To investigate whether thyroid autoimmunity (TAI) is associated with increased risk for spontaneous miscarriage in subfertile, euthyroid women undergoing IVF.
Meta-analysis of observational studies.
Four prospective studies that reported data on 1098 subfertile women undergoing IVF (141 with TAI and 957 controls) were included in the meta-analysis.
Main outcome measure
Miscarriage risk ratio (RR).
Secondary outcome measures
Clinical pregnancy rate and delivery rate.
Euthyroid, subfertile women with TAI undergoing IVF demonstrated significantly higher risk for miscarriage compared with controls (four studies–fixed effects RR: 1.99, 95% confidence interval: 1.42– 2.79, P<0.001). No significant difference in clinical pregnancy and delivery rates was detected between groups.
Based on the currently available evidence, it appears that the presence of TAI is associated with an increased risk for spontaneous miscarriage in subfertile women achieving a pregnancy through an IVF procedure.