is progesterone hormone.It is used for the maintenance of early pregnancy
(up to 12th week only) in cases of documented history of repeated miscarriages due to luteal phase defect. In other words there should have been repeated miscarriages in the past and there should be documented luteal phase defect (i.e. progesterone deficiency
Your doctor must have detected progesterone deficiency in your wife and that's why it has been given ,since there is past history of repeated miscarriages.
GO ahead with it.
helps in protecting fetus from developing neural tube defects.
Carry on with this.