Are they on the vulva? It sounds like they are tiny blood blisters, they look like moles or spots but are actually pooled old blood that cannot get back out again. I had this when pregnant with my middle son and the worst one the midwives lanced it and stitched it when I had my home birth. They reoccurred a bit in this pregnancy and one popped soon after the birth but thankfully there was very little blood pooled in there, they are all gone now. I think it's caused by during pregnancy your circulation in that area can become a bit dysfunctional because there is a lot of extra weight and pressure on that area. I have read they are a cosmetic problem but not harmful or painful in most cases and after the birth they do usually go even if it takes a few weeks or months. Xx