OBJECTIVE: To study the role of chromosomal aberration in the causation of recurrent spontaneous abortion (RSA) in Chinese population. METHODS: A total of 514 Chinese couples with 2 or more spontaneous abortions at less than 24 weeks of gestation were included. For each proband, a minimum of 13 metaphases were analyzed by G-banding. Additional cells (usually 50-100 cells) were screened when mosaicism was suspected. Chi 2 test was used to compare the number and frequency of couples with and without balanced translocation with respect to whether liveborn was present or absent. Chi 2 test for trend was used to show whether a correlation existed between the occurrence of balanced translocation and the number of spontaneous abortions at ascertainment. RESULTS: The overall incidence of chromosome anomaly was 51 out of 514 (9.92%). Chi 2 test for trend analysis showed that the chance of one member of a couple being a balanced carrier increased with the number of spontaneous abortions. The chance of finding translocation in couples with liveborn was higher than that in couples without liveborn, but the difference was not statistically significant. We also found that pericentric inversion 9 did not play an important role in the causation of recurrent abortion. CONCLUSIONS: Cytogenetic analysis is indicated in couples with 2 or more spontaneous abortions and the chance of finding chromosomal aberration increases with the number of abortions at the time of ascertainment.
OBJECTIVE: To study the role of chromosomal aberration in the causation of recurrent spontaneous abortion (RSA) in Chinese population. METHODS: A total of 514 Chinese couples with 2 or more spontaneous abortions at less than 24 weeks of gestation were included. For each proband, a minimum of 13 metaphases were analyzed by G-banding. Additional cells (usually 50-100 cells) were screened when mosaicism was suspected. Chi 2 test was used to compare the number and frequency of couples with and without balanced translocation with respect to whether liveborn was present or absent. Chi 2 test for trend was used to show whether a correlation existed between the occurrence of balanced translocation and the number of spontaneous abortions at ascertainment. RESULTS: The overall incidence of chromosome anomaly was 51 out of 514 (9.92%). Chi 2 test for trend analysis showed that the chance of one member of a couple being a balanced carrier increased with the number of spontaneous abortions. The chance of finding translocation in couples with liveborn was higher than that in couples without liveborn, but the difference was not statistically significant. We also found that pericentric inversion 9 did not play an important role in the causation of recurrent abortion. CONCLUSIONS: Cytogenetic analysis is indicated in couples with 2 or more spontaneous abortions and the chance of finding chromosomal aberration increases with the number of abortions at the time of ascertainment.