<qa>  What is the name of the arm that will be administered in the IBSA?If the donor meets the inclusion criteria, she will be informed of the study and, if she agrees, she will sign the informed consent. Randomization shall be performed in 2 arms; arm 1 will be administered subcutaneous progesterone 25 mgday Prolutex; Angelini, Spain, and arm 2, intramuscular progesterone 50 mgday Prontogest IBSA, Italy. In each arm 12 donors ITT population will be included. 