Hi and thanks for the query,
the commonest cause of prolonged or missed periods in a female of reproductive age is a pregnancy
. At times, depending on the test you use, there could be false negatives. It is at times encouraged to be very sure to carry out a blood test
, which entails blood measurment of beta HCG, a pregnancy hormone.
However, the fact that you are on pills, especially if you take them correctly would also minimize the chances of this being a pregnancy. Pills are hormones and it is not unusual to have some cycle derangement when one is on a contraceptive
pill. However, if this is the first time you are experiencing this, it is reasonable to do a good blood pregnancy test and / or obstetric ultrasound
to visualize the womb depending on the case.
Your primary care
physician could be of great help.
Thanks and hope this helps as I wish you the best of health.