while I haven't noticed it, I've been told it's quite common, and tends to start sometime after about 10-11 weeks...so you're right at the time to expect it. The Mayo Clinic book says it has something to do with the increased fluids in our body also build up in your eye, and your cornea thickens, which makes vision blury. But it should be temporary and go away after the baby is born, and the book does not recommend getting a new prescription during pregnancy. I've been wondering If I'm going to start having eye trouble soon...