Hi, Thanks for posting in HCM. I understand your concern. Gestrenol contains Allylestrenol , which is a synthetic progestogen used to prevent threatened miscarriage, recurrent pregnancy loss and premature labor. But, for the drug to be effective, you should have conceived, so that it would support your pregnancy. It seems that you have taken the medication on your own without proper indication, which is not correct. The issue is, since you have been having cycles little longer than usual and probably might not be ovulating at right time as required. Hence, get an ultrasound abdominal scan done first to know what would the reason for delay in periods as you have got negative pregnancy test. Kindly consult Gynecologist with the report to know the proper cause so that it could be addressed to accordingly. Hope the information provided would be helpful. All the best.