The phenomenon of male lactation in humans has become more common in recent years due to the use of medications that stimulate a human male's mammary glands.
It is also possible for males (and females) to induce lactation through constant massage and simulated 'sucking' of the nipple over a long period of time (months).
Male Pregnancy Now an Option, Beijing Surgeon Says:
Doctor Chen Huanran is looking for a few good men -- to get pregnant. The Beijing doctor, one of China's most-prominent sex change surgeons. says he has developed the technology to impregnate a man, and now he wants to use his technique to help his transsexual patients have children of their own. If successful, it would be the first time ever that a male human has become pregnant
http://www.china.org.cn/english/2002/May/33452.htm
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