The value of ultrasound in programmes of in-vitro fertilization is discussed. In order to reach the ovaries, the transvesical route was first introduced, and proved less invasive than laparoscopy. The periurethral route has also been used. The transvaginal approach, especially using a vaginal transducer with an attached needle guide, has attracted many IVF groups and is widely used today. Details of this method are presented. Ultrasound has also been used to assist in the replacement of embryos into the uterus, and the various methods are described.