Hello and welcome to Healthcare Magic. Thanks for your query. Meprate (Medroxyprogesterone acetate) is a homonal tablet often used to induce menstrual bleeding. Normally menstruation takes place in response to the levels of female hormones. When the level of a hormone called progesterone suddenly drops, menstruation occurs. Similarly, when a course of Meprate (progesterone) is given for a few days, when the level of progesterone dropd suddenly after stopping the medication, menstruation is induced. So, actually, the menstrual bleeding induced due to Meprate will occur only after stopping the medication This is called withdrawal bleeding . So, I would advise you to wait for a few days after the course of Meprate is over to expect bleeding. Now, regarding the problem of your infertility, the irregular periods indicate a hormonal imbalance in your body. This hormonal imbalance and menstrual irregularity can be due to various causes. Some of the common causes are: - Polycystic Ovarian Disease (PCOD) - this is characterised by the presence of multiple cysts in the ovary and other problems like irregular periods, obesity, unwanted facial hair and often infertility. - Dysfunctional Uterine Bleeding (DUB) - Due to systemic problems, e.g thyroid disorders, severe malnutrition, etc. I hope your thyroid problem has been brought under control since this itself can cause irregular periods. Also, if you are overweight or obese, then regular physical exercise and diet control is also important and can help in regularizing your periods. Wish you all the best. Regards, Dr. Sheeba Stephen