Elarwood- Nurse at clinic seems to think it might be mild OHSS and I'm going in tomorrow for a blood test to investigate. She said because I had 10 follicles I was at risk and told me to keep my fluids up. The only good thing I have read is that late onset can be a sign of BFP because the HCG sets it off. Fingers crossed & fingers crossed for your beta tomorrow! X. Dh won't let me POAS before beta grrr