In IUI, specially prepared sperm is placed directly inside the uterus around the time of ovulation, and fertilization occurs naturally inside the body. In IVF, eggs are retrieved from the ovaries and fertilized with sperm in a laboratory before an embryo is transferred into the uterus. The choice between IUI and IVF depends on factors such as age, fertility diagnosis, sperm parameters, fallopian tube health and previous treatment history.
