Choosing your Baby's Sex: an Overview of Techniques

Gender Selection Techniques: Choosing the Gender of Your Baby Methods to Influence Whether You Have a Boy Or Girl

Part 2: The Shettles Method: Timing Intercourse & Position [1]
Part 3: Shettles Method: Fertility Charting and Gender Selection [2]

Part 1... While many couples leave the determination of baby gender to fate or to the natural happenstance of biology, other couples desperately seek ways to influence or select the gender of a future child. This is particularly true for Western couples who already have a boy or a girl (or a gaggle of one gender) and wish to "balance" things by having a baby of the opposite sex. Other couples may simply wish to have a modicum of control in determining if their (next) child will be a boy or a girl.

How gender is "decided" biologically is based on the combination of two sex chromosomes that are inherited from the mother and the father. A woman's egg contains an X chromosome and a man's sperms contributes a determining Y or X chromosome. Whether is the child will be a boy or a girl depends on if the sperm from the male contains an X (girl) or a Y (boy). Much gender selection speculation focuses on the different characteristics of "male/Y" or "female/X" sperm, like how fast each type of sperm swims, or how long each sperm type can survive in the womb, or which type of sperm can withstand different pH-levels (acidity) in the vagina.

Methods for determining gender are age old and range from astrological considerations to specialized dietary intake to the vagaries of sexual position to the specific age of the partners who are trying to conceive. For example, the Chinese Gender Calendar is an astrologically-based gender selection chart that cross-references the age of the mother with the month of conception. The gender calendar was discovered in a dynastic royal tomb nearly 1,000 years ago and purports to provide an accurate means to influence gender outcome. That said, there is not a shred of scientific evidence to support the efficacy of the Chinese Gender Calendar or other horoscopic-astrological methods of gender prediction, though at the very least any gender selection technique, no matter how ludicrous or unfounded, can be assumed to have a 50% accuracy rate... To read about gender prediction myths [3], click here [3].

Sexual position is another common source of gender selection theorizing. However, by itself sexual position cannot influence gender: "Gender sexual position" is typically associated with other calendrical methods oriented around timing intercourse on certain days (in relation to when you ovulate). The date of ovulation must be known (or be predictable) for these methods, so fertility charting or developing an ovulation calendar is required. It also helps to have a regular cycle. Depth of penetration during sex is also a factor and coefficient of sexual position. We'll look into these methods when we discuss the Shettles method and how they relate to the characteristics of X (female) and Y (male) chromosome sperm types.

Some claim that diet is a variable in influencing the gender of your baby. A common (and very likely mythological) gender choice method is based on a simple bifurcation between sweet and salty foods. According to this theory, a preconception diet heavy in salty foods will increase the odds of having a boy. A preconception diet dominated by sweet foods is purported to yield girl children. Either way you look at it, this method would appear to pose somewhat of a health risk. Better to heed the words of your doctor and integrate a healthy, balanced diet into your preconception lifestyle!

More recent research suggests that diet (and particularly the mineral component of certain diets) can have an impact on your baby's gender. One study looked close up at the membrane that surrounds the unfertilized egg - the zona pellucida. The zona pellucida is a protective shield around the egg that a sperm must penetrate in order for fertilization to take place. Here, the sperm must "unlock" certain receptors in the pellucid membrane to gain access to the egg's genetic core. To summarize research conclusions, differential ratios of potassium to calcium/magnesium exert an effect on the make-up of the receptor sites or pellucid "locks" that traverse the surface of the egg. These changes in the sperm receptors produce a biological tendency to attract either X chromosome sperm or Y chromosome sperm.

Hence, a preconception diet rich in calcium and magnesium (and low in sodium and potassium) will effectuate changes in the ovum receptor sites that tend to turn away Y sperm and attract X sperm, with a resultant female gender outcome. Conversely, a preconceptional diet rich in sodium and potassium but low in Cal/Mag would have the opposite effect, cultivating an receptor site attraction for Y sperm and a resultant male gender. While this theory may have some theoretical-sounding talk behind it, we recommend talking with your doctor before making any alteration in diet.

Other theories suggest that the pH acidity level in the vagina and cervix can have an effect on the gender of your baby. In short, X or girl sperm, while more robust and slower than Y/male sperm, are more resilient to acidity in the vagina. X's may be slower, but they may also be able to withstand an acidic environment where pH levels "weed out" the male-chromosome sperm. Male or Y sperm are quick and speedy, but weaker, so if knocked out by unfavorable pH levels, the "girl sperm" will onstensibly make it to the egg. High alkalinity, on the other hand, would tend to favor the alacrity of "male sperm", or at least even the pH odds.

The pH level in the vagina may be altered, in theory, by a number of external or naturally-occurring variables. Here, diet could be a factor, as well as the presence of fertile-quality cervical mucus. Healthy cervical mucus around the time of ovulation tends to establish a vaginal pH level that is conducive to general sperm survival. External factors like douching may also have some impact, if this theory is correct, as would products like Pre-Seed or FertileCM. All in all, there is very little science that substantiates either the diet or pH level theories about controlling gender outcome, so be wary of gender slection products that suggest invasive techniques or alterations in a healthy diet regimen.

In a society increasingly enthralled by the economic ideology of the "consumer right to choose", its not surprising that this expression of market freedom/control would saturate other aspects of our lifeworld, including biology and baby gender selection. However, the methods we have cited above are not yet fully or even partially substantiated and most doctors in mainstream research indicate that trying to influence the gender of your baby maybe much closer to fiction than fact. Until human cloning enters the scene in some variation of a Houellebecq dystopia, not even microsorting X and Y sperm type is 100% effective, though the latter is currently close to a sure thing. The only problem with high-tech sperm microsorting is the price tag - around ten grand. With throwing the dice, you already have a 50% chance of getting the gender you prefer, and the cost and effort is substantially less than the X-Y sperm centrifuge treatment.

In Part II of our look at Gender Selection Techniques, we'll look at the Shettles Method [1] of Gender Selection, which offers a theoretically interesting approach to influencing gender - whether you have a boy or girl - that is non-invasive and that does not require dietary modifications.