OBJECTIVES To test the contraceptive confidence hypothesis in a modern context. The hypothesis is that women using effective or modern contraceptive methods have increased contraceptive confidence and hence a shorter interval between marriage and first birth than users of ineffective or traditional methods. We extend the hypothesis to incorporate the role of abortion, arguing that it acts as a ...

BACKGROUND Studies have found associations between low birth weight and increased risks of cardiovascular diseases in adulthood. However, these associations could be due to confounding by genetic or socioeconomic factors. METHODS AND RESULTS We performed a study on Swedish like-sexed twins with known zygosity who were born from 1926 to 1958. First, to obtain an overall effect of birth weight ...

BACKGROUND Mothers of multiples are alleged to be more fecund than mothers of singletons. Some authors have suggested monitoring twinning rates for assessing temporal changes in a population's reproductive health. METHODS Using a nested case-control design, we estimated the odds of a multiple birth in relation to fecundity in the US Collaborative Perinatal Project inclusive of 8546 pregnant w...

Associations between low birth weight (≤2,500 g) and increased risk of mortality and morbidity provided the foundation for the "developmental origins of health and disease" hypothesis. Previous between-family studies could not control for unmeasured confounders. Therefore, we compared differentially exposed siblings to estimate the extent to which the associations were due to uncontrolled facto...

Dynamic panel data model of infant deaths, birth spacing and contraception are estimated incorporating causal effects of birth spacing on subsequent mortality and of mortality on the use of contraceptives and the length of next birth interval. Data come from the renowned demographic field Health and Demographic Surveillance System in the icddr,b treatment area in Matlab, Bangladesh, on 31,968 c...

BACKGROUND Birth order has been proposed as a cardiovascular risk factor, because the lower birth weight and greater infant weight gain typical of firstborns could programme metabolism detrimentally. METHODS We examined the associations of birth order (firstborn or laterborn) with birth weight-for-gestational age, length/height and body mass index (BMI) z-scores during infancy, childhood, and...