Infertility and ectopic pregnancy risk

Infertility due to abnormalities of the fallopian tube or uterus raises the risk that in vitro fertilization (IVF) or other assisted reproductive techniques (ART) will result in an ectopic pregnancy, in which the fertilised egg attaches itself outside the normal uterus location. Ectopic pregnancies typically occur in the fallopian tubes, thus they're sometimes called tubal pregnancies. The fetus is unable to grow properly outside the uterus and may actually rupture the fallopian tube, an event that can be fatal for the mother. Early ectopic pregnancies are often treated with drugs to dissolve the fertilized egg, whereas later on, surgical removal of the abnormal pregnancy is often required. Researchers from the Centers for Disease Control and Prevention in Atlanta, USA, analysed outcomes of 94,118 pregnancies, out of which 2.1 percent were ectopic, to investigate the factors associated with ectopic pregnancy risk with ART. According to the researchers, the rate is 2 percent in the general population. It was found that tubal and uterine abnormalities raised the risk of ectopic pregnancy by 38 to 168 percent. Transfer of a fertilised egg into the fallopian tubes, an ART procedure known as ZIFT (zygote intrafallopian transfer), increased the risk of ectopic pregnancy by 75 percent. The risk also rose when three or more embryos were implanted into the mother. Maternal ages, prior spontaneous abortions, use of other types of ART were not significant predictors of ectopic pregnancy. However, as new technologies in ART become available, their potential impact on ectopic pregnancy needs to be investigated.