Normal and abnormal reproductive behavior of dogs and cats, and known and proposed hormonal bases for these behaviors are addressed. Emerging information includes use of oxytocin to promote pair-bonding between dam and offspring and the possible effect of prolactin in inhibiting sexual behaviors.

THIS PAPER BRINGS A SYNTHESIS OF SOME OF THE MAIN RESULTS PROVIDED BY GRAVAD SURVEY (TEENAGE PREGNANCY: multicentric study about youth, sexuality and reproduction in Brazil). GRAVAD is a study about sexual and reproductive behavior among Brazilian youth that interviewed 4,634 individuals in a population survey with a random sample. Women and men between 18 and 24 years old were interviewed in t...

INTRODUCTION Communication between parents and adolescents regarding sexuality is an important reproductive health topic. Due to complexities associated with adolescent's physiological development, sexuality should be dealt with holistically. This study aimed to investigate factors affecting effective communication between parents and adolescents concerning sexual and reproductive health issues...

CONTEXT Women's employment opportunities may reduce the risk of early intercourse and pregnancy, but some evidence has linked adolescent employment and problem behaviors with early intercourse. METHODS Hazard regression analyses of data from the National Longitudinal Survey of Youth were used to examine the relationship between employment and the risk of first intercourse before age 20 among ...

Recent research indicating that roughly a third of the variation in female orgasmic frequency is heritable leaves a substantial amount of non-heritable variation to be explained. Given that emotion regulation is central to attachment theory and that attachment insecurity in infancy and avoidance in adulthood are not heritable, it was predicted that (higher levels of) avoidance would predict (lo...

The reproductive behaviour of the sexually coercive male eastern mosquitofish (Gambusia holbrooki) offers an excellent model system for testing the benefits of reversible thermal acclimation responses to mating success. We acclimated male mosquitofish to either 18 or 30 degrees C (14 h light:10 h dark) for six weeks and tested their ability to obtain coercive copulations in the presence and the...

This study in Egypt, measured the son preference index, its determinants, and impact on reproductive behaviour and intention of 400 mothers attending for delivery. Overall son preference index was 1.4. The causes of sex preference were mainly psychological and social. Mothers with only girls were 496 times more likely to prefer a son as compared to those with boys only. Mothers with illiterate ...

Human reproductive behaviour is marked by exceptional variation at the population and individual level. Human behavioural ecologists propose adaptive hypotheses to explain this variation as shifting phenotypic optima in relation to local socioecological niches. Here we review evidence that variation in fertility (offspring number), in both traditional and modern industrialized populations, repr...

We use data from the Demographic and Health Surveys to examine the patterns of stall in fertility decline in four Eastern African countries. Contrary to patterns of fertility transition in Africa that cut across various socio-economic and geographical groups within countries, we find strong selectivity of fertility stall across different groups and regions in all four countries. In both Kenya a...