Natural family planning and sex selection: fact or fiction?

Gray, R H · Am J Obstet Gynecol · 1991

meta_analysis · Level I

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Abstract

Determining sex of offspring by timing of intercourse has been a subject of intense interest for the lay public and professional community. This metaaanalysis of couples practicing natural family planning provides an opportunity to evaluate sex ratios in relation to the timing of conception with several parameters, including basal body temperature shift and peak mucus as markers of ovulation. Data from six studies show a statistically significant lower proportion of male births among conceptions that occur during the most fertile time of the cycle.

Medical subject headings