Sample size calculation
We calculated sample-size by two independent proportions. Using the
estimated livebirth rate of 25% with neosalpingostomy and 53% with
salpingectomy based on previous literature, and assuming an alpha level
of 0.05 for two-sided test, we calculated that a sample of 88 cases who
underwent therapy would result in 80% power (1:1 ratio). The sample
size was increased to 110 (two groups of 55) to allow for a 20% rate of
loss to follow-up over the long time period.