at if
child-bearing is postponed till after thirty, in a certain number of
families no children are born. There are many men and women who
bitterly regret having let the years go by in which children might
have been born to them, and it is only fair that young couples of
to-day should fully understand this risk.

CHAPTER III

METHODS

There are certain points in regard to methods of preventing conception
which should be made clear.

It is, of course, obvious that conception can be voluntarily
controlled by abstention from intercourse except when children are
desired. This has been called a counsel of perfection. It could only
rightly be so described where such a method of life was both desired
and approved by both husband and wife. It would not be a fair thing
for either to enforce a practically celibate life on the other without
the fullest understanding and consent before the marriage vows were
taken.

But conception can also be controlled by avoidance of those parts of
the monthly cycle in which conception most commonly takes place. That
in the great majority of women there is a time in the monthly cycle
when no conception occurs has been noted for a long time. The
rough-and-ready method of reckoning the date of birth in relations to
the last menstrual period is an example of the assumption that
conception will probably have taken place a week later, and the
frequency with which such reckoning is justified shows that it is not
altogether unfounded. During the war it was possible to make some more
exact observations owing to the short leave granted to soldiers to
visit their homes. Seigel has published a paper in the "Muenchener
Medizinische Wochenschrift," 1916, in which he gives information
regarding the conception of between two and three hundred children
born during the war. He finds that the likelihood of fertilisation
increases from the first day of menstruation, reaching the highest
point six days later, the fertile period remains almost at the same
height till the 12th or 13th day, and then declines gradually until
the 22nd day, after which there is absolute sterility.

This suggests that conception control can be attained without
artificial methods if intercourse is confined to one week in the
month.

Such control of conception, though natural, does not make it any more
desirable to space the births unduly so that the children are brought
up in separate units instead of in a happy family gr