Abstract: Provided are enhancing transdermal absorption compositions useful in transdermal absorption of progestins including progesterone and optionally an estrogen for contraceptive or hormone replacement and dosage forms using the novel enhancing compositions. The enhancing compositions comprise a combination of a lower alkyl ester of a polycarboxylic acid, an aliphatic monohydroxy alcohol and an aliphatic diol. Also provided are processes of administration of progestins and optionally estrogens using the novel dosage forms.