The human embryo is formed at conception after the sperm penetrates the ovum or egg. This process naturally occurs in the fallopian tube, but recently with the advent of advanced reproductive technologies, fertilization may occur in-vitro or outside the human body.
The genetic make-up of the fetus is therefore determined at the time of conception by the genetic material presented by the sperm and the ovum. A female carries two ”X” chromosomes while the male carries an “X” and a “Y” chromosome. A sperm carrying an “X” chromosome results in a female fetus whereas a sperm carrying a “Y” chromosome will result in a male embryo.
Many attempts have been made to choose the sex of an incoming infant before it is born, including changes in diet, timing of sexual intercourse, changing the vaginal environment and genetic engineering.
Theoretically because the “X” chromosome is larger and denser it is believed that sperms that carry the “X” chromosome are heavier, slower, but more resilient to harsh environment, such as an environment that is acidic.
Based on the theory described above, multiple attempts have been made to determine if it is feasible to time intercourse around the time of ovulation. The theory being that the faster moving sperm (“Y” carrying sperm) would be more likely to fertilize the egg. Therefore couples who desire to have a masculine child are advised to have intercourse at the time of ovulation or shortly after that to increase the odds of the fast moving sperm to make it to the egg before it decays. Whereas those preferring a female offspring are advised to have intercourse hours or days before ovulation thereby allowing the less resilient “Y” bearing sperms to die and improving the odds of X-bearing sperm to survive and achieve fertilization.
Others theorized that acidifying the vaginal PH will kill the fragile Y carrying sperm and thereby allowing survival of the X-carrying chromosomes. Yeast infections, the Atkins diet or any type of food that increases the vaginal acidity were recommended to those who desired a girl whereas yogurts, bicarbonate douching or any diet that decreases vaginal acidity have been recommended to those who desired a male offspring.
Although in theory the above-mentioned dietary and environmental manipulations make sense, in reality none of them have been shown to be effective. To date there is no clear association between the type of diet, timing of intercourse, manipulating position or the environments in the vagina to preferentially determine the sex of the conceptus.
For more information, please call Dr. Navizadeh at 661-290-3337.