Main trends of research in the social and human ... - unesdoc - Unesco

360 Jean Bourgeois-Pichat
21. The frequency of sexual intercourse obviously does not depend on biologi-
cal factors alone; social and psychological factors play an equally important
part. Still, biology certainly has its say in the matter. Moreover, all things being
equal, sexual desire weakens with age. But here again, we are totally ignorant
of the mechanism of this weakening. W e do not even know its extent. Informa-
tion collected around 1950 concerning 6,300 American women and around
1957 concerning 600 Japanese women - that is all we have at present for the
entire human race.
22. But especially the effectiveness of sexual intercourse depends very much on
the length of time during which the ovule can be fertilized in the course of a
woman’s menstrual cycle. The length of life of the ovule, once it has been emitted,
and that of the spermatozoa deposited in the woman’s genital organs are com-
bined in such a way that fertilization is only possible during a few days in
each cycle. But we do not know how this combination is brought about, nor do
we know the result. It it one, two or three days? The experts argue the matter
without being able to reach any agreement.
23. We have spoken so far of woman’s infertility; but, actually, it is the infer-
tility of the couple which the demographer tries to evaluate, and which is the
result of either the man’s or woman’s infertility, or again a combination of the
two, with each partner able to be fertile in a different combination. One day the
demographer will really have to distinguish between these three types of in-
fertility, but that will necessitate a prior reorganization of the statistics. At the
same time biology will have to enlighten us as to the mechanism producing
masculine sterility and that of the sterility of the couple when each of the two
constituents is fertile. All the biological problems connected with increasing
infertility with age and with infertility at the beginning of puberty need to be
studied separately as regards the male, the female and the couple.
24. The questions we have been led to raise in the course of this report concern
all those fields in which the demographer - who specializes in the biological
aspects of fertility- ought to direct his researches during the next few years. The
World Health Organization clearly sees the importance of this, and has set on
foot a research programme covering all these aspects.
Contraceptive practices
25. We have assumed that couples were not practising contraception. The prac-
tice of contraception is going to raise new problems. It is going to do even more
than that: under its influence the very nature of the problems is going to be
changed. W e meet again with the idea expressed at the beginning of this report
showing how man is caught up in the evolutionary process of living species and
how demographic events, by sharing in this evolution, change their nature
through the ages. The populations which do not make use of contraceptive
methods are far from using all the possibilities that biology offers them. By re-
tarding the marriage age, and with the help of celibacy and sexual taboos, these