One frequent question I hear is, "Does doing a blastocyst transfer increase my chance of having a boy." Urban legend has it that there is a greater chance of a boy with a blastocyst transfer because male embryos supposedly develop more quickly than females.
Now a study published in the October 2009 edition of "Fertility and Sterility" shows that "male embryos do not grow faster than female embryos in culture. Blastocyst transfer does not result in a sex-ratio imbalance in resulting offspring." This study from Australia followed the resuts of 435 blastocyst transfers and reached the conclusion that there is no increase in male births.