Yes, you can use Wellsprings Serenity and Wellsprings 20-1 together if you need only a small amount of oestrogen.
Both creams have the same progesterone content so it is advisable if you wish to use both not to apply at the same time or on the same part of the body. We suggest you alternate between them with each dose.
Use the 20-1 cream when symptoms are most severe, either morning or evening, and use Serenity for the other dosage of the day.