I was using Vagifem for a while but, honestly, I just didn't like throwing 2-3 blue plastic applicators out every week; imagine the mountain of blue after 5,10,20,30... years of the stuff. So I swopped to Estring, which is one silicone (I think) ring to ditch every three months. As far as I'm aware, from the research I've read, both are equally effective in terms of treating VA and neither have an effect on endometrial lining buildup as they both act locally, and I would hazard a guess that Estring might be cheaper for the NHS. So why do GPs prescribe and women use Vagifem rather than Estring? The ring delivers 7.5mcg of oestradiol per day, so about 50mcg per week, which GPs may feel is too high, but many women are using more than the two Vagifem usually prescribed and Estring has not been shown to have a worse effect on the endometrium than two Vagifem a week.