Fertilization outside the body

Hormone injections stimulate oocyte maturation adapted to the individual. Several oocytes become mature to be collected for in vitro fertilization.
After fertilization - which takes place when the prepared sperm cells come together with the oocytes in a Petri dish-the embryos are transferred 2-5 days later in the uterus.
Usually, for women under thirty-five a maximum of two embryos are transferred or even just one blastocyst is transferred with a thin transfer catheter to the uterus.