Many studies in the last 45 years have shown that women prefer a boy to a girl for their first-born child, suggesting that this preference is universal in Western societies. A careful examination of these studies reveals, however, that the subjects were often women who were not pregnant and/or students. A review of sixteen studies with first-time-pregnant women showed that in most cases the opposite was true, namely, that a girl was desired more often than a boy, especially during the last two decades (from 1981 to 1996). Data concerning expectant fathers, however, indicate that they prefer a boy rather than a girl. A preference for a boy first was also observe for both non-expectant males and females. Women’s preference for a male child decreased and men’s preference increased slightly when the two sub-periods (before 1980 vs after 1981) were compared. A difference between men and women is, however, evident whatever the sub-period: men more often prefer a boy than women. These findings suggest that something specific about being pregnant is related to the preference for a girl first.