Erotic lactation

Erotic lactation is sexual arousal by breastfeeding on a female's breast. Depending on the context, the practice can also be referred to as adult suckling, adult nursing, and adult breastfeeding. Practitioners sometimes refer to themselves as being in an adult nursing relationship (ANR). Two persons in an exclusive relationship can be called a nursing couple.

"Milk fetishism" and "lactophilia" are medical, diagnostic terms for paraphilias and are used for disorders according to the precise criteria of ICD-10 and DSM-IV.

Breasts, and especially nipples, are highly erogenous zones, for both men and women. Nipple and breast stimulation of women are a near-universal aspect of human sexuality, though nipples in males are not as sexualized. Humans are the only primates whose females have permanently enlarged breasts after the onset of puberty; the breasts of other primate species are enlarged only during pregnancy and nursing. One hypothesis postulates that the breasts grew as a frontal counterpart to the buttocks when primates became upright, thus attracting males, a theory first developed in 1967. Other theories include that by chance breasts act as a cushion for infant heads, are a signal of fertility, or elevate the infant's head in breastfeeding to prevent suffocation. Paradoxically, there is even a school that believes that they are an evolutionary flaw, and can actually suffocate a nursing infant. The association of pleasure and nutrition holds true as well for the lips, also erogenous zones, where pleasure may have led to "kiss feeding", in which mothers chew food before passing it on to the child.

Unintended milk flow (galactorrhea) is often caused by nipple stimulation and it is possible to reach normal milk production exclusively by suckling on the breast. Nipple stimulation of any sort is noted in reducing the incidence of breast cancer.

Some women lose the ability to be aroused while breastfeeding, and thus would not find lactation with a sexual partner to be erotic. This can be a result of physical reasons (soreness) or psychological reasons (conflicted about her breasts being used other than for an infant).

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Wikipedia