Galen: On the Natural Faculties by Galen
Chapter III
Exercise of the retentive faculty particularly well seen
in the uterus. Its object is to allow the embryo to
attain full development; this being completed, a new
faculty--the expulsive--hitherto quiescent, comes into
play. Characteristic signs and symptoms of pregnancy.
Tight grip of uterus on growing embryo, and accurate
closure of os uteri during operation of the retentive
faculty. Dilatation of os and expulsive activities of
uterus at full term, or when foetus dies. Prolapse from
undue exercise of this faculty. _Rôle_ of the midwife.
Accessory muscles in parturition.