This might be a daft question (in which case forgive me - pregnancy paranoia) - but I have some time off tomorrow and really fancy a dip in Hampstead Ladies Pond. I'm 10 wks pregnant. Is there any reason to avoid this. My worries are 1) infection (the water is reasonably clean - although not compared to a chlorinated pool) 2) cold temperature having a negative effect on the baby. Any thoughts?