Pathogenesis
In the general population, the major risk factors for heterotopic pregnancy are the same as those for ectopic pregnancy. For women in an assisted reproductive program, there are additional factors: a higher incidence of multiple ovulation, a higher incidence of tubal malformation and/or tubal damage, and technical factors in embryo transfer which may increase the risk for ectopic and heterotopic pregnancy.
Read more about this topic: Heterotopic Pregnancy