Didn't Mr. Alpert mention something during Juliet's interview to the effect of " is it true you were able to make a male mouse pregnant?" and Juliet replied that the mouse didn't carry to term. Maybe the island is an equal-opportunity impregnator - conception for everyone! "Go ahead... get a shot... it's a vaccine, yeah, yeah.... a vaccine! I'm sure it won't make you pregnant or anything."

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