I started light spotting (brown) at 5 weeks 1 day and it continued for 9 days. It stopped for 2 days and then, out of nowhere, at 6 weeks 5 days, gigantic huge gushes of bright red blood. Lots and lots of it. Enough for a pad, as well as cramping. I thought for sure my pregnancy was ending. I called my husband to come home from work. He drove me to my perinatologist where they did an ultrasound. The ultrasound showed a well formed gestational sac, a fetal pole, and a strong heartbeat. No ectopic, no molar, no blighted ovum. Everything looks normal. I had been taking lovenox for a protein S deficiency with factor V mutation. After 5 days of spotting, my perinatologist took me off of Lovenox indefinitely. She says that we're not out of the woods right yet. She says that if I can keep this in until 8 weeks, she'll feel a lot better. She didn't find a subchorionic hematoma, nor did she find a placental abruption, she says that anything else she doesn't care about. She says she doesn't know what's causing the bleeding, but has me on activity restriction (no exercise, no running, no yoga,) pelvic rest, and flight restriction. I'm nervous, to say the least. I'm still bleeding too, but the blood is mostly brown now.
I have been searching all over the internet and in books to find out what causes intense bleeding in early pregnancy when there are no apparent problems. There does not seem to be any answers out there. Does anyone know why someone would possibly bleed?