Obstetrics. This term derived from the Latin obstetrix," a midwife," literally "one who stands by," is applied to the science and art of the treatment of childbirth, and the abnormal conditions and diseases associated with the same. This branch of medical knowledge has undergone wonderful development in the last two centuries. The ancient physicians devoted, it is true, some attention to the subject, but their notions were crude, and their practice necessarily therefore far from perfect. Throughout the Middle Ages scarcely any advance was made; men were jealously precluded from all study of the problems involved, and ignorance and superstition reigned supreme. In the 17th century, however, a new science of obstetrics gradually came into being, and systematic study was devoted to the subject, with the result that it is now an everyday occurrence for the life of an infant or of a mother to be saved by the art of the obstetrician. In the large majority of cases labour is naturally performed without any artificial aid; but in some instances, whether it be from anomaly of the uterine contractions, from deformity of the pelvis, or from abnormality of the foetus, the unaided natural forces are unequal to the task of delivering the child. An important advance was marked by the discovery of the forceps by the Chamberlens early in the 17th century, and the instrument has undergone improvement from time to time. By means of the traction exerted by the forceps it is often possible to satisfactorily terminate labour in cases which without the assistance of the instrument would be fraught with danger to the mother or child or both. Sometimes version, i.e. the bringing about of a change in the presentation of a child, requires to be effected; and in rare instances when it is impossible to deliver a living child, the operation of craniotomy is performed. The induction of premature labour is indicated in cases of extreme pelvic contraction. The expulsion of the after-birth is sometimes attended with difficulty, and disturbed contraction of the uterus after delivery may lead to bleeding (post partum haemorrhage, as it is called), which is one of the most urgent conditions that a surgeon can be called upon to deal with. The use of anaesthetics has greatly facilitated the performance of obstetric operations and has materially diminished the difficulties in the treatment of labour. Puerperal fever, which in former days claimed many victims, is now, thanks to the use of antiseptics, comparatively rare.