Chromosomal miscarriage and pregnancy outcomes in recurrent pregnancy loss

Abstract: This prospective cohort study aimed to assess whether a history of embryonic chromosomal abnormality affects subsequent pregnancy outcomes in women with unexplained recurrent pregnancy loss. A total of 233 women with unexplained recurrent pregnancy loss who conceived naturally were included. Participants were categorized according to the chromosomal status of prior miscarriages. A multivariate logistic regression model was constructed to predict live birth based on these categories and observed pregnancy outcomes. Among the 233 included women, 171 (73.4%) had a live birth, while 62 (26.6%) experienced early pregnancy loss. Among women with one abnormal chromosomal miscarriage (n = 110), 94 (85.5%) had a live birth, accounting for 40.3% of the total cohort. In contrast, in the one normal chromosomal miscarriage group (n = 77), 47 (61.0%) achieved live birth, representing 20.2% of the total. The model identified a history of one chromosomally abnormal miscarriage (odds ratio = 3.88, 95% confidence interval: 1.87-8.06) and history of two chromosomally abnormal miscarriages (odds ratio = 8.93, 95% confidence interval: 1.07-74.55) as significant predictors of live birth. The predictive model achieved an area under the curve of 0.73 in the training dataset and 0.75 in the testing dataset. A history of embryonic chromosomal miscarriage may reflect improved pregnancy prospects and inform clinical counseling in unexplained recurrent pregnancy loss. Lay summary: Women with unexplained recurrent miscarriage often wonder whether their history will affect future natural pregnancies. Chromosomal abnormalities in embryos are a leading cause of miscarriage, but the impact of such a history on later outcomes has remained unclear. We studied 233 women with repeated unexplained losses and assessed their subsequent pregnancy results. Overall, 73.4% achieved a live birth, while 26.6% had another early miscarriage. Interestingly, among women who had one chromosomal abnormal miscarriage, 85.5% subsequently achieved a live birth. In contrast, the live birth rate was lower in the group who had a normal chromosomal miscarriage; only 61.0% went on to achieve a live birth. These results suggest that a history of abnormal chromosomal miscarriage may indicate better chances of future pregnancy and help guide clinical care.