Multivariate logistic regression analysis predicting risk factors for OP
| Adjusted OR1 (95% CI)* | ||
|---|---|---|
| OP vs TP | p Value | |
| Serum Chlamydia trachomatis IgG test | <0.01 | |
| Negative | Ref | |
| Positive | 0.17 (0.06 to 0.52) | |
| Mode of pregnancy | 0.02 | |
| Natural conception | Ref | |
| Other ART | NA | |
| IVF-ET | 12.18 (2.23 to 66.58) | |
| Previous adnexal surgery | 0.04 | |
| No | Ref | |
| Yes | 0.25 (0.07 to 0.95) | |
| Current contraceptive experience | 0.03 | |
| Non-users | Ref | |
| Intrauterine device | 1.42 (0.39 to 5.18) | |
| Oral contraceptive pills | NA | |
| Female sterilisation | NA | |
| LNG-EC | 0.24 (0.07 to 0.78) | |
| Other contraceptive methods† | 0.34 (0.03 to 0.87) |
*OR1 refers to the OR for OP when using TP patients as control. All ORs were adjusted for the other variables included in table 3, as well as age and occupation.
†Other contraceptive methods included condoms, the rhythm method and withdrawal.
LNG-EC, levonorgestrel emergency contraceptive; NA, not applicable; OP, ovarian pregnancy; Ref, reference; TP, tubal pregnancy.