N. Rojansky

IVF-ET provides unique controlled conditions for the study of seasonal influences on the human reproductive process. This study was designed to evaluate the effects of seasonality on fertilization rate, embryo quality, and conception rates. A retrospective observational cohort study. A chart review of all individuals undergoing IVF-ET from 1988 to 1991 at our institution was performed. An assisted reproduction unit at a university-based tertiary medical center. 657 women, for a total of 1074 IVF-ET treatment cycles, were evaluated. From this population, we chose 305 women undergoing their first IVF-ET cycle for reasons of pure mechanical infertility. IVF-ET cycles. Seasonal variability in fertilization rates and quality-A embryo rates, and the correlation with the absolute number of light hours, as well as the influence of temperature, humidity, and other environmental parameters. A significant seasonal variability in the fertilization rate and the quality-A embryo rate was demonstr...

Osteoporosis has become a major public health problem in many western countries in which about 25% of women by the age of 65 will have had osteopenic fractures. The most important contributing factor to this condition is loss of gonadal function. This progressive disease, characterized by reduction in bone mass, may be prevented by estrogen replacement therapy. While there are several methods of diagnosing the disease when already established, there is no method that can identify women at high risk of developing osteoporosis. We have developed a biological test in which the serum of postmenopausal women is added to rat osteoprogenitor cell culture and its influence on proliferation, differentiation and mineralization of bone cells is determined. The serum of 20 menopausal women was examined by the biological test and the results compared to the findings of dual photon absorptiometry. This showed that rapid bone-losers had a significantly lower mineralization index as compared to non...

An Rh-negative woman with preexisting anti-D antibodies may affect some or all subsequent fetuses, depending on the genotype of her Rh-positive partner. Currently, a reliable technique for an absolute determination of RhD genotype is not available. This study was initiated to develop an accurate method for RhD genotyping in men. RhD genotype was determined by deoxyribonucleic acid amplification of a D-specific sequence in single sperm cell samples. Micromanipulation techniques were used for sampling of single sperm cells, which were further amplified by multiplex nested polymerase chain reaction at the RhD locus. A RhD sequence amplification product was expected in all of the successfully amplified samples from Rh-positive homozygotes, in some of the samples from heterozygotes, and in none of the samples form Rh-negative subjects. RhD genotype was accurately determined in 10 of 10 donors. A total of 132 single sperm cells were analyzed (8 to 17 samples per donor), of which 96 were s...