Probably just price. Delestrogen is Estradiol Valerate. Estradiol Valerate is what Sandoz lists in its U.S. Catalog. But, I would suggest that you bypass pharmaceutical companies of all types and use compounding pharmacies (they make their own estradiol valerate.) They tend to sell and ship for less than you can get the others at a regular pharmacy.
You may want to google compounding pharmacies and get a web list. If you find one in your area you can forget the shipping charges that web resources will probably require you to pay.
