LAUSR

STUDY OBJECTIVE To investigate whether there are left-right asymmetries, factors affecting lateral dominance, and clinical feature differences in the left and right sides of tubal pregnancy (TP). DESIGN Retrospective study (Canadian Task Force classification II-2). SETTING International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University. PATIENTS Patients (n = 6186) with TP treated surgically. INTERVENTIONS We used data from the digital medical records system of the hospital. Women diagnosed with ectopic pregnancy(EP) between January 2005 and December 2016 in the inpatient department of gynecology were included. All data from the medical files were obtained retrospectively, including demographic characteristics; reproductive, gynecologic, and surgical history; clinical features; and treatment. Patients who were previously treated by salpingectomy or nonsurgical management and those with unknown-site EP or non-TPs were excluded. MEASUREMENTS AND MAIN RESULTS The overall frequency of right-sided TP was 54.48% (3370/6186), which is significantly higher than 50% (p < .001, binominal test). The proportion of right-sided TPs decreased with age (p for trend = .007) and from the proximal (interstitial) end to the distal (fimbrial) end of the tube (p for trend = .017). Of the TP patients with a corpus luteum, we found the corpus luteum was more frequently located in the right ovary (p < .001) and in the contralateral ovary to the TP side in 41.38% of cases. However, tubal rupture was more frequent in left TP than the in right TP (p = .005). CONCLUSION The left-right asymmetries of TP include right-side dominance and the clinical feature differences between the 2sides of TP.