Can You Trick Your Body into Letting You Pick the Sex of Your Baby?


baby with pink and blue balloons

The Trivers-Willard Hypothesis suggests that mothers who are in “better condition” will produce more sons, and those in “lesser condition” will produce more daughters.

Many people would love to choose their children's sex for a multitude of reasons, and there are some who swear by certain methods to do so. “Gender swaying” has become a popular topic of conversation for some parents and doctors alike.

There have been numerous studies done regarding its effectiveness, and there have even books written on the subject. The Trivers-Willard Hypothesis is a gender-swaying theory introduced by Robert Trivers and Dan Willard, both of Harvard, in 1973.

{ MORE: Natural Gender Swaying }

The hypothesis in its most basic form is akin to survival of the fittest. In evolutionary biology and evolutionary psychology, it suggests that mothers who are in better “condition” will produce more sons, and those in lesser “conditions” will produce more daughters as a way of carrying on their genes.

Trivers and Willard believed that if weaker mothers birthed weaker sons, these sons would have a harder time mating and producing heirs, so biochemical reactions would step in to offset that outcome and, in essence, maintain a balance in the sexes.

{ MORE: Gender Selection: What Is Your Personal pH? }

Therefore, these weaker mothers would actually produce more daughters who would have a better chance at reproducing more offspring and carrying on the “family name,” so to speak. And vice-versa, stronger mothers would produce more sons for the maximum amount of offspring. (It is noteworthy that this theory appears to hold truest in polygynous species and is reversed in polyandrous species.)


What do you think?

Can You Trick Your Body into Letting You Pick the Sex of Your Baby?

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  1. lucy says:

    Read ‘Swaying’ by Lucinda Blanchard on Amazon. It’s a fictional account of two woman who really want a daughter and try lots of crazy methods to sway the odds.


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