Here's one possibility (taken from breastfeedingmomsunite.com):
Many people haven’t ever heard of Raynaud’s phenomenon. This condition usually affects women from about 20 to 50 years of age. For some women, Raynaud’s affects the nipple whether or not she may be pregnant or breastfeeding. This is a situation where there is an abnormal spasm of arteries supplying blood to the fingers or toes, closing off blood supply and causing numbness, burning, tingling, pain- sometimes very intense pain and a temporary loss of color (blanching, pallor, waxy white). The skin of the affected area can also turn blue from lack of oxygen. When the circulation returns, there is sometimes a temporary flushing before returning to normal. The normal skin color goes from white to red, or raspberry to normal, or white to blue to red, or raspberry to normal.
It is this biphasic or triphasic color change that helps in the unique diagnosis of Raynaud’s. The triggers which usually set off the vasospasm are cold or rapid temperature changes and sometimes emotional stress. At a conference, I heard of a family of women that never wanted to swim because of the painful blanching of their nipples. The poor young ladies thought this happened to all women and didn’t understand how other girls could stand it for swimming!
Raynaud’s of the nipple in breastfeeding women is usually described as excruciating nipple and breast pain after nursing, pumping /expressing milk and at other times when the nipple is cold or wet. It is always associated with the biphasic or triphasic color change. Sometimes the areola can also change shape while this is happening. Not all women who experience nipple blanching and pain have Raynaud’s phenomenon. However it can be misdiagnosed as nipple vasospasm for other problems such as poor latch or confused with pain from yeast or Candida albicans infections. It can also happen simultaneously with other breastfeeding problems. It is always important to get evaluated by your medical provider or Lactation professional.
