Seventy-two thousand labor histories for a period of several years from 5 different obstetrical institutions of two geographical regions of the Soviet Union were subjected to retrospective analysis. Significant influence of preceding induced abortion on the sex ratio is shown. In all five samplings the total sex ratio among primi- and multiparae with no abortions in anamnesis was 106.8♂:100♀. When infants are born within 1 year, 1-2 years, 2 years and more after an artificial abortion the sex ratio is: 76:4♂:100♀ (p < 0.001); 91.2♂:100♀ (p < 0.001); 125.2♂:100♀ (p < 0.001) respectively. Spontaneous abortions do not affect the sex ratio. Preponderance of female infants after an artificial abortion may be explained by selective survival of female embryos connected with heterosis by X-chromosome.
Golovachev, G D.; Allipov, V I.; Novikova, L N.; and Taptunova, A I.
"The Effect of Artificial and Spontaneous Abortions on the Secondary Human Sex Ratio,"
4, Article 12.
Available at: https://digitalcommons.wayne.edu/humbiol/vol52/iss4/12