The Shettles Method is a popular, non-medical approach to conception that attempts to influence the sex of a child through specific intercourse techniques and timing. Developed by Dr. Landrum Shettles in the 1960s, the method focuses on exploiting theoretical differences between X and Y sperm to favor one type over the other. This approach does not involve medical intervention or laboratory procedures, making it accessible to any couple trying to conceive.
The Underlying Biological Theory
The foundation of the Shettles Method rests on the idea that X and Y sperm possess distinct characteristics. Y-sperm (male) are theorized to be smaller, faster, and more fragile with a shorter lifespan. Conversely, X-sperm (female) are thought to be slower, larger, and more resilient, surviving longer within the female reproductive tract.
The method also incorporates the concept of the vaginal and cervical pH level acting as a natural filter. Y-sperm are hypothesized to thrive in a more alkaline environment, like the cervical mucus present close to ovulation. X-sperm are believed to be more durable in the more acidic environment of the vagina, which is present in the days leading up to ovulation.
Implementing Strategies for Conceiving a Boy
To increase the chances of conceiving a boy, the Shettles Method recommends favoring the faster, less durable Y-sperm. The primary strategy involves timing intercourse to occur as close as possible to the moment of ovulation. This timing allows the Y-sperm to use their speed advantage to reach the egg quickly before their short lifespan ends.
Another recommended technique is the use of deep penetration positions, such as rear-entry. Deep penetration aims to deposit the sperm closer to the cervix, bypassing the acidic conditions of the upper vagina and placing them directly into the more alkaline cervical mucus. The method also suggests that a female orgasm may increase the alkalinity of the environment, further aiding the Y-sperm. Additionally, couples are advised to abstain from intercourse for several days beforehand to allow the male partner’s sperm count to build up.
Implementing Strategies for Conceiving a Girl
To improve the likelihood of conceiving a girl, the strategy is reversed to favor the slower, more resilient X-sperm. This involves timing intercourse two to four days before the expected day of ovulation, followed by abstinence until after ovulation has passed. By having intercourse several days prior to the egg’s release, the faster Y-sperm are theorized to die off, leaving the hardier X-sperm to wait for the egg.
Shallow penetration positions, such as the missionary position, are suggested to deposit the sperm closer to the vaginal opening. This forces the sperm to travel a longer distance through the acidic vaginal environment, which is believed to be detrimental to the Y-sperm. The method also recommends that the female partner avoid orgasm, as the alkaline secretions associated with climax are thought to create a more favorable environment for the Y-sperm.
Scientific Assessment of Effectiveness
While the Shettles Method is widely known, the modern scientific community generally views its effectiveness with skepticism. The underlying premise that X and Y sperm have distinct characteristics regarding speed and resilience is partially supported by some biological observations. However, the claimed success rates, which Dr. Shettles reported to be as high as 75% to 80% based on anecdotal evidence, have not been consistently replicated in rigorous clinical trials.
The lack of consistent evidence means the method is often considered only marginally more effective than the natural 50/50 chance of conceiving a boy or a girl. Some studies conclude that the timing of sexual intercourse in relation to ovulation has no measurable influence on the sex of the baby. The method remains a popular, harmless option for couples, but it should not be relied upon as a guaranteed way to select a child’s sex.