Idiopathic recurrent pregnancy loss recurs at similar gestational ages

To determine whether a correlation exists between gestational ages of idiopathic recurrent pregnancy loss (iRPL).

Cohort of women with iRPL who had an initial loss (qualifying pregnancy [QP]) with precise documentation of gestational age. Outcomes in the immediate next pregnancy (index pregnancy [IP]) were compared between preembryonic (group I), embryonic (group II), or fetal (group III) losses in the QP.

Three hundred thirty-four women met inclusion criteria. In their IP, group I had 41% preembryonic, 28% embryonic, and 10% fetal losses. Group II had 14% preembryonic, 53% embryonic, and 9% fetal losses. Group III had 19% preembryonic, 23% embroyonic, and 29% fetal loses. Correlation coefficient for type of loss among the QPs and IPs was 0.14, P = .009.

Women with iRPL tend to have losses recur in the same gestational age period. Causes for RPL may be gestational age specific and should guide further investigations into causes.