Hyperemesis gravidarum and subsequent breast cancer risk

Both parity and a young age at first pregnancy are associated with a reduction in breast cancer risk. The hormones involved in this process are not fully investigated. Human chorionic gonadotropin is a placental hormone, which in rats and in human breast cells in vitro has been shown to prevent against breast cancer. Hyperemesis, a severe nausea combined with vomiting during pregnancy, is associated with increased levels of human chorionic gonadotropin. We investigated the possible relationship between hyperemesis and subsequent breast cancer risk in a case–control study based on registry data. Among 13 079 breast cancer cases and 34 348 individually matched controls we found 148 cases and 405 controls who had been hospitalised for hyperemesis. Hyperemesis was not associated with breast cancer risk (adjusted odds ratio 1.05, 95% confidence interval 0.86–1.27), and similar risks were observed regardless of age at diagnosis, number of hospitalisations for hyperemesis or time of follow-up. Our results do not support the hypothesis that human chorionic gonadotropin is responsible for the protective effect of pregnancies upon breast cancer risk

Effect of Body Mass Index on pregnancy outcomes in nulliparous women delivering singleton babies

Peer reviewedPublisher PD

Estimation of optimal birth weights and gestational ages for twin births in Japan

BACKGROUND: As multiple pregnancies show a higher incidence of complications than singletons and carry a higher perinatal risk, the calculation of birth weight – and gestational age (GA)-specific perinatal mortality rates (PMR) for multiple births is necessary in order to estimate the lowest PMR for these groups. METHODS: Details of all reported twins (192,987 live births, 5,539 stillbirths and 1,830 early neonatal deaths) in Japan between 1990 and 1999 were analyzed and compared with singletons (10,021,275 live births, 63,972 fetal deaths and 16,862 early neonatal deaths) in the annual report of vital statistics of Japan. The fetal death rate (FDR) and PMR were calculated for each category of birth weight at 500-gram intervals and GA at four-week intervals. The FDR according to birth weight and GA category was calculated as fetal deaths/(fetal deaths + live births) × 1000. The perinatal mortality rate (PMR) according to birth weight and GA category, was calculated as (fetal deaths + early neonatal deaths)/(fetal deaths + live births) × 1000. Within each category, the lowest FDR and PMR were assigned with a relative risk (RR) of 1.0 as a reference and all other rates within each category were compared to this lowest rate. RESULTS: The overall PMR per 1,000 births for singletons was 6.9, and the lowest PMR was 1.1 for birth weight (3.5–4.0 kg) and GA (40- weeks). For twins, the overall PMR per 1,000 births was 36.8, and the lowest PMR was 3.9 for birth weight (2.5–3.0 kg) and GA (36–39 weeks). At optimal birth weight and GA, the PMR was reduced to 15.9 percent for singletons, and 10.6 percent for twins, compared to the overall PMR. The risk of perinatal mortality was greater in twins than in singletons at the same deviation from the ideal category of each plurality. CONCLUSION: PMRs are potentially reduced by attaining the ideal birth weight and GA. More than 90 percent of mortality could be reduced by attaining the optimal GA and birth weight in twins by taking particular care to ensure appropriate pregnancy weight gain, as well as adequate control for obstetric complications

Prenatal X-ray exposure and childhood brain tumours: a population-based case–control study on tumour subtypes

We investigated childhood brain tumours by histological subtype in relation to prenatal X-ray among all children, less than 15 years of age, born in Sweden between 1975 and 1984. For each case, one control was randomly selected from the Medical Birth Register, and exposure data on prenatal X-ray were extracted blindly from antenatal medical records. Additional information on maternal reproductive history was obtained from the Medical Birth Register. We found no overall increased risk for childhood brain tumour after prenatal abdominal X-ray exposure (adjusted odds ratio (OR): 1.02, 95% confidence interval (CI): 0.64–1.62); primitive neuroectodermal tumours had the highest risk estimate (OR: 1.88, 95% CI: 0.92–3.83)

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

Continuous growth reference from 24th week of gestation to 24 months by gender

<p>Abstract</p> <p>Background</p> <p>Growth charts and child growth assessment have become prime global instruments in child health practice over the 30 years. An updated, continuous growth standard that bridges size at birth values with postnatal growth values can improve child growth screening and monitoring.</p> <p>Methods</p> <p>This novel growth chart was constructed from two sources of information. Size at birth (weight, length and head circumference) reference values were updated based on information of normal deliveries (i.e. singleton live births without severe congenital malformation, with healthy mothers and born vaginally) from the Swedish Medical Birth Registry, 1990–1999 (n = 810393). Weight was evaluated using logarithmic transformation as for postnatal weight. Standard deviations were estimated from data within the empirical mean ± 1.0 SD for each gestational week and gender. These values were smoothed by empirical curve-fitting together with values from our recently published postnatal growth reference including 3650 longitudinally followed children from birth to final height <abbrgrp><abbr bid="B9">9</abbr></abbrgrp>. Timescale and weight axes were made logarithmic in order to magnify the early time part of the graph.</p> <p>Results</p> <p>This study presents the first continuous gender specific growth chart from birth irrespective of gestational age at birth until 2 years of age for weight, length and head circumference. Birth weight at 40 weeks of gestation increased approximately 100 gram and length increased only 1 mm compared with earlier Swedish reference from 1977–81. The curve is now less S-shaped as compared with earlier curves and compared with 4 curves from other countries and with more constant variation over the whole range.</p> <p>Conclusion</p> <p>Our values picture the unrestricted pattern of growth improving the detection of a deviating growth pattern, when the growth of an individual infant is plotted on the charts. Especially for very preterm infants age corrected growth can be more easily evaluated although it must be recognized that the early comparison is with what is estimated as normal growth in uterus. The reference values are useful in child health care systems for population screening, but also in research or in the clinic for evaluating various growth promoting interventions – either nutritional, surgical or therapeutic – that might affect a child in early life.</p

Evidence of space–time clustering of childhood acute lymphoblastic leukaemia in Sweden

We have examined 645 recorded cases of childhood acute lymphatic leukaemia (ALL) in Sweden during 1973–89 to identify space–time clustering by using the close-pair method of Knox. The records included date of birth and of diagnosis as well as addresses at birth and at diagnosis. There was a significant excess of case pairs close in date of birth and place of birth in the 5- to 15-year age group. © 1999 Cancer Research Campaig

Factors associated with smoking in pregnancy

The aim of this cross-sectional study was to identify factors related to smoking during pregnancy. The sample included 267 puerperae hospitalized in the maternity unit of a university hospital in Porto Alegre/RS. The data were collected through a self-applied instrument and statistically analyzed. The majority of the puerperae (51.3%) were between 18 and 25 years old, 55.4% were nonsmokers, 25.5% were smokers, 19.1% had recently ceased smoking (in abstinence). The nonsmokers had more consultations than the smokers and the abstinent smokers (p=0.025). The number of women who had more than one child was higher among smokers than among nonsmokers and abstinent smokers (p=0.002). Women were more likely to stop smoking before pregnancy when they had a partner who was a nonsmoker (p=0.007). Several factors influence smoking and smoking cessation and these are important in prenatal interventions aimed at pregnant women and their partners

Population-based trends in pregnancy hypertension and pre-eclampsia: an international comparative study

Objective: The objective of this study was to compare international trends in pre-eclampsia rates and in overall pregnancy hypertension rates (including gestational hypertension, pre-eclampsia and eclampsia). Design: Population data (from birth and/or hospital records) on all women giving birth were available from Australia (two states), Canada (Alberta), Denmark, Norway, Scotland, Sweden and the USA (Massachusetts) for a minimum of 6 years from 1997 to 2007. All countries used the 10th revision of the International Classification of Diseases, except Massachusetts which used the 9th revision. There were no major changes to the diagnostic criteria or methods of data collection in any country during the study period. Population characteristics as well as rates of pregnancy hypertension and pre-eclampsia were compared. Results: Absolute rates varied across the populations as follows: pregnancy hypertension (3.6% to 9.1%), pre-eclampsia (1.4% to 4.0%) and early-onset preeclampsia (0.3% to 0.7%). Pregnancy hypertension and/or pre-eclampsia rates declined over time in most populations. This was unexpected given that factors associated with pregnancy hypertension such as prepregnancy obesity and maternal age are generally increasing. However, there was also a downward shift in gestational age with fewer pregnancies reaching 40 weeks. Conclusion: The rate of pregnancy hypertension and pre-eclampsia decreased in northern Europe and Australia from 1997 to 2007, but increased in Massachusetts. The use of a different International Classification of Diseases coding version in Massachusetts may contribute to the difference in trend. Elective delivery prior to the due date is the most likely explanation for the decrease observed in Europe and Australia. Also, the use of interventions that reduce the risk of pregnancy hypertension and/or progression to pre-eclampsia (low-dose aspirin, calcium supplementation and early delivery for mild hypertension) may have contributed to the decline

Predictive factors of developing diabetes mellitus in women with gestational diabetes.

BACKGROUND: To investigate which factors during gestational diabetes pregnancies correlate with the risk of developing impaired glucose tolerance or diabetes 1 year postpartum and to compare this risk in women with gestational diabetes and women with a normal oral glucose tolerance test during pregnancy. METHODS: Of 315 women with gestational diabetes, defined as a 2-hr blood glucose value of at least 9.0 mmol/l at a 75-g oral glucose tolerance test, who delivered in Lund 1991-99, 229 (73%) performed a new test 1 year postpartum. We compared maternal and fetal factors during pregnancy with the test value at follow up. A control group of 153 women with a 2-hr test value below 7.8 mmol/l during pregnancy were invited to a new test 1 year postpartum and 60 (39%) accepted. RESULTS: At 1 year follow up, 31% of the women with gestational diabetes but only one of the 60 controls showed pathologic glucose tolerance and one had developed diabetes. The following factors in women with gestational diabetes were identified as predicting impaired glucose tolerance or diabetes at 1 year follow up: maternal age over 40 and--in a multiple regression analysis, independent of each other--a high 2-hr value at oral glucose tolerance test during pregnancy and insulin treatment during pregnancy. CONCLUSION: The risk of developing manifest diabetes after gestational diabetes may be high enough to justify a general screening or diagnostic procedure in all pregnant women to identify women with gestational diabetes and a postpartum follow up program for them. This study did not identify any particular factor during pregnancy with enough precision to predict a later progression to diabetes