Abstract: Objective: To evaluate the detections of antinuclear antibody (ANA), anticardiolipin antibody (ACL) and anti-β2 glycoprotein 1 antibody (aβ2GP1) in patients with moderate and severe endometriosis before IVF/ICSI treatment. Methods：From January 2018 to April 2019, 86 patients with moderate and severe endometriosis (EMs group, 86 cases) and 82 women who were planned to undertake IVF/ICSI treatment due to male factors (control group, 82 cases) were collected as the subjects. The level of serum ANA was detected by immunofluorescence, and the levels of ACL and aβ2GP1 antibodies were detected by enzyme-linked immunosorbent assay. Results：The total positive rate of at least one antibody positive in the EMs group was 31.40% (27/86), while that in the control group was 12.19% (10/82). The difference between the two groups was statistically significant (P＜0.05); The total positive rate of ANA in the EMs group [5.81% (5/86)] was slightly higher than that in the control group [1.22% (1/82), but P＞0.05]. The total positive rate of ACL in the EMs group [13.95% (12/86)] was also slightly higher than that in the control group [6.10% (5/82), but P＞0.05]. Interestingly, the total positive rate of aβ2GP1 in the EMs group [16.28% (14/86)] was significantly higher than that in the control group [6.10% (5/82), P＜0.05]. Conclusions：The combined screening of serum ANA, ACL and aβ2GP1 is recommended for patients with moderate and severe endometriosis before IVF/ICSI treatment. The positive rate of aβ2GP1 in patients with moderate and severe endometriosis is high, which deserves clinical attention.

Key words: Antibodies, antinuclear；Anti-nuclear antibody；Antibodies, anticardiolipin；Antibodies, antiphospholipid；, Anti-β2-glycoprotein 1 antibody；, Endometriosis；, Enzyme-linked immunosorbent assay；, Fluoroimmunoassay