http://pregnancy.about.com/od/genderselection/Sex_Selection_How_to_choose_a_girl_or_boy_for_your_next_baby.htm
how to have a boy..how to have a girl..
from a cursory reading, MORE sex, seems to favor having a girl..and invoilves sweets & chocolate
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and the more science-y article
http://www.science20.com/news_releases/chromosomes_are_so_20th_century_male_genes_really_determine_baby_gender_says_study
Chromosomes Are So 20th Century - Male Genes Really Determine Baby Gender, Says Study
By News Staff | December 14th 2008 01:00 AM | Print | E-mail | Track
Men determine the sex of a baby depending on whether their sperm is carrying an X or Y chromosome. An X chromosome combines with the mother's X chromosome to make a baby girl (XX) and a Y chromosome will combine with the mother's to make a boy (XY).
A Newcastle University study suggests that an as-yet undiscovered gene controls whether a man's sperm contains more X or more Y chromosomes, which affects the sex of his children. On a larger scale, the number of men with more X sperm compared to the number of men with more Y sperm affects the sex ratio of children born each year
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