In vitro fertilization. Conceptual computer artwork of in vitro fertilization (IVF), showing male and female figures on jigsaw pieces above an ultrasound scan. The incompatibility of the two jigsaw pieces represents their infertility. In IVF, eggs are surgically removed from a woman and fertilized with male sperm in a dish. Several embryos are then placed into the woman's uterus to continue their development. Ultrasound images are produced from the echoes of high-frequency sound waves that are transmitted into the body. Ultrasound can be used to follow the growth of developing foetuses, or to check if structural abnormalities are causing a woman to be infertile.