Female Breasts serve dual purpose for milk as well as sexual.
The female breasts work differently during sex fore play with husband and during lactation for nursing the child. When a woman nurses her baby she expects her breasts to respond and feel "different" from when her husband sexually stimulates her. She may not expect to feel "sexual" pleasure when her baby sucks the nipple. Mother who nursed their baby for at least two months, their desire for sex likely to return at a faster rate than it did for the mother who did not. Few mothers may experience sexual arousal while nursing. The let-down reflex can cause some pretty intense and sweet sensations and there is the aforementioned chemical and psycological connection between the nipples and uterus.
The sensitivity of a woman's breasts to stimulation varies considerably from one female to the next. There are female who find their breasts extremely sensitive to their own and/or a husband's touch, while others do not experience any pleasant sensations at all. Some women have more sensory nerve endings located in their nipples and breasts than others. A female's relationship with her breasts also has an influence on their perceived sensitivity. A female's menstrual cycle often influences the sensitivity of her breasts, many experience periods of breast tenderness that makes any sexual stimulation unbearable. The sensitivity of the breasts to stimulation may flip-flop during pregnancy and nursing because of physical and psychological changes a mother experiences during this time. There is no single rule that applies to all women regarding breast sensitivity.
The connection between breast stimulation, sexual arousal, and genital sensations some women experience is the result of the psychological and chemical connections mentioned above. These chemicals are released during nipple stimulation regardless of whether a teen or adult female has ever been pregnant or had nursed before. This is demonstrated by the fact that some female's breasts always produce a little bit of milk like liquid, starting at puberty. If a female engages in frequent nipple stimulation, simulating, fantasy having a newborn baby sucking at her breast, she will likely to start lactate. A female does not have to find her breasts sensitive to stimulation for this to occur. Some of the physical responses are out of the control.