An article from the New York Times opines that there is no reliable gender test.
Link:
http://www.nytimes.com/2008/08/03/o...&bl&ei=5087&en=8cf38e35a8549324&ex=1217908800
Link:
http://www.nytimes.com/2008/08/03/o...&bl&ei=5087&en=8cf38e35a8549324&ex=1217908800