Objective: To assesses chromosomal aberrations in the abortus in recurrent miscarriage, in the presence of parental chromosomal aberrations.
Design: Retrospective comparative cohort study.
Setting: Tertiary referral unit in university hospital.
Patient(s): One thousand one hundred eight patients with 3-16 miscarriages before 20 weeks gestation; 113 patients with and 995 without chromosomal aberrations.
Intervention(s): Karyotyping by standard G-banding techniques of both parents, and of 205 abortuses collected at curettage.
Main outcome measure(s): The incidence of the euploidic and aneuploidic abortuses according to the parental karyotype.
Result(s): Two hundred three abortuses were successfully karyotyped. In 164 embryos of patients with no parental chromosomal aberrations, 23.2% (38/164) had chromosome aberrations. Of the 39 abortuses karyotyped in patients with chromosomal aberrations, 17 had normal karyotypes, 8 had balanced translocations, 2 had inversions identical to the parents, and 12 (30.8%) had abnormal karyotypes. This difference is not statistically significant (odd ratio 1.47, 95% confidence interval 0.63-3.39). Only 4 of the 39 karyotyped abortuses had an unbalanced translocation.
Conclusion(s): Parental karyotyping was not particularly predictive of a subsequent miscarriage as a result of chromosomal aberrations as 43.5% of abortuses were euploidic, and the parental aberration was only passed on to the abortus in 10% of cases.