Red spotting in late pregnancy??

Nicole • Mummy of 3💙💙💗 #4 due October💗
I'm getting really annoyed. Im 34 weeks 3 days and I'm spotting red blood again for about the 5th time in the last 3 weeks. The first time it happened I called the midwife unit and they said if I have no pain all is fine. But I don't see how red blood can be fine. Especially if it's happening this many times. Does anyone know what could be causing this? If I call them again they are just going to say the same so I'll just mention it to my consultant tomorrow, but I just want to know what this could mean?