her ninth and successive children.

_The age of the woman_ also affects the mortality accompanying
confinement. The age of least mortality is near twenty-five years. On
either side of this, mortality increases with the diminution or increase
of age. The age of the greatest safety in confinement therefore
corresponds to the age of greatest fecundity. And during the whole of
child-bearing life, safety in labor is directly as fecundity, and _vice
versa_. Hence modern statistics prove the correctness of the saying of
Aristotle, that 'to the female sex premature wedlock is peculiarly
dangerous, since, in consequence of anticipating the demands of nature,
many of them suffer greatly in childbirth, and many of them die.' As the
period from twenty to twenty-five is the least dangerous for childbirth,
and as first labors are more hazardous than all others before the ninth,
it is important that this term of least mortality be chosen for entering
upon the duties of matrimony. This we have already pointed out in
speaking of the age of nubility.

_The sex of the child_ is another circumstance affecting the mortality
of labor. Professor Simpson of Edinburgh has shown that a greater
proportion of deaths occurs in women who have brought forth male
children.

_The duration of labor_ also influences the mortality of lying-in. The
fatality increases with the length of the labor. It must be recollected,
however, that the duration of labor is only an inconsiderable part of
the many causes of mortality in childbirth.

WEIGHT AND LENGTH OF NEW-BORN CHILDREN

The average weight of infants of both sexes at the time of birth is
about seven pounds. The average of male children is seven and one-third
pounds; of female, six and two-thirds pounds. Children which at full
term weigh less than five pounds are not apt to thrive, and usually die
in a short time.

The average length at birth, without regard to sex, is about twenty
inches, the male being about half an inch longer than the female.

In regard to the relation between the size of the child and the age of
the mother, the interesting conclusion has been arrived at, that the
average weight and length of the mature child gradually increases with
the age of the mother up to the twenty-fifth year. Mothers between the
ages of twenty-five and twenty-nine have the largest children. From the
thirtieth year they gradually diminish. The first child of a woman is of
comparatively light weight. T