Etiology of spontaneous abortion before and after the demonstration of embryonic cardiac activity in women with recurrent spontaneous abortion

Objective To analyze the etiologic factors of spontaneous abortion in the first trimester among women with recurrent spontaneous abortion, specifically before and after the demonstration of embryonic cardiac activity. Methods A retrospective analysis included women with recurrent spontaneous abortion admitted to a center in Guangzhou, China, for dilation and curettage after a spontaneous abortion in the first trimester between January 2008 and December 2012. The etiologic factors of spontaneous abortion occurring before versus after the demonstration of cardiac activity were compared. Results A total of 232 women were included. Among 146 women with demonstrated cardiac activity before spontaneous abortion, 78 (53.4%) had an embryonic karyotype abnormality, 55 (37.7%) had traditional etiologic factors, and 34 (23.3%) had an unidentified cause. Among 86 women without cardiac activity, 41 (47.7%) had an embryonic karyotype abnormality, 28 (32.6%) had traditional etiologic factors, and 26 (30.2%) had an unidentified cause. After exclusion of abortions involving embryonic karyotype abnormalities, there was a higher incidence of APA positivity in the group with embryonic cardiac activity than in the other group (13/68 [19.1%] vs 1/45 [2.2%]; P = 0.008) and a lower incidence of subclinical hypothyroidism (8/68 [11.8%] vs 12/45 [26.7%]; P = 0.042). Conclusion The distribution of etiologic factors in spontaneous abortion differs according to whether embryonic cardiac activity is recorded.