An analysis of factors associated with ectopic pregnancy in a human in vitro fertilization program.

Between 1980 and 1985, in Monash University in vitro fertilization (IVF) program, ectopic pregnancy occurred in 10 of 256 IVF pregnancies. The incidence of ectopic pregnancy between 1983 and 1984 was 4% of the total pregnancies, or 4.2% of pregnancies excluding biochemical pregnancies. The incidence of ectopic pregnancy was distributed equally across the infertility classifications (tubal, idiopathic, male factor, and mixed). There appeared to be no relationship between superovulatory methods, endocrine changes before egg recovery, laparoscopic procedures, embryo transfer procedures, and number of embryos transferred. Nine of the ten patients were classified as having either tubal factor infertility before IVF or chronic tubal inflammation, which probably existed at the time of embryo replacement. No ectopic pregnancies were recorded in the 33 pregnancies obtained with superovulation with the use of clomiphene citrate alone. We were unable to identify a major predisposing factor for ectopic pregnancy in IVF.