According to my specialist we are all different and sometimes need a little more insulin. You have 4 hormones that act against the insulin, this might just be the case. I thought I was in trouble as I had to alter from a 1.1 ratio to a 3.1 ratio. This has settled my bg levels and I am in low single figures again without hypos. Anything can affect your bg levels. stress is a major factor, not being very well is another. Hot weather, being too cold. Everybody is different and you may be one of the many people who have to for a short time use a little more insulin. Age makes a difference too so I am told. Now I am one of the "new age" people and I don't agree that being old means you let your bg levels rise into double figures. So I keep a tight reign on mine and feel good. If you are worried contact your SDN I am sure she or he will help