Objective: About 15% of clinically recognized pregnancies result in spontaneous abortion in the first trimester and the vast majority of these are the result of chromosome abnormalities. Studies of chromosomal constitutions of first trimester spontaneous abortions have revealed that at least 50% of the abortions have an abnormal karyotype. In this study we aimed to report the single centre experience of anomalies detected in spontaneous abortions.

Material and Method: We present rare numerical and structural cytogenetic abnormalities detected in spontaneous abortion materials and the histopathological findings of rest material of abortion specimens in our study population.

Results: Among 457 cases, 382 were successfully karyotyped while cell culture of 75 cases failed. Cytogenetic abnormalities were detected in 127 of 382 cases (33.24%). Autosomal trisomies were the predominant chromosomal abnormalities with a frequency of 48.8%. Structural chromosomal abnormalities were infrequent in conception materials. The mean age of the mothers was highest in trisomy group, the difference being significantly important (ANOVA p< 0.001). The most frequent chromosomal abnormalities were Turner syndrome, triploidy and trisomy of chromosome 16 followed by trisomy of chromosomes 22 and 21 and tetraploidy. Double trisomies and structural chromosomal abnormalities were rare. Trisomies were more frequent in advanced maternal age.

Conclusion: Detection of chromosomal abnormalities in spontaneous abortion materials is very important to clarify the causes of loss of pregnancy. Detection of structural chromosomal abnormalities in the cases and their carrier parents can provide proper genetic counseling to these families. These families can be directed towards pre-implantation genetic diagnosis to prevent further pregnancies with complications.