Novel Insights into Normal Karyotype Miscarriage: Distinctive Patterns and Implications for Diagnosis Based on Next-Generation Sequencing Analysis.

PURPOSE: This study aimed to identify the clinical differences between normal and abnormal karyotype miscarriages and evaluate whether clinical findings could predict the presence or absence of chromosomal abnormalities.

METHODS

A total of 117 patients with early miscarriage who underwent chorionic villus chromosomal testing using next-generation sequencing were retrospectively analyzed. Clinical findings were compared between the normal (euploid; n = 47) and abnormal karyotype (aneuploid; n = 70) groups.

RESULTS

Normal karyotype miscarriages occurred significantly more often before yolk sac visualization (29.8% vs. 0%, p < 0.0001) and before fetal heartbeat confirmation (51.1% vs. 15.7%, p = 0.0001) than abnormal karyotype miscarriages. The mean crown-rump length was larger in the normal karyotype group (15.3 ± 8.2 mm vs. 11.8 ± 6.8 mm, p = 0.037). Normal karyotype miscarriages exhibited a bimodal distribution in gestational age at miscarriage. In addition, the normal karyotype was associated with a history of two or more biochemical pregnancy losses (21.3% vs. 7.1%, p = 0.045).

CONCLUSION

Distinct clinical and ultrasonographic patterns were observed in normal and abnormal karyotype miscarriages. These features have limited diagnostic value, and their usefulness in supporting counseling or decision-making is also limited when genetic testing is not available.