Maternal antithyroid antibodies and euploid miscarriage in women with recurrent early pregnancy loss.

OBJECTIVE

To determine whether an association exists between maternal antithyroid antibodies and euploid miscarriage in women with recurrent early pregnancy loss (REPL).

DESIGN

Observational cohort study.

SETTING

Two academic medical centers.

PATIENT(S): Women seen between 2004-2015 with a history of REPL, who were euthyroid or had subclinical hypothyroidism, had maternal antithyroid antibody testing and had at least one subsequent early pregnancy loss (<10 weeks' gestation).

INTERVENTION(S): Thyroid function and antibodies were measured at consultation. Subsequent miscarriages were assessed by conventional cytogenetic analysis, and when indicated, microsatellite analysis and/or comparative genomic hybridization/single nucleotide polymorphisms were performed.

MAIN OUTCOME MEASURE(S): Determine whether maternal antithyroid antibodies are associated with euploid miscarriage.

RESULT(S): Cohort consisted of 74 subjects with REPL who had 130 subsequent early pregnancy losses. The prevalence of maternal antithyroid antibodies in the cohort was 17.6%. Mean TSH was significantly higher among subjects with maternal antithyroid antibodies. Otherwise, no significant differences in demographics were noted. When comparing types of early pregnancy losses between the two groups, a trend toward having more miscarriages than nonvisualized pregnancy losses was noted among subjects with maternal antithyroid antibodies (70% and 30%) compared with subjects without maternal antithyroid antibodies (55% and 43%). No significant difference was noted in the frequency of euploid miscarriage between subjects with and without maternal antithyroid antibodies (42% vs. 56%).

CONCLUSION(S): Our study did not demonstrate an association between euploid miscarriage and maternal antithyroid antibodies in subjects with a history of REPL. Therefore, testing or treatment in this cohort may not be warranted.