Fifteen week old foetus. Ultrasound scan of a human foetus in side view, 15 weeks (3.5 months) old. The head is at left facing up; the torso at right. At this age the foetus appears completely human and its nose, mouth, chin, and external ear, are seen. Part of an arm is visible at upper right. Fingers and toes are formed at this age, and the foetus is covered in fine hair while eyebrows and head hair are forming. The crown- rump length (sitting height) of the foetus is about 13-14cm and its weight about 180-200g. The head is proportionately large although the body is elongating at this stage. The sex of the foetus is well established, although not seen here.