Association between time from endometriosis surgery and outcome of in vitro fertilization cycles

To evaluate the effect of time from surgery on the outcome of subsequent in vitro fertilization (IVF) cycles in endometriosis patients.

One hundred five women treated surgically for endometriosis and who underwent 252 IVF cycles were included. Approximately 1/2, 1/4 and 1/5 of the study group underwent 1, 2 and 3 cycles, respectively. We used the cycle as the basic unit of analysis with the time since surgery as the independent variable and the clinical pregnancy as the dependant variable. We used nonparametric approach for estimating the probabilities. To convey the uncertainty of the probability estimates, we produced bootstrap 95% CI.

The overall pregnancy rate was 31%. There does not appear to be any relationship between the length of time from surgery and clinical outcome. The point estimates suggest that there may be a slight negative relationship, since the estimated probability decreases steadily from 0.34 to 0.21 as the time since surgery goes from 0.5 to 5 years.

The data do not provide evidence for a strong relationship between the time since surgery and the probability of a clinical pregnancy with IVF.