The adverse effect of a previous late miscarriage on the subsequent
pregnancy outcomes: a retrospective cohort study across more than ten
years.
Abstract
Objective To explore whether a previous late miscarriage(LM) has a
prognostic impact on the subsequent pregnancy outcomes in in-vitro
fertilization(IVF) women. Design Retrospective cohort study. Setting
Reproductive medicine centre at a tertiary hospital Population 1072
infertile women who had a LM following first embryo transfer. Methods
Women were grouped by the causes of LM, 458 women with unexplained
factor(unLM), 146 women with fetal factor(feLM), 412 women with cervical
factor(ceLM), 56 women with trauma factor(trLM). Subgroup analysis and
binary logistic regression were performed to evaluate the associations
between LMs with different causes and subsequent pregnancy outcomes.
Main outcome measures The frequency of live birth and miscarriage
following the subsequent embryo transfer after LM. Results Compared with
general IVF population, the early miscarriage rate was significantly
higher in unLM group(8.28% vs. 13.47%,P=0.003, rate
ratio(RR)=1.725,95% confidence interval(CI)1.204-2.470). Further, women
with a unLM or ceLM had a dramatically elevated risk of recurrent LM(for
unLM:4.24% vs. 9.43%,P=0.000,RR=2.348,95%CI 1.527-3.610; for ceLM:
4.24% vs. 15.53%,P=0.000,RR=4.147,95%CI 2.836-6.064) and a
consequently reduced frequency of live birth(for unLM: 49.96% vs.
43.01%,P=0.005, RR=0.756,95%CI 0.622-0.918; for ceLM: 49.96% vs.
38.59%,P=0.000,RR=0.629,95%CI 0.512-0.774). Conclusions Only one
previous LM resulted from unexplained factor or cervical factor was
significantly associated with a higher risk of miscarriage and a lower
live birth rate after the subsequent embryo transfer. Keywords Late
Miscarriage/Live Birth/Early Miscarriage/Cervical Incompetence/In Vitro
Fertilization Tweetable abstract Women who had a LM for unexplained
factor or cervical factor following the first embryo transfer had a
significantly poor pregnancy prognosis after the subsequent transfer.