had cord-blood platelet counts between 20,000 and 50,000 per cubic millimeter; there was 1 stillbirth due to intracranial hemorrhage. CONCLUSIONS: Moderate-to-severe fetal thrombocytopenia is a rare event. The only severely affected neonates with morbidity or mortality due to this condition are those born to mothers with antiplatelet alloantibodies.     

Biological control of nematode parasites of livestock in Fiji: screening of fresh dung of small ruminants for the presence of nematophagous fungi

OBJECTIVE: To assess risk factors and outcomes associated with nuchal cord at birth. STUDY DESIGN: A population-based, case-control study was conducted using linked birth and hospitalization records. Three thousand newborns were randomly selected from all singleton births with nuchal cord as noted on the birth record (n = 5,426) in King County, Washington, 1992-1993. For comparison, 3,000 controls were randomly selected from the 46,952 unaffected singleton births. RESULTS: An increased risk of nuchal cord was associated with induction of labor (odds ratio [OR] adjusted for maternal age and parity 2.0, 95% confidence interval [CI] 1.7-2.3), African American infant race (OR 1.3, 95% CI 1.0-1.6), primiparity (OR 1.2, 95% CI 1.0-1.5) and male sex (OR 1.2, 95% CI 1.0-1.3). After exclusion of selected obstetric complications, the risk of nuchal cord associated with induction of labor increased (OR 2.4, 95% CI 2.0-3.0). Nuchal cord was associated with increased risks of fetal distress (OR 2.7, 95% CI 2.1-3.4), meconium staining (OR 2.1, 95% CI 1.7-2.6), five-minute Apgar score < 7 (OR 1.6, 95% CI 1.1-2.4) and assisted ventilation < 30 minutes (OR 1.9, 95% CI 1.4-2.6). Although hospital charges for newborns with nuchal cord were slightly greater than for those without (P = .02), hospital lengths of stay did not differ significantly. CONCLUSION: Induction of labor was identified as an independent risk factor for nuchal cord. Certain adverse perinatal outcomes are increased in neonates with nuchal cord. However, neonates with nuchal cord do not have significantly longer neonatal hospital stays, and thus the adverse effects of nuchal cord may be transient.     

Primary intrasellar mixed germ-cell tumor with precocious puberty and diabetes insipidus

A case-control study using data from the Baltimore-Washington Infant Study (BWIS) examined possible paternal risk factors in the etiology of isolated membranous ventricular septal defects (VSD). There were 641 total VSD case infants and 3,549 randomly selected control infants ascertained between 1981 and 1989. Isolated membranous VSDs were identified in 499 cases. Socio-demographic factors (such as parental age and race), social habits, and medical conditions were analyzed by multiple logistic regression in order to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). Paternal age was not found to be a risk factor per se, but small positive associations were found for some social habits and maternal factors. Significant associations were found for paternal marijuana use (OR 1.36, 95% CI 1.05-1.76), African-American race of the infant (OR 1.34, 95% CI 1.09-1.65), and for cocaine use among older fathers (OR 3.92, 95% CI 1.30-11.86). These associations support a multifactorial etiologic hypothesis for isolated membranous VSDs and point to some interesting parental behavioral and medical considerations which may contribute to risk for this common birth defect.     

Evidence for an association between environmental tobacco smoke exposure and birthweight: a meta-analysis and new data

Because of the strong association of active smoking with fetal growth retardation, increasing interest has focused on whether there is also an association with exposure to environmental tobacco smoke (ETS). We examined this issue in a retrospective study and by conducting a review of the literature and data pooling. In our study, nonsmoking women with singleton livebirths born in 1986-87 (n = 992) provided information on exposure to ETS for 1 h or more per day and paternal smoking. The risk of low birthweight (LBW, < 2500 g) was not increased in infants of ETS-exposed women, but there was a somewhat increased risk for LBW at term (adjusted odds ratio [OR] 1.8, 95% confidence interval [CI] 0.6, 4.8) and small-for-gestational-age (< 10th percentile of weight; OR = 1.4, 95% CI = 0.8, 2.5). These results were in the range of 16 other studies in the literature that had odds ratios from 1.0 to 2.2. A weighted average of the results of all studies on LBW at term or small-for-gestational-age yielded a pooled estimate of 1.2 [95% CI = 1.1, 1.3] in nonsmoking women. The pooled estimate of mean birthweight indicated a decrement of 28 g with ETS exposure of nonsmoking women [95% CI = -41, -16], with a greater decrement (about 40 g) seen among more homogeneous studies.