Pregnancy

About: Pregnancy is a research topic. Over the lifetime, 163969 publications have been published within this topic receiving 4013502 citations. The topic is also known as: pregnancy & gestation.

Reduced fetal growth rate and increased risk of death from ischaemic heart disease: cohort study of 15 000 Swedish men and women born 1915-29

Abstract: Objective: To establish whether fetal growth rate (as distinct from size at birth) is associated with mortality from ischaemic heart disease. Design: Cohort study based on uniquely detailed obstetric records with 97% follow up over the entire life course and linkage to census data in adult life. Subjects: All 14 611 babies delivered at the Uppsala Academic Hospital, Sweden, during 1915-29 followed up to end of 1995. Main outcome measures: Mortality from ischaemic heart disease and other causes. Results: Cardiovascular disease showed an inverse association with birth weight for both men and women, although this was significant only for men. In men a 1000 g increase in birth weight was associated with a proportional reduction in the rate of ischaemic heart disease of 0.77 (95% confidence interval 0.67 to 0.90). Adjustment for socioeconomic circumstances at birth and in adult life led to slight attenuation of this effect. Relative to the lowest fourth of birth weight for gestational age, mortality from ischaemic heart disease in men in the second, third, and fourth fourths was 0.81 (0.66 to 0.98), 0.63 (0.50 to 0.78), and 0.67 (0.54 to 0.82), respectively. The inclusion of birth weight per se and birth weight for gestational age in the same model strengthened the association with birth weight for gestational age but removed the association with birth weight. Conclusions: This study provides by far the most persuasive evidence of a real association between size at birth and mortality from ischaemic heart disease in men, which cannot be explained by methodological artefact or socioeconomic confounding. It strongly suggests that it is variation in fetal growth rate rather than size at birth that is aetiologically important.

Epidemiology of preterm birth

Abstract: Preterm birth is a major challenge in perinatal health care. Most perinatal deaths occur in preterm infants, and preterm birth is an important risk factor for neurological impairment and disability. Preterm birth not only affects infants and their families—providing care for preterm infants, who may spend several months in hospital, has increasing cost implications for health services. Preterm birth is the delivery of a baby before 37 completed weeks' gestation. Most mortality and morbidity affects “very preterm” infants (those born before 32 weeks' gestation), and especially “extremely preterm” infants (those born before 28 weeks of gestation). Definitions of preterm live births by completed weeks of gestation Over the past 20-30 years advances in perinatal care have improved outcomes for infants born after short gestations. The number of weeks of completed gestation that defines whether a birth is preterm rather than a fetal loss has become smaller. In 1992 the boundary that required registration as a preterm live birth in the United Kingdom was lowered from 28 completed weeks' gestation to 24 weeks' gestation. This boundary varies internationally, however, from about 20 to 24 weeks. Some classification of fetal loss, still birth, and early neonatal death for these very short gestations may be unreliable. Even in developed countries, there is often uncertainty and incomplete recording of estimates of gestation. In most of the United Kingdom data on birth weight data but not on gestational age are collected routinely. Although some concordance exists between the categories of birth weight and gestational age, they are not interchangeable. The categories for birth weight are: Only around two thirds of …

Prenatal glucocorticoids and long-term programming.

Abstract: Epidemiological evidence suggests that low birth weight is associated with an increased risk of cardiovascular, metabolic and neuroendocrine disorders in adult life. Glucocorticoid administration during pregnancy reduces offspring birth weight and alters the maturation of the lung and other organs. We hypothesised that prenatal exposure to excess glucocorticoids or stress might represent a mechanism linking foetal growth with adult pathophysiology. In rats, birth weight is reduced following prenatal exposure to the synthetic steroid dexamethasone, which readily crosses the placenta, or to carbenoxolone, which inhibits 11b-hydroxysteroid dehydrogenase type 2 (11b-HSD2), the physiological fetoplacental ‘barrier’ to maternal glucocorticoids. As adults, the offspring exhibit permanent hypertension, hyperglycaemic, increased hypothalamic-pituitary-adrenal (HPA) axis activity and behaviour reminiscent of anxiety. Physiological variations in placental 11b-HSD2 activity correlate directly with foetal weight. In humans, 11b-HSD2 gene mutations cause low birth weight. Moreover, lowbirth-weight babies have higher plasma cortisol levels throughout adult life, indicating HPA axis programming. The molecular mechanisms may reflect permanent changes in the expression of specific transcription factors, key among which is the glucocorticoid receptor (GR) itself. The differential programming of the GR in different tissues reflects effects upon one or more of the multiple tissue-specific alternate first exons/promoters of the GR gene. Overall, the data suggest that both pharmacological and physiological exposure prenatally to excess glucocorticoids programmes cardiovascular, metabolic and neuroendocrine disorders in adult life. European Journal of Endocrinology 151 U49–U62

Physiological changes in pregnancy.

Abstract: Physiological changes occur in pregnancy to nurture the developing foetus and prepare the mother for labour and delivery. Some of these changes influence normal biochemical values while others may mimic symptoms of medical disease. It is important to differentiate between normal physiological changes and disease pathology. This review highlights the important changes that take place during normal pregnancy.