Can you determine your baby's sex by the sexual position? Can you predict it by how you are carrying?
The facts are that these notions are not true. The sex of your baby is determined by the father; more specifically, if sperm carrying an X-chromosome fertilizes the egg, the baby will be a girl and if the sperm carrying a Y-chromosome fertilizes the egg, a boy will result. The sex position has no clear effect on which type of sperm (X or Y) successfully fertilizes the egg.
In addition, the baby's size and position determine how one "carries" their baby. For example, during late pregnancy, the baby's head "drops" lower into the pelvis in preparation for delivery; that will make it seem that the mother is carrying "low," but that happens for male and female babies. A mother-to-be may be "carrying high" simply because the baby is large, not because of the gender.