In vitro fertilization—IVF—is the treatment of choice in cases where both fallopian tubes are blocked. However, the technique has been used widely for a number of other conditions such as unexplained infertility, endometriosis and low sperm count.
In IVF, a man's sperm and a woman's eggs are combined in a laboratory dish, where fertilization occurs. The resulting embryo is then transferred into the woman's uterus to develop naturally. Usually, two to four embryos are transferred with each cycle.
IVF involves several steps which are:
- Medications to stimulate the woman's ovaries to form multiple eggs;
- Tracking the development of the eggs in the woman's ovary with blood tests and ultrasound;
- Collecting the eggs from the ovary in an egg retrieval procedure;
- Collection of a semen sample from the male partner; and
- Fertilization of the eggs.
Several days after the eggs have been fertilized, the embryos are transferred to the uterus through the cervix, using a catheter.
The number of embryos to transfer varies. Usually three or four embryos are transferred.