Maternal serum leptin concentration during the second trimester of pregnancy: association with fetal chromosomal abnormalities.

Recent studies suggest that leptin, the product of the obese gene, is produced by the placenta during pregnancy. The present study addressed the question whether second trimester maternal serum leptin could be altered by fetal Down syndrome or Edwards syndrome. Maternal serum leptin concentrations were measured in 18 pregnancies complicated with Down syndrome, six pregnancies complicated with Edwards syndrome and 183 uncomplicated pregnancies during the second trimester of pregnancy.

Cytogenetics of recurrent abortions.

G-banded chromosome complements were analysed from both partners of 150 couples who had had two or more spontaneous abortions. Two women and four men were found to be balanced translocation carriers, as follows: 46,XX,t(2;10), 46,XX,t(6;11), 46,XY,t(6;10), 45,XY,t(13;14), 45,XY,t(13;14), 45,XY,t(14;21). Another woman had an abnormal karotype 46,XX/47,XXX and a man had a pericentric inversion of chromosome 1; six other men and two women had pericentric inversions of chromosome 9.

The transition in frequency of Y-chromatin in males during early infancy.

The frequency of Y-positive lymphocytes in blood smears at delivery and during early infancy was assessed to determine the exact time at which it is similar to the frequency in adults. It was found that at day 0 of life the frequency of Y-chromatin-positive cells was 26.6 +/- 13.