Richard Dobbie

University of Cambridge, Cambridge, ENG, United Kingdom

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Publications (30)344.75 Total impact

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    ABSTRACT: OBJECTIVE: To determine whether relationships with gestational age and birthweight centile vary between specific causes of special educational need (SEN). DESIGN: Retrospective cohort study. SETTING: Scotland. POPULATION: A cohort of 407 503 schoolchildren. METHODS: Polytomous logistic regression was used to examine the risk of each cause of SEN across the spectrum of gestation at delivery and birthweight centile, adjusting for potential confounding factors. MAIN OUTCOME MEASURES: Crude and adjusted odds ratios and confidence intervals. RESULTS: Of the 19 821 children with SEN, 557 (2.8%) had sensory impairments, 812 (4.1%) had physical or motor disabilities, 876 (4.4%) had language impairments, 2823 (14.2%) had social, emotional, or behavioural problems, 7018 (35.4%) had intellectual disabilities, 4404 (22.2%) had specific learning difficulties, and 1684 (8.5%) autistic spectrum disorder (ASD). Extreme preterm delivery (at 24-27 weeks of gestation) was a strong predictor of sensory (adjusted OR 23.64, 95% CI 12.03-46.45), physical or motor (adjusted OR 29.69, 95% CI 17.49-50.40), and intellectual (adjusted OR 11.67, 95% CI 8.46-16.10) impairments, with dose relationships across the range of gestation. Similarly, birthweight below the third centile was associated with sensory (adjusted OR 2.85, 95% CI 2.04-3.99), physical or motor (adjusted OR 2.47, 95% CI 1.82-3.37), and intellectual (adjusted OR 2.67, 95% CI 2.41-2.96) impairments. Together, gestation and birthweight centile accounted for 24.0% of SEN arising from sensory impairment, 34.3% arising from physical or motor disabilities, and 26.6% arising from intellectual disabilities. Obstetric factors were less strongly associated with specific learning difficulties and social or emotional problems, and there were no significant associations with ASD. CONCLUSIONS: The association between gestation and birthweight centile and overall risk of SEN is largely driven by very strong associations with sensory, physical or motor impairments, and intellectual impairments.
    BJOG An International Journal of Obstetrics & Gynaecology 11/2012; · 3.76 Impact Factor
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    ABSTRACT: Previous studies have demonstrated an association between preterm delivery and increased risk of special educational need (SEN). The aim of our study was to examine the risk of SEN across the full range of gestation. We conducted a population-based, retrospective study by linking school census data on the 407,503 eligible school-aged children resident in 19 Scottish Local Authority areas (total population 3.8 million) to their routine birth data. SEN was recorded in 17,784 (4.9%) children; 1,565 (8.4%) of those born preterm and 16,219 (4.7%) of those born at term. The risk of SEN increased across the whole range of gestation from 40 to 24 wk: 37-39 wk adjusted odds ratio (OR) 1.16, 95% confidence interval (CI) 1.12-1.20; 33-36 wk adjusted OR 1.53, 95% CI 1.43-1.63; 28-32 wk adjusted OR 2.66, 95% CI 2.38-2.97; 24-27 wk adjusted OR 6.92, 95% CI 5.58-8.58. There was no interaction between elective versus spontaneous delivery. Overall, gestation at delivery accounted for 10% of the adjusted population attributable fraction of SEN. Because of their high frequency, early term deliveries (37-39 wk) accounted for 5.5% of cases of SEN compared with preterm deliveries (<37 wk), which accounted for only 3.6% of cases. Gestation at delivery had a strong, dose-dependent relationship with SEN that was apparent across the whole range of gestation. Because early term delivery is more common than preterm delivery, the former accounts for a higher percentage of SEN cases. Our findings have important implications for clinical practice in relation to the timing of elective delivery.
    PLoS Medicine 06/2010; 7(6):e1000289. · 15.25 Impact Factor
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    ABSTRACT: To estimate the relationship between maternal serum levels of placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) in early pregnancy with the risk of subsequent adverse outcome. A nested, case-control study was performed within a prospective cohort study of Down syndrome screening. Maternal serum levels of sFlt-1 and PlGF at 10-14 weeks of gestation were compared between 939 women with complicated pregnancies and 937 controls. Associations were quantified as the odds ratio for a one decile increase in the corrected level of the analyte. Higher levels of sFlt-1 were not associated with the risk of preeclampsia but were associated with a reduced risk of delivery of a small for gestational age infant (odds ratio [OR] 0.92, 95% confidence interval [CI] 0.88-0.96), extreme (24-32 weeks) spontaneous preterm birth (OR 0.90, 95% CI 0.83-0.99), moderate (33-36 weeks) spontaneous preterm birth (OR 0.93, 95% CI 0.88-0.98), and stillbirth associated with abruption or growth restriction (OR 0.77, 95% CI 0.61-0.95). Higher levels of PlGF were associated with a reduced risk of preeclampsia (OR 0.95, 95% CI 0.90-0.99) and delivery of a small for gestational age infant (OR 0.95, 95% CI 0.91-0.99). Associations were minimally affected by adjustment for maternal characteristics. Higher early pregnancy levels of sFlt-1 and PlGF were associated with a decreased risk of adverse perinatal outcome.
    Obstetrics and Gynecology 07/2007; 109(6):1316-24. · 4.80 Impact Factor
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    ABSTRACT: To determine whether maternal serum levels of alphafetoprotein (alpha-FP) and human chorionic gonadotrophin (hCG) at 15-21 weeks provided clinically useful prediction of stillbirth in first pregnancies. Retrospective study of record linkage of a regional serum screening laboratory to national registries of pregnancy outcome and perinatal death. West of Scotland, 1992-2001. A total of 84,769 eligible primigravid women delivering an infant at or beyond 24 weeks of gestation. The risk of stillbirth between 24 and 43 weeks was assessed using the Cox proportional hazards model. Logistic regression models within gestational windows were then used to estimate predicted probability. Screening performance was assessed as area under the receiver operating characteristic (ROC) curve. Antepartum stillbirth unrelated to congenital abnormality. The odds ratio (95% CI) for stillbirth at 24-28 weeks for women in the top 1% were 11.97 (5.34-26.83) for alpha-FP and 5.80 (2.19-15.40) for hCG. The corresponding odds ratios for stillbirth at or after 37 weeks were 2.44 (0.74-8.10) and 0.79 (0.11-5.86), respectively. Adding biochemical to maternal data increased the area under the ROC curve from 0.66 to 0.75 for stillbirth between 24 and 28 weeks but only increased it from 0.64 to 0.65 for stillbirth at term and post-term. Women in the top 5% of predicted risk had a positive likelihood ratio of 7.8 at 24-28 weeks, 3.7 at 29-32 weeks, 5.1 at 33-36 weeks and 3.4 at 37-43 weeks, and the corresponding positive predictive values were 0.97, 0.33, 0.47 and 0.63%, respectively. Maternal serum levels of alpha-FP and hCG were statistically associated with stillbirth risk. However, the predictive ability was generally poor except for losses at extreme preterm gestations, where prevention may be difficult and interventions have the potential to cause significant harm.
    BJOG An International Journal of Obstetrics & Gynaecology 07/2007; 114(6):705-14. · 3.76 Impact Factor
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    ABSTRACT: We sought to determine the association between maternal body mass index and risk of preterm delivery. We assessed 187,290 women in Scotland and estimated adjusted odds ratios for spontaneous and elective preterm deliveries among overweight, obese, and morbidly obese women relative to normal-weight women. Among nulliparous women, the risk of requiring an elective preterm delivery increased with increasing BMI, whereas the risk of spontaneous preterm labor decreased. Morbidly obese nulliparous women were at increased risk of all-cause preterm deliveries, neonatal death, and delivery of an infant weighing less than 1000 g who survived to 1 year of age (a proxy for severe long-term disability). By contrast, obesity and elective preterm delivery were only weakly associated among multiparous women. Obese nulliparous women are at increased risk of elective preterm deliveries. This in turn leads to an increased risk of perinatal mortality and is likely to lead to increased risks of long-term disability among surviving offspring.
    American Journal of Public Health 02/2007; 97(1):157-62. · 3.93 Impact Factor
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    ABSTRACT: Women with a previous stillbirth are known to be at increased risk of stillbirth in subsequent pregnancies. However, few studies have addressed the association between other complications of pregnancy and the future risk of stillbirth. Using linkage of national pregnancy and perinatal death registries, the authors performed a retrospective cohort study of 133,163 women having a second birth in Scotland between 1992 and 2001 whose first infant was liveborn. The risk of unexplained stillbirth was increased among women with a previous preterm birth (adjusted hazard ratio (HR) = 2.04, 95% confidence interval (CI): 1.34, 3.11), previous delivery of a small for gestational age (SGA) infant (HR = 2.14, 95% CI: 1.59, 2.87), and previous preeclampsia (HR = 1.68, 95% CI: 1.07, 2.62). The associations were similar after adjustment for maternal age, height, marital and smoking status, and interpregnancy interval. There was a statistically significant positive interaction between previous delivery of a SGA infant and previous preeclampsia (p = 0.01): Women with this combination in their first pregnancy had an approximately fivefold risk of unexplained stillbirth in the second pregnancy (HR = 4.95, 95% CI: 2.63, 9.32). Associations were stronger with SGA unexplained stillbirths. The authors conclude that complicated first births of liveborn infants are associated with an increased risk of unexplained stillbirth in the next pregnancy.
    American Journal of Epidemiology 02/2007; 165(2):194-202. · 4.78 Impact Factor
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    ABSTRACT: Nulliparous women are at increased risk of spontaneous preterm birth. Other maternal and biochemical risk factors have also been described. However, it is unclear whether these associations are strong enough to offer clinically useful prediction. It is also unclear whether the predictive power of these factors varies in relation to the degree of prematurity. The risk of spontaneous preterm birth associated with maternal characteristics and second trimester serum screening data was analysed in a dataset of 84 391 first births in Scotland between 1992 and 2001 using Cox and logistic regression. Variation in the relative risk of preterm birth over the period 24-36 weeks was assessed using a test of the proportional hazards assumption. The risk of spontaneous preterm birth was positively associated with maternal serum levels of alpha-fetoprotein, socioeconomic deprivation, number of previous therapeutic abortions, smoking, and being unmarried and was negatively associated with height and body mass index. The risk of preterm birth at 24-28 weeks, but not later gestations, was increased in association with maternal levels of human chorionic gonadotrophin >95th percentile, maternal age <20, and two or more previous miscarriages. The area under the receiver operating characterise curve (95% CI) for models based on these factors was 0.67 (0.63-0.71) for 24-28 weeks, 0.65 (0.62-0.68) for 29-32 weeks, and 0.62 (0.61-0.63) for 33-36 weeks. Time to event analytic methods can identify factors that are differentially associated with spontaneous preterm birth according to the degree of prematurity. However, models based on maternal and biochemical data perform poorly as a screening test for any degree of spontaneous preterm birth.
    International Journal of Epidemiology 10/2006; 35(5):1169-77. · 6.98 Impact Factor
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    ABSTRACT: To describe the association between pregnancy associated plasma protein A (PAPP-A), alpha-fetoprotein (AFP) and adverse perinatal outcome. We conducted a multicenter prospective cohort study of 8,483 women attending for prenatal care in southern Scotland between 1998 and 2000. The risk of delivering a small for gestational age infant, delivering preterm, and stillbirth were related to maternal serum levels of PAPP-A and AFP. Women with a low PAPP-A were not more likely to have elevated levels of AFP. Compared with women with a normal PAPP-A and a normal AFP, the odds ratio for delivering a small for gestational age infant for women with a high AFP was 0.9 (95% confidence interval [CI] 0.5-1.6), for women with a low PAPP-A was 2.8 (95% CI 2.0-4.0), and for women with both a high AFP and a low PAPP-A was 8.5 (95% CI 3.6-20.0). The odds ratio for delivering preterm for women with a high AFP was 1.8 (95% CI 1.3-2.7), for women with a low PAPP-A was 1.9 (95% CI 1.3-2.7), and for women with both a low PAPP-A and a high AFP was 9.9 (95% CI 4.4-22.0). These interactions were statistically significant for both outcomes (P = .03 and .04, respectively). There was a nonsignificant trend toward a similar interaction in relation to stillbirth risk. Of the women with the combination of a low PAPP-A and high AFP, 32.1% (95% CI 15.9-52.4) delivered a low birth weight infant. Low maternal serum levels of PAPP-A between 10 and 14 weeks and high levels of AFP between 15 and 21 weeks gestation are synergistically associated with adverse perinatal outcome. II-2.
    Obstetrics and Gynecology 02/2006; 107(1):161-6. · 4.80 Impact Factor
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    ABSTRACT: To determine whether cesarean delivery is independently associated with later subfertility. Retrospective cohort study. Maternity records kept for Scotland, 1980-1999. The study included 109,991 women who had first births between 1980 and 1984, excluding multiple or preterm births and perinatal deaths. Exposures studied were spontaneous vaginal birth, operative vaginal birth, planned cesarean delivery for breach presentation, planned cesarean delivery for other indications, and emergency cesarean delivery. The relative risk of not having a second pregnancy over the following 15 years, the interpregnancy interval, and the number of spontaneous early pregnancy losses between the first and second birth. Women who delivered by planned cesarean section for breech presentation had an increased risk of not having a second birth compared with women whose first birth was a spontaneous vertex delivery (relative risk [RR]: 1.21, 95% confidence interval [CI]: 1.14 to 1.29). However, after adjustment for maternal and obstetric characteristics, there was no longer a strong association (adjusted RR: 1.07, 95% CI: 1.00 to 1.15). Operative vaginal delivery (forceps and vacuum extraction) and all types of cesarean delivery were associated with longer interpregnancy intervals. There was no relationship between mode of delivery and the number of spontaneous early pregnancy losses between the first and second birth. It is unlikely that delivering by cesarean section in a first pregnancy decreases a woman's likelihood of having a second viable pregnancy.
    Fertility and sterility 02/2006; 85(1):90-5. · 3.97 Impact Factor
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    ABSTRACT: The likelihood of recurrence of sudden infant death syndrome (SIDS) is an issue of biological, clinical, and legal interest. Obstetric complications are associated with an increased risk of SIDS and are likely to recur in subsequent pregnancies. We postulated that women whose infants died from SIDS would be more likely to have had obstetric complications in their other pregnancies. We linked national UK databases of maternity-hospital discharges, perinatal deaths, and death certifications. We studied 258 096 women who had consecutive births in Scotland between 1985 and 2001. Women who had an infant who died from SIDS were at increased risk in their next pregnancy of delivering an infant small for gestational age (odds ratio 2.27, 95% CI 1.54-3.34, p<0.0001) and of preterm birth (2.53, 1.82-3.53, p<0.0001). The risk of SIDS was higher for the children of women whose previous infant had been small for gestational age (1.87, 1.19-2.94, p=0.007) or preterm (1.93, 1.24-3.00, p=0.004). Multivariate analysis showed that all associations were explained by common maternal risk factors for SIDS and obstetric complications and by the likelihood of recurrence of fetal growth restriction and preterm birth. Women whose infants die from SIDS are more likely to have complications in their other pregnancies. Recurrence of pregnancy complications predisposing to SIDS could partly explain why some women have recurrent SIDS.
    The Lancet 01/2006; 366(9503):2107-11. · 39.21 Impact Factor
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    ABSTRACT: There is currently no validated method for antepartum prediction of the risk of failed vaginal birth after cesarean section and no information on the relationship between the risk of emergency cesarean delivery and the risk of uterine rupture. We linked a national maternity hospital discharge database and a national registry of perinatal deaths. We studied 23,286 women with one prior cesarean delivery who attempted vaginal birth at or after 40-wk gestation. The population was randomly split into model development and validation groups. The factors associated with emergency cesarean section were maternal age (adjusted odds ratio [OR] = 1.22 per 5-y increase, 95% confidence interval [CI]: 1.16 to 1.28), maternal height (adjusted OR = 0.75 per 5-cm increase, 95% CI: 0.73 to 0.78), male fetus (adjusted OR = 1.18, 95% CI: 1.08 to 1.29), no previous vaginal birth (adjusted OR = 5.08, 95% CI: 4.52 to 5.72), prostaglandin induction of labor (adjusted OR = 1.42, 95% CI: 1.26 to 1.60), and birth at 41-wk (adjusted OR = 1.30, 95% CI: 1.18 to 1.42) or 42-wk (adjusted OR = 1.38, 95% CI: 1.17 to 1.62) gestation compared with 40-wk. In the validation group, 36% of the women had a low predicted risk of caesarean section (< 20%) and 16.5% of women had a high predicted risk (> 40%); 10.9% and 47.7% of these women, respectively, actually had deliveries by caesarean section. The predicted risk of caesarean section was also associated with the risk of all uterine rupture (OR for a 5% increase in predicted risk = 1.22, 95% CI: 1.14 to 1.31) and uterine rupture associated with perinatal death (OR for a 5% increase in predicted risk = 1.32, 95% CI: 1.02 to 1.73). The observed incidence of uterine rupture was 2.0 per 1,000 among women at low risk of cesarean section and 9.1 per 1,000 among those at high risk (relative risk = 4.5, 95% CI: 2.6 to 8.1). We present the model in a simple-to-use format. We present, to our knowledge, the first validated model for antepartum prediction of the risk of failed vaginal birth after prior cesarean section. Women at increased risk of emergency caesarean section are also at increased risk of uterine rupture, including catastrophic rupture leading to perinatal death.
    PLoS Medicine 10/2005; 2(9):e252. · 15.25 Impact Factor
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    ABSTRACT: To determine the risk of perinatal death among twins born at term in relation to mode of delivery. Retrospective cohort study. Scotland 1985-2001. All twin births at or after 36 weeks of gestation, excluding antepartum stillbirths and perinatal deaths due to congenital abnormality (n= 8073). The outcome of first and second twins was compared using McNemar's test and the outcome of twin pairs in relation to mode of delivery was compared using exact logistic regression. Intrapartum stillbirth or neonatal death of either twin. Overall, there were six deaths of first twins and 30 deaths of second twins (OR for second twin 5.00, 95% CI 2.00-14.70). The odds ratio for death of the second twin due to intrapartum anoxia was 21 (95% CI 3.4-868.5). The associations were similar for twins delivered following induction of labour and for sex discordant twins. However, there was no association between birth order and the risk of death among 1472 deliveries by planned caesarean section. There was death of either twin among 2 of 1472 (0.14%) deliveries by planned caesarean section and 34 of 6601 (0.52%) deliveries by other means (P= 0.05, odds ratio for planned caesarean section 0.26 [95% CI 0.03-1.03]). The association was similar when adjusted for potential confounders. Assuming causality, we estimate that 264 caesarean deliveries (95% CI 158-808) would be required to prevent each death. Planned caesarean section may reduce the risk of perinatal death of twins at term by approximately 75% compared with attempting vaginal birth. This is principally due to reducing the risk of death of the second twin due to intrapartum anoxia.
    BJOG An International Journal of Obstetrics & Gynaecology 09/2005; 112(8):1139-44. · 3.76 Impact Factor
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    ABSTRACT: To assess the risk of breast cancer in patients with a previous history of miscarriage or induced abortion. Case-control study relating "exposure" to outcome by linkage of national hospital discharge and maternity records, the national cancer registry, and death records. Scotland. Miscarriage analysis-2828 women with breast cancer and 9781 matched controls; induced abortion analysis-2833 women with breast cancer and 9888 matched controls. After stratification for age at diagnosis, parity, and age at first birth, the odds ratio (95% confidence intervals) of breast cancer was 1.02 (0.88 to 1.18) in women with a previous miscarriage, and 0.80 (0.72 to 0.89) in women with a previous induced abortion. Further adjustments for age at bilateral oophorectomy, socioeconomic status (based on small area of residence), and health board area of residence had only minor effects on these odds ratios. These data do not support the hypothesis that miscarriage or induced abortion represent substantive risk factors for the future development of breast cancer.
    Journal of Epidemiology &amp Community Health 05/2005; 59(4):283-7. · 3.39 Impact Factor
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    ABSTRACT: Preterm birth and low birth weight are determined, at least in part, during the first trimester of pregnancy. However, it is unknown whether the risk of stillbirth is also determined during the first trimester. To determine whether the risk of antepartum stillbirth varies in relation to circulating markers of placental function measured during the first trimester of pregnancy. Multicenter, prospective cohort study (conducted in Scotland from 1998 through 2000) of 7934 women who had singleton births at or after 24 weeks' gestation, who had blood taken during the first 10 weeks after conception, and who were entered into national registries of births and perinatal deaths. Antepartum stillbirths and stillbirths due to specific causes. There were 8 stillbirths among the 400 women with levels of pregnancy-associated plasma protein A (PAPP-A) in the lowest fifth percentile compared with 17 among the remaining 7534 women (incidence rate per 10,000 women per week of gestation: 13.4 vs 1.4, respectively; hazard ratio [HR], 9.2 [95% confidence interval [CI], 4.0-21.4]; P<.001). When analyzed by cause of stillbirth, low level of PAPP-A was strongly associated with stillbirth due to placental dysfunction, defined as abruption or unexplained stillbirth associated with growth restriction (incidence rate: 11.7 vs 0.3, respectively; HR, 46.0 [95% CI, 11.9-178.0]; P<.001), but was not associated with other causes of stillbirth (incidence rate: 1.7 vs 1.1, respectively; HR, 1.4 [95% CI, 0.2-10.6]; P = .75). There was no relationship between having a low level of PAPP-A and maternal age, ethnicity, parity, height, body mass index, race, or marital status. Adjustment for maternal factors did not attenuate the strength of associations observed. There was no association between maternal circulating levels of the free beta subunit of human chorionic gonadotropin and stillbirth risk. The risk of stillbirth in late pregnancy may be determined by placental function in the first 10 weeks after conception.
    JAMA The Journal of the American Medical Association 11/2004; 292(18):2249-54. · 29.98 Impact Factor
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    ABSTRACT: To determine whether neonatal respiratory morbidity at term is associated with an increased risk of later asthma and whether this may explain previously described associations between caesarean delivery and asthma. Retrospective cohort study using Scottish Morbidity Record (SMR) data of maternity (SMR02), neonatal (SMR11), and acute hospital (SMR01) discharges. Scotland. All singleton births at term between 1992-1995 in 23 Scottish maternity hospitals. Hospital admission with a diagnosis of asthma in the principal position between 1992 and 2000. Children who had a diagnosis of transient tachypnoea of the newborn or respiratory distress syndrome were at increased risk of being admitted to hospital with a diagnosis of asthma (hazard ratio (HR) 1.7, 95% confidence interval (95% CI) 1.4 to 2.2, p<0.001). This association was observed both among children delivered vaginally (HR 1.5, 95% CI 1.1 to 2.0, p = 0.007) and among those delivered by caesarean section (HR 2.2, 95% CI 1.6 to 3.0, p<0.001). In the absence of neonatal respiratory morbidity, delivery by caesarean section was weakly associated with the risk of asthma in childhood (HR 1.1, 95% CI 1.0 to 1.2, p = 0.004). The strengths of the associations were similar whether the caesarean delivery was planned or emergency and were not significantly altered by adjustment for maternal, obstetric, and other neonatal characteristics. Neonatal respiratory morbidity at term is associated with an increased risk of asthma in childhood which may explain previously described associations between caesarean delivery and later asthma.
    Archives of Disease in Childhood 11/2004; 89(10):956-60. · 3.05 Impact Factor
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    ABSTRACT: Unexplained stillbirth and the sudden infant death syndrome (SIDS) share some features. A raised maternal serum level of alpha-fetoprotein during the second trimester of pregnancy is a marker of placental dysfunction and a strong predictor of the risk of unexplained stillbirth. It is unknown whether alpha-fetoprotein levels also predict the risk of SIDS. We linked a prenatal-screening database for women in western Scotland with databases of maternity, perinatal death, and birth and death certifications to assess the association between second-trimester levels of maternal serum alpha-fetoprotein and the subsequent risk of SIDS. Among 214,532 women with singleton births, there were 114 cases of SIDS (incidence, 2.7 per 10,000 births among women with alpha-fetoprotein levels in the lowest quintile and 7.5 per 10,000 births among those with levels in the highest quintile). When the lowest quintile was used as a referent, the unadjusted odds ratios for SIDS for the second through fifth quintiles were 1.7 (95 percent confidence interval, 0.8 to 3.5), 1.8 (95 percent confidence interval, 0.9 to 3.7), 2.5 (95 percent confidence interval, 1.3 to 4.8), and 2.8 (95 percent confidence interval, 1.4 to 5.4), respectively (P for trend = 0.001). The risk of SIDS varied inversely with the birth-weight percentile and the gestational age at delivery; after adjustment for these factors, the odds ratios for SIDS were 1.7 (95 percent confidence interval, 0.8 to 3.5), 1.7 (95 percent confidence interval, 0.8 to 3.5), 2.2 (95 percent confidence interval, 1.1 to 4.4), and 2.2 (95 percent confidence interval, 1.1 to 4.3), respectively (P for trend = 0.01). There is a direct association between second-trimester maternal serum alpha-fetoprotein levels and the risk of SIDS, which may be mediated in part through impaired fetal growth and preterm birth.
    New England Journal of Medicine 10/2004; 351(10):978-86. · 54.42 Impact Factor
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    ABSTRACT: To determine the factors associated with an increased risk of perinatal death related to uterine rupture during attempted vaginal birth after caesarean section. Population based retrospective cohort study. Data from the linked Scottish Morbidity Record and Stillbirth and Infant Death Survey of births in Scotland, 1985-98. All women with one previous caesarean delivery who gave birth to a singleton infant at term by a means other than planned repeat caesarean section (n = 35 854). All intrapartum uterine rupture and uterine rupture resulting in perinatal death (that is, death of the fetus or neonate). The overall proportion of vaginal births was 74.2% and of uterine rupture was 0.35%. The risk of intrapartum uterine rupture was higher among women who had not previously given birth vaginally (adjusted odds ratio 2.5, 95% confidence interval 1.6 to 3.9, P < 0.001) and those whose labour was induced with prostaglandin (2.9, 2.0 to 4.3, P < 0.001). Both factors were also associated with an increased risk of perinatal death due to uterine rupture. Delivery in a hospital with < 3000 births a year did not increase the overall risk of uterine rupture (1.1, 0.8 to 1.5, P = 0.67). However, the risk of perinatal death due to uterine rupture was significantly higher in hospitals with < 3000 births a year (one per 1300 births) than in hospitals with >or= 3000 births a year (one per 4700; 3.4, 1.0 to 14.3, P = 0.04). Women who have not previously given birth vaginally and those whose labour is induced with prostaglandin are at increased risk of uterine rupture when attempting vaginal birth after caesarean section. The risk of consequent death of the infant is higher in units with lower annual numbers of births.
    BMJ (online) 09/2004; 329(7462):375. · 17.22 Impact Factor
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    ABSTRACT: Considerable debate exists on the epidemiology of genital anomalies. All genital anomalies, excluding undescended testes, were identified from neonatal returns, stillbirth and infant death survey records, and returns relating to hospital admissions and linked to form infant profiles on a cohort of singleton births between 1988 and 1997 with follow up for a minimum of three years. The mean genital anomaly prevalence rate in Scotland was calculated at 4.6 per 1000 births varying from 4.0 per 1000 births in 1988 to 5.9 per 1000 births in 1996. However, there was no evidence of a clear trend to an increasing prevalence of hypospadias, which constituted 73% of the anomalies studied. Logistic regression analysis of the data also showed this rate to be independently associated with being relatively small for gestational age (odds ratio (OR) 1.43, p < 0.001) and increasing maternal age (OR 1.2, p < 0.05). Infants born in deprived areas, as judged by the Carstairs deprivation score, were least likely to have a genital anomaly (OR 0.73, p < 0.01). A new linked register of congenital genital anomalies in Scotland suggests that over a decade, the birth prevalence of genital anomalies has changed little. The associations between genital anomalies, maternal age, and socioeconomic deprivation require further study.
    Archives of Disease in Childhood - Fetal and Neonatal Edition 03/2004; 89(2):F149-51. · 3.45 Impact Factor
  • GC Smith, J Pell, R Dobbie
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    ABSTRACT: Summary Background Caesarean section is associated with an increased risk of disorders of placentation in subsequent pregnancies, but effects on the rate of antepartum stillbirth are unknown. We aimed to establish whether previous caesarean delivery is associated with an increased risk of antepartum stillbirth. Methods We linked pregnancy discharge data from the Scottish Morbidity Record (1980-98) and the Scottish Stillbirth and Infant Death Enquiry (1985-98). We estimated the relative risk of antepartum stillbirth in second pregnancies using time- to-event analyses. Findings For 120 633 singleton second births, there were 68 antepartum stillbirths in 17 754 women previously delivered by caesarean section (2·39 per 10 000 women per week) and 244 in 102 879 women previously delivered vaginally (1·44; p
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    Heart (British Cardiac Society) 11/2003; 89(10):1249-50. · 5.01 Impact Factor