In vitro fertilization is a medical procedure used when a pregnancy is not occurring on its own. Eggs are collected and combined with sperm in a laboratory. If an embryo forms, it is placed in the uterus.
The Steps in the Procedure
- Stimulation. Medication brings several eggs to maturity in one cycle.
- Fertilization. The collected eggs are combined with sperm outside the body.
- Transfer. An embryo that develops is placed in the uterus, and extra embryos may be frozen.
Fertilization Outside the Body and Other Treatments
| Compared | Fertilization Outside the Body | Other Treatments |
| Where egg and sperm meet | In the laboratory | In the body, or not at all if the treatment is medication only |
| An embryo | Observed before it is placed in the uterus | Not handled outside the body |
| A cycle with no embryo | Nothing is placed in the uterus | The treatment may still have been medication alone |