Hello dr. My sister(unmarried) is 26 yr old,5 8 height,60kg weight. Her menstural cycle is of 28-30 days but has very light bleeding ,sometimes with clots,sometimes brownish in colour. It remains only for 2 days. She has severe cramp in lower abdomen in the 1st day,sometime gets fever . Is this a serious problem? Dr said light bleeding is normal. Will it affect her fertility? Is there any treatment she needed?