Progesterone was a steroid hormone involved in the female menstrual cycle, pregnancy and embryogenesis of humanoids and other species. In 2372, Doctor Julian Bashir stimulated Kira Nerys' estrogen and progesterone production to enable a Human baby that she was forced to carry, to metabolize Bajoran nutrients. (DS9: "Body Parts") Makara herbs were typically used by Bajoran women to increase their progesterone levels when pregnant. (DS9: "The Darkness and the Light")