Ultrasound examination is as effective a diagnostic test as hysteroscopy or laparoscopy for the diagnosis of uterine abnormalities. Three-dimensional ultrasound has been used to assess uterine anatomy and to detect congenital anomalies of the uterus. Ultrasound examination is used to monitor endometrial growth and ovarian response to the medical treatment. Appropriate endometrial growth indicates good endometrial receptivity. Appropriate ovarian response to gonadotrophin stimulation increases the chances that good quality eggs will be released in ovulation induction cycles and that good embryos will be available for embryo transfer in in vitro fertilisation (IVF) cycles. Ultrasound is also used to monitor embryo transfer. Both greyscale ultrasound examination of the endometrium and Doppler ultrasound examination of the uterine arteries have been used to assess 'endometrial receptivity' in IVF cycles. Ultrasound greyscale imaging is regarded as sufficiently accurate to be used alone for monitoring follicular growth during gonadotrophin therapy.