Imaging plays an important role in both obstetrics and gynaecology. Ultrasound is extremely valuable at all stages of pregnancy: early in pregnancy for viability and establishing gestation, mid-pregnancy to look for fetal abnormality and later in pregnancy, for growth, well-being and presentation. Ultrasound is also very useful in gynaecology to assess both the uterus and the ovaries, and further information can be obtained with computed tomography (CT) and magnetic resonance imaging (MRI) if required. Other uses of imaging will also be discussed.

Ultrasound is an excellent modality for pregnancy. In particular, it has a rapid acquisition time (useful when movement is present), is portable and convenient (can be used in labour ward if required), is almost certainly extremely safe and is socially acceptable. Its accessibility, however, occasionally means that there is a temptation for untrained practitioners to use it and, although good images can easily be obtained, interpretation is often quite subtle – even in simple terms of orientation.