Raynaud's or Vasospasm is when blood moves away from the nipples. Blood vessels tighten and go into spasm and blood doesn't flow properly. It is usually associated with nipple colour change to white or purple.
There are two main causes of nipple vasospasm.
Nipple trauma - if a baby isn't latched well. Correctly the latch can correct this issue.
Vasospasm that occurs at random times not related to breastfeeds is more likely to be a condition related to Raynaud’s, where a person experiences similar symptoms in fingers, toes, etc in response to exposure to cold.
Try these tips to help:
Massage warmed olive oil into nipples post feeds
Vit B6 Supplements - 100mg B6 twice a day
Magnesium - 250-300mg twice a day
If you need more help contact me here.