Can primolut N cause heavier than normal periods ? My mother was prescribed Primolut N for 21 days for disordered proliferative endometrium due to hormonal imbalance. After stopping the medicine she got periods after 4 days and from the second day of period she started passing clots frequently with abdominal pain and discomfort. Just want to know if this is side effects of medicine or something else ? We did endometrium biopsy and Hysteroscopy and nothing was found. Really worried as she is 50 and hasn't got menopause yet.