Anyone know what these little red spots on my face are???

For the last two months right before my period my face breaks out into small red spots all over my face. I have never had problems with my skin breaking out before. I am a 39 yr old female. They don't itch at all and are only on my face. They only last a few days and then disappear again--until my next period. This pms symptom seems to have come out of nowhere as I have never had it before. I looked up acne but the spots don't resemble or fit the description of any type of acne (and besides they completely disappear in a few days). Wondering if anyone has this happen and is there a term for it? Is it related to hormonal shifts? The spots are not pus filled nor do they itch--they just mysteriously appear and then disappear?