Takeaway
- Tubal factor and pelvic surgery other than caesarean delivery were independently associated with the risk of developing ectopic pregnancy (EP) following in vitro fertilisation-embryo transfer (IVF-ET).
- Endometrial thickness >12 mm prior to embryo transfer and more transferable embryos were protective factors against EP.
Why this matter
- The risk for EP after IVF-ET is higher than after spontaneous conception, however, there is no clarity on the risk factors associated with this increased risk.
Study design
- This case-control study included 225 women with EPs (cases) and 900 matched women with intrauterine pregnancies (controls).
- Outcome: endometrial thickness.
- Funding: Fundamental Research Funds for the Central Universities (China).
Key results
- Pelvic surgery other than caesarean delivery (OR, 2.07; 95% CI, 1.34-3.19; P=.001) and tubal factor (OR, 1.61; 95% CI, 1.12-2.31; P=.01) were significantly associated with a higher risk for EP.
- Endometrial thickness >12 mm before embryo transfer (OR, 0.267; 95% CI, 0.13-0.56; P<.001) and the number of transferable embryos (OR, 0.71; 95% CI, 0.65-0.78; P<.001) were protective factors against EP.
- The area under the curve of the endometrial thickness (AUC, 0.60; 95% CI, 0.56-0.64; P<.001) and the number of transferable embryos (AUC, 0.68; 95% CI, 0.64-0.72; P<.001) for EP prediction were higher than those for tubal factor (AUC, 0.55; 95% CI, 0.51-0.59; P=.018) and pelvic surgery other than caesarean delivery (AUC, 0.58; 95% CI, 0.54-0.63; P<.001).
- Gn dosage and duration, the number of oocytes retrieved, IVF, the number of transferred embryos, the hCG level after embryo transfer, day 3/day 5 (D3/D5) embryo transfer and fresh/frozen embryo transfer did not have a significant effect on the risk of developing EP.
Limitations
- Observational design could not establish causality.
References
References
