Systematic meta-analysis of subsequent pregnancy outcomes in recurrent
pregnancy loss couples with parental abnormal chromosomal karyotype
Abstract
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.