Pregnancy is not a morbid condition; on the contrary, a pregnant woman is at the climax of her most normal physiological life, but owing to the tension thus involved she is specially liable to suffer from any slight shock or strain.
It must be remarked that the increased tendency to premature birth, while in part it may be due to general tendencies of civilization, is also in part due to very definite and preventable causes.

Syphilis, alcoholism, and attempts to produce abortion are among the not uncommon causes of premature birth (see, e.g., G.F.McCleary, "The Influence of Antenatal Conditions on Infantile Mortality," _British Medical Journal_, Aug.

13, 1904).
Premature birth ought to be avoided, because the child born too early is insufficiently equipped for the task before him.
Astengo, dealing with nearly 19,000 cases at the Lariboisiere Hospital in Paris and the Maternite, found, that reckoning from the date of the last menstruation, there is a direct relation between the weight of the infant at birth and the length of the pregnancy.

The longer the pregnancy, the finer the child (Astengo, _Rapport du Poids des Enfants a la Duree de la Grossesse_, These de Paris, 1905).
The frequency of premature birth is probably as great in England as in France.

Ballantyne states (_Manual of Antenatal Pathology; The Foetus_, p.