Objective: To identify the influence of parental abnormal chromosomal karyotype on the pregnancy outcomes of recurrent miscarriage (RM) couples. Design: Retrospective cohort study. Setting and Population: 3235 RM couples who experienced two or more miscarriages before 20 weeks were diagnosed in our tertiary referral unit of a university hospital during 2008 to 2018. Main Outcome Measure(s): The frequency and distribution of 121 carriers were described. Pregnant RM carriers (n=55) and non-carriers (n=229) were compared in the etiological factors and pregnancy outcomes. Result(s): Chromosome aberration was detected in 121 (3.74%) among 3235 RM couples which included 75 female and 46 male cases at an individual level. 101 cases were structural aberrations including balanced translocations in 46(38.0%) cases, Robertsonian translocations in 13(10.7%) cases, inversions in 42(34.7%) cases and 20(16.5%) cases were numerical aberrations. 121 carriers during 2008 to 2018 and 428 non-carriers in the 2018 were followed up for two years. 55 carriers and 229 non-carriers were subsequent pregnant after diagnosis by natural conception or intrauterine insemination. The frequency of carriers to have a health newborn was not significantly different with non-carriers (72.7% vs. 71.2%, adjusted p=0.968). Conclusion(s): This study described the majority of carriers were balanced translocations and chromosome aberrations had a limited influence on live birth rate from the present data. The results of the study also remind us that natural conception may be also a good alternative rather than PGD (Pre-implantation Genetic Diagnosis) which is common in many other reproductive centers for such patients.

Background Parental abnormal chromosomal karyotypes are considered as reasons for recurrent pregnancy loss. Objective This systematic meta-analysis evaluated the current evidence on pregnancy outcomes amongst couples with abnormal versus normal chromosomal karyotypes. Search strategy Two independent reviewers screened titles and abstracts identified in EMBASE and PubMed from inception to January 2021. Selection criteria Studies were included if they provided a description of pregnancy outcomes of parental chromosomal abnormality. Data collection and analysis Random effects meta-analysis was used to compare odds of pregnancy outcomes associated with noncarriers and carriers. Main results A significantly lower first pregnancy live birth rate (FPLBR) was found in carriers than in noncarriers with RPL (OR: 0.55; 95% CI: 0.46-0.65; p<0.00001). Regarding FPLBR between translocation or inversion carriers and noncarriers, a markedly decreased FPLBR was found in translocation (OR: 0.44; 95% CI: 0.31–0.61; p<0.00001) but not inversion carriers. The accumulated live birth rate (ALBR) (OR: 0.96; 95% CI: 0.90–1.03; p=0.26) was similar, while the miscarriage rate (MR) of accumulated pregnancies (OR: 2.21; 95% CI: 1.69–2.89; p<0.00001) was significantly higher in the carriers than in noncarriers with RPL. The ALBR was not significant (OR: 1.82; 95% CI: 0.38–8.71; p=0.45) but the MR (OR: 5.75; 95% CI: 2.57–12.86; p<0.0001) was markedly lower for carriers who choose PGD than natural conception. Conclusions Carriers with RPL had higher risk of miscarriage but obtained a satisfying pregnancy outcome through multiple attempts. No sufficient evidence was found PGD could enhance the ALBR but it was an alternative to decrease the MR.