Euploid sporadic miscarriage in advanced-age women is associated with reduced live birth rates in subsequent pregnancies

Euploid miscarriage may indicate underlying non-genetic factors in the couples. This study aimed to investigate the subsequent live birth rates in women with a prior euploid or aneuploid sporadic miscarriage (SM) in assisted reproductive technology (ART). This retrospective study included 1,186 eligible women with a prior cytogenetically confirmed SM who underwent subsequent blastocyst transfer cycles. The pregnancy outcomes were compared by maternal age and the ploidy of the previous miscarriage. In women aged < 35 years, the subsequent live birth rate (LBR) was comparable between euploid and aneuploid SM groups (55.2% vs. 60.2%; P = 0.194). However, among women aged 35–37 years, the LBR was significantly lower in those with a previous euploid SM than in those with a history of aneuploid SM (38.2% vs. 52.6%; P = 0.038). Among women ≥ 38 years, the euploid SM group also demonstrated a lower LBR (26.7% vs. 39.8%; P = 0.072). After adjusting for confounders, prior aneuploid SM was associated with significantly higher odds of live birth in the 35–37 years group (aOR 1.861; 95% CI 1.030–3.361; P = 0.040), and a similar trend was observed in the ≥ 38 years group (aOR 2.251; 95% CI 0.977–5.190; P = 0.057). A single euploid SM might be associated with reduced live birth rate in their subsequent pregnancies for women aged ≥ 35 years. However, the pregnancy outcomes were comparable in women aged <35 years, regardless of the karyotype of products of conception.