This book investigates the scientific validity and practical application of the Shettles Method for influencing the biological sex of a child through timing and environmental control. Dr. Landrum B. Shettles, a pioneer in reproductive biology, presents his hypothesis regarding the differential motility and survival rates of X- and Y-bearing spermatozoa. The text outlines a specific protocol for couples to follow, utilizing data from his clinical observations and laboratory research to support his claims about conception timing and vaginal pH levels.

The subject matter points to a highly controversial and debated approach within the field of reproductive medicine, as many subsequent studies have failed to replicate the author's original findings. The framing suggests a guide intended for laypeople seeking to influence biological outcomes, though it remains a subject of significant skepticism among modern medical professionals.