Maternal haemoglobin concentrations before and during pregnancy and stillbirth risk: A population-based case-control study

Background: Results of previous studies on the association between maternal haemoglobin concentration during pregnancy and stillbirth risk are inconclusive. It is not clear if haemoglobin concentration before pregnancy has a role. Using prospectively collected information from pre-pregnancy and antenatal visits, we investigated associations of maternal haemoglobin concentrations before and during pregnancy and haemoglobin dilution with stillbirth risk. Methods: In a population-based case-control study from rural Golestan, a province in northern Iran, we identified 495 stillbirths (cases) and randomly selected 2,888 control live births among antenatal health-care visits between 2007 and 2009. Using logistic regression, we estimated associations of maternal haemoglobin concentrations, haemoglobin dilution at different stages of pregnancy, with stillbirth risk. Results: Compared with normal maternal haemoglobin concentration (110-120g/l) at the end of the second trimester, high maternal haemoglobin concentration (≥140g/l) was associated with a more than two-fold increased stillbirth risk (OR = 2.31, 95% CI [1.30-4.10]), while low maternal haemoglobin concentration (<110g/l) was associated with a 37% reduction in stillbirth risk. Haemoglobin concentration before pregnancy was not associated with stillbirth risk. Decreased haemoglobin concentration, as measured during pregnancy (OR = 0.61, 95% CI [0.46, 0.80]), or only during the second trimester (OR = 0.75, 95% CI [0.62, 0.90]), were associated with reduced stillbirth risk. The associations were essentially similar for preterm and term stillbirths. Conclusions: Haemoglobin concentration before pregnancy is not associated with stillbirth risk. High haemoglobin level and absence of haemoglobin dilution during pregnancy could be considered as indicators of a high-risk pregnancy. © 2016 The Author(s)

Placental weight and mortality in premenopausal breast cancer by tumor characteristics

Placental weight may be regarded as an indirect marker of hormone exposures during pregnancy. There is epidemiological evidence that breast cancer mortality in premenopausal women increases with placental weight in the most recent pregnancy. We investigated if this association differs by tumor characteristics, including expression of estrogen and progesterone receptors. In a Swedish population-based cohort, we followed 1,067 women with premenopausal breast cancer diagnosed from 1992 to 2006. Using Cox regression models, we estimated hazard ratios for the association between placental weight and risk of premenopausal breast cancer mortality. In stratified analyses, we estimated mortality risks in subjects with different tumor stages, estrogen receptor (ER) or progesterone receptor (PR) status. Compared with women with placental weight less than 600 g, women with a placental weight between 600 and 699 g were at a 50 % increased risk of mortality, however, not significant change in risk was observed for women with placental weight �700 g. Mortality risks associated with higher placental weight were more pronounced among ER- and PR- breast cancer tumors, where both a placental weight 600-699 g and �700 g were associated with a more than doubled mortality risks compared with tumors among women with placental weight less than 600 g. Moreover, stratified analyses for joint receptor status revealed that a consistent increased mortality risk by placental weight was only apparent in women with ER-/PR- breast cancer. The increased mortality risk in premenopausal breast cancer associated with higher placental weight was most pronounced among ER- and PR- tumors. © 2012 Springer Science+Business Media New York

Consanguineous marriage, prepregnancy maternal characteristics and stillbirth risk: A population-based case-control study

Introduction. Consanguineous marriage is associated with increased risks for congenital anomalies, low birthweight, and other adverse perinatal outcomes. In this population-based, case-control study we investigated the association between consanguineous marriage (first-cousin marriage) and stillbirth risk, using prospectively collected information from prepregnancy visits. Material and methods. From 2007 to 2009, we identified 283 stillbirths (cases) and 2088 randomly selected live control births through prepregnancy visits in rural Golestan, Iran. The associations between consanguinity and prepregnancy maternal characteristics and stillbirth risk were examined using multivariate logistic regression. Results. The rate of consanguineous marriage was 19.4% among cases and 13.6% among controls. Consanguinity was associated with increased stillbirth risk [odds ratio (OR) 1.53; 95% CI 1.10-2.14]. The association was significantly increased for preterm stillbirth (< 37 gestational weeks) (OR 2.43; 95% CI 1.46-4.04) but not for term stillbirth (≥ 37 weeks) (OR 1.14; 95% CI 0.75-1.74). Low and high maternal age, underweight, obesity, nulliparity, a history of infertility or miscarriage, previous obstetric complications (preeclampsia, preterm delivery, and stillbirth in previous pregnancies) were also associated with increased stillbirth risks. Conclusions. Consanguineous marriage is associated with increased risk of stillbirth, particularly preterm stillbirth. Findings for other maternal risk factors for stillbirth in rural Iran are consistent with previously reported findings from high-income countries. © 2015 Nordic Federation of Societies of Obstetrics and Gynecology

Severe asphyxia due to delivery-related malpractice in Sweden 1990–2005

Aim The objective of the thesis was to describe the most common causes of substandard care during labour contributing to severe asphyxia or neonatal death, to study risk factors related to asphyxia associated with substandard care and to explore the occurrence of substandard care during labour. Background There are about 100 000 infants born every year in Sweden. Most infants are born healthy after uncomplicated deliveries. However, 20-50 claims for financial compensation are made annually to the Patients Advisory Committee (PA C) on suspicion that substandard care during labour has contributed to severe asphyxia causing cerebral palsy or death. Even if this group of patients is notably small, asphyxia causes life-long impairment and immeasurable suffering to the patients and their families. In addition, the insurance costs are substantial and amount to 25% of all costs related to substandard care in Sweden. With the exception of this group of patients, and claims to the Health Services Disciplinary Board, the frequency of substandard care in relation to childbirth is fairly unknown. Material and methods Inclusion criteria were pregnancies with a gestational length ≥ 33 weeks, a spontaneous or induced start of labour, a normal CTG at admission for labour, and Apgar score < 7 at 5 minutes of age (Papers I-IV). 472 case records of deliveries from 1990-2005, filed at the PAC were scrutinised. In Paper I and II the deliveries and acts of neonatal resuscitation procedures are described. In Paper III, maternal characteristics, factors related to care and infant characteristics for patients receiving lifelong financial compensation from PAC are compared with all infants with full Apgar score at 5 minutes of age born after a vaginal start during the same time period in Sweden (n=1.141 059). In Paper IV deliveries and risk factors from 313 infants with Apgar score < 7at 5 minutes of age, born in the Stockholm County are compared with 313 infants with full Apgar score at five minutes of age, matched for year of birth. Results One-hundred and seventy-seven infants were considered to have been severely asphyxiated due to substandard care during labour (Paper I-III). The most common occurrences of malpractice in conjunction with labour were neglecting to supervise fetal well-being (98%), neglecting signs of fetal asphyxia (71%), including incautious use of oxytocin (71%) and choosing a non-optimal mode of delivery (52%) (Paper I). Resuscitation of the 177 severely asphyxiated infants was unsatisfactory in 47%. The most important flaw was the defective compliance with the guidelines concerning ventilation and prompt paging for skilled personnel in cases of imminent asphyxia (Paper II). Risk factors associated with asphyxia included maternal age ≥ 30 years, short maternal stature (< 159 cm), previous caesarean delivery, insulin-dependent diabetes, induced deliveries and night deliveries, where the increases in risk were doubled to a four-fold. In addition, dystocia of labour was associated with a five-fold increase in risk, which was further increased if epidural anaesthesia or opioids were used. Small- and large-for-gestational age infants, post-term (> 42 weeks) births, twins and breech deliveries had a three to eight-fold increase in risk of asphyxia when there was substandard care during labour (Paper III). Two thirds of infants born in the Stockholm region 2004-2006, with Apgar score < 7 at 5 minutes but also one third of the healthy controls were subjected to some kind of substandard care during labour (Paper IV). The main causes of substandard care during labour were related to misinterpretation of CTG, not acting timely on abnormal CTG, and incautious use of oxytocin. The risk of asphyxia increased with duration of abnormal CTG and was increased fifteen-fold when this was abnormal for ≥ 90 minutes. Oxytocin was provided without sign of inertia in 20% of cases and controls and the risk of asphyxia was increased more than fivefold in cases of tachysystole. Infants born after a spontaneous vaginal delivery with abnormal CTG for more than 45 minutes had a more than sevenfold risk of low Apgar score. In instrumental deliveries that were considered complex, there was a more than seventeen-fold risk of an Apgar score < 7 at 5 minutes of age. Assuming that substandard care is causative for low Apgar score, we estimate that 42% of the cases could be prevented by avoiding substandard care (Paper IV). Conclusion It is possible to improve patient safety during labour by applying educational efforts on fetal surveillance and increasing awareness of risk factors associated with asphyxia. The main causes of substandard care during labour are related to misinterpretation of CTG, not acting timely on abnormal CTG, misinterpretation of guidelines and misuse of oxytocin. Low Apgar score at 5 minutes of age can substantially, be prevented by avoiding substandard care

Breast cancer risk in opposite-sexed twins: Influence of birth weight and co-twin birth weight

Most, but not all, studies report a positive association between birth weight, as an indirect marker of prenatal hormone exposure, and offspring breast cancer risk, particularly premenopausal breast cancer. Females from opposite-sexed twin pairs may also be prenatally exposed to androgens from their twin brothers. A Swedish study of opposite-sexed twins with a small sample size found a very strong positive association between female birth weight and breast cancer risk. In this case-control study, nested within a cohort of female opposite-sexed twins, we included 543 breast cancer case subjects diagnosed in the period from 1972 to 2008 and 2715 matched control subjects. Conditional logistic regression estimated the breast cancer risk associated with birth weight and other birth characteristics, including gestational age and co-twin birth weight. All statistical tests were two-sided. There was no association between birth weight (odds ratio = 1.01; 95% confidence interval = 0.70 to 1.46) or twin brother's birth weight and risk of breast cancer, which suggests the previously reported strong positive association may have been a chance finding. © The Author 2013

Birth size in the most recent pregnancy and maternal mortality in premenopausal breast cancer by tumor characteristics

The main aim of this study was to investigate possible associations between measures of offspring size at birth in the most recent pregnancy before premenopausal breast cancer diagnosis and the risks of maternal breast cancer mortality, taking tumor characteristics into account. We also aimed to investigate if these associations are modified by age at childbirth, time since childbirth, parity, and age at diagnosis. We followed 6,019 women from their date of premenopausal breast cancer (diagnosed from 1992 to 2008) until emigration, death or December 31st, 2009, whichever occurred first. We used Cox proportional hazard regression models, adjusted for parity, age at diagnosis, and education level, to estimate associations between women pregnancy, cancer characteristics and offspring birth characteristics, and mothers' mortality risk. In stratified analyses, mortality risks were estimated by tumor stage, ER or PR status. There was no association between offspring birth weight (HR = 1.00, 95 % CI 0.99-1.01, when used as a continuous variable), birth weight for gestational age or ponderal index, and premenopausal breast cancer mortality. Similarly, in analyses stratified by tumor stage, receptor status, and time difference between last pregnancy and date of diagnosis, we found no associations between birth size and breast cancer mortality. Our findings suggest that the hypothesis that "premenopausal breast cancer mortality is associated with offspring birth characteristics in the most recent pregnancy before the diagnosis" may not be valid. In addition, these associations are not modified by tumor characteristics. © 2014 Springer Science+Business Media New York

Scholastic achievement at age 16 and risk of schizophrenia and other psychoses: a national cohort study

Background: There is abundant evidence that schizophrenia is associated with cognitive deficits in childhood. However, previous studies investigating school performance have been inconclusive. Furthermore, there are several biological and social factors that could confound the association. We investigated whether school performance at age 16 is associated with risk of adult schizophrenia and other psychoses in a large national cohort, while controlling for multiple confounders. Method: Using a national sample of 907 011 individuals born in Sweden between 1973 and 1983, we used Cox regression to assess whether scholastic achievement at age 15-16 predicted hospital admission for psychosis between ages 17 and 31, adjusting for potential confounders. Results: Poor school performance was associated with increased rates of schizophrenia [hazard ratio (HR) 3.9, 95% confidence interval (CI) 2.8-5.3], schizo-affective disorder (HR 4.2, 95% CI 1.9-9.1) and other psychoses (HR 3.0, 95% CI 2.3-4.0). Receiving the lowest (E) grade was significantly associated with risk for schizophrenia and other psychoses in every school subject. There was no evidence of confounding by migrant status, low birthweight, hypoxia, parental education level or socio-economic group. Conclusions: Poor school performance across all domains is strongly associated with risk for schizophrenia and other psychoses. Copyright © 2007 Cambridge University Press.link_to_subscribed_fulltex

Maternal age, education level and migration: Socioeconomic determinants for smoking during pregnancy in a field study from Turkey

WOS: 000279909900003PubMed ID: 20534133Background: Smoking during pregnancy has been associated with socioeconomic determinants and it is recognized as the most important preventable risk factor for an unsuccessful pregnancy outcome. Turkey has national data on the prevalance of smoking during pregnancy; however there is no data on the characteristics of the high-risk population. This is a field study that aims to identify socioeconomic determinants for smoking during pregnancy as well as differentiating the daily and occasional smokers. Method: Cross sectional study was conducted among women with 0-5 year old children living in the area served by Primary Health Care Center (PHCC) in Burhaniye, Turkey. Face-to-face interviews were conducted by the researchers during January-March 2008 at the home of the participants with 83.7% response rate (n = 256). The relation of "smoking during pregnacy" and "daily smoking during pregnancy" with the independent variables was determined with chi(2) tests. Women's age, educational level, number of previous births, place of origin, migration, partner's educational level, poverty, perceived income, social class were evaluated. Statistical significance was achieved when the p value was less than 0.05. The variables in relation with the dependent variables in the chi(2) tests were included in the forward-stepwise logistic analysis. Results: Prevalance of smoking during pregnancy was 22.7%. The majority (74.1%) were daily smokers. Young mothers (< 20), low educated women and migrants were at increased risk for smoking during pregnancy. Low education and being a migrant were risk factors for daily consumption (p < 0.05). Conclusions: Systematic attention should be paid to socioeconomic determinants in smoking for pregnant women, especially in countries like Turkey with high rates of infant and mother mortality and substantial health inequalities. Young mothers (< 20), low educated women and migrants are important groups to focus on