In the human female, elevated prolactin levels lead to lower estrogen and progesterone levels.

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Testosterone goes down for some women after the delivery, and breast-feeding releases the hormone prolactin, which inhibits arousal.

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The initial Risperdal labeling, he says, downplayed the risk of adverse events resulting from increased prolactin levels and failed to suggest that a test should be used as well.

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These hormones include cortisol (which is related to stress), estradiol (the main female sex hormone) and prolactin (which, as its name suggests, triggers her breast tissue to develop the ability to secrete milk).

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The men in these couples, she discovered, exhibited significant changes in their levels of cortisol, testosterone (the principal male sex hormone, and thus in some sense the masculine equivalent of estradiol) and prolactin over the courses of their partners' pregnancies.

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