This longitudinal study investigated neurobehavioral development in the human fetus from 24 to 36 weeks gestation. Subject (N=103) were stratified by socioeconomic class. Fetal data were collected for 50 min at three intervals, and included measures of heart rate, movement, and biobehavioral patterns. Repeated measures analysis of variance by fetal sex and maternal socioeconomic status was used...

BACKGROUND The expected ratio of male to female births is generally believed to be 1.05, also described as the male proportion of 0.515. OBJECTIVES We describe trends in sex ratio at birth and in fetal deaths in the United States, in African Americans and in whites, and in Japan, two industrial countries with well-characterized health data infrastructures, and we speculate about possible expl...

The troubling practice of fetal sex selection has historically been considered an Asian phenomenon. However, recent evidence shows that a similar situation is emerging in North America, albeit on a smaller scale. The Society of Obstetricians and Gynaecologists of Canada has firmly stated its opposition to sex selection for non-medical reasons, as well as to the use of any technology used solely...

context prenatal testing aims to identify fetal chromosomal and genetic disorders prior to delivery. current invasive procedures such as amniocentesis and chorionic villus sampling (cvs) pose a risk to mother and fetus and such diagnostic procedures are available only to high-risk pregnancies, which limits aneuploidy detection rate. the identification of cell-free fetal dna (cffdna) in maternal ...

This paper presents results of a study designed to: 1) test for a sex difference in the relative lengths of the finger bones, including the second-to-fourth digit ratio (2D:4D), using left-hand radiographs taken in young children, 2) test whether sex differences can be explained by sex differences in fetal growth, and 3) test the serial stability of sex differences in relative digit lengths, in...