1. Workouts: Muscles under the breasts can cause discomfort and give her pains after a serious weight-lifting routine or excessive push-ups.
2. Menstruation: When your woman is menstruating, this hormonal change can cause pain in her breasts, the swelling and tenderness a day before the period begins is a source for concern.
3. Fibrocystic Breast Tissue: for women with this tissue, intake of too much caffeine can give discomfort.
4. Uneven Breast Tissues or Lumpy Breasts: This does not mean she has or is prone to cancer, it just means she is more sensitive to hormonal changes.
5. Too Tight Bra: If this is the case or her cup's just too small, then the pain cause by the underwire pushing against the breasts.
6. If she overstretches the muscles under her breast tissues by lifting too heavy loads or pulling at tough things then the pain is sure to come.
7. For those with HUGE boobs, if they do not have the proper support for the breasts while exercising, then the jumping about of the boobs can cause pains.
8. Those who are the extra-larges in the breast department are prone to back pain which is cause by the strain the breasts puts on their back, and you pulling at it might not be helping.
9. She Just Doesn't want You to: It might be that she doesn't like you, she's not in the mood or doesn't enjoy it with you... whichever's the reason, your touch is not welcomed.
10: Understand when she's complaining and help her get comfortable with you, so, the fondling will not be all about you, but you both.