Prenatal Mortality and the Birth-Rate

Abstract

MAXIMUM reproductivity in a monogamous society requires that males and females of appropriate age shall be available in approximately equal numbers. A considerable excess of one sex or the other will decrease the reproduction-rate. In practice, there rarely seems to be an excess of males of this age; among European races a slight excess of females is usual.War, or other events involving a differential toll of men of reproductive age, naturally exaggerate the excess of females. In England and Wales before the War of 1914–18¹, there was an excess of some 649,000 or 8·7 per cent of females over males, at ages 20—45 years. For several years after 1918 the excess was more than a million, being about 1,050,000, or 13·4 per cent in 1925². Ten years later, in 1935³, the effects of the war were disappearing and the excess of females was down to 658,000, or 7·9 per cent, but it may well increase again considerably as a result of the present War. The surplus women, on statistical grounds alone, are evidently unable to get married in Great Britain, and the great majority of them, therefore, are sociologically sterilized. The number represents an appreciable percentage of the females of reproductive age, and this sociological sterility is a not inconsiderable factor in birth-rate problems. Groome⁴ calculated that an increase in the net reproduction-rate of some 15 per cent would be expected to result from equalizing the numbers of males and females of reproductive age, even without any increase in the total population.