What are all possible reasons for a missed period?

Please make an appt : To see your gyn , so your gyn can explain that to you, #1 reason if u are sexually active is pregnancy - normal or abnormal, also could be due to hormone imbalance and other problems , your gyn can do an evaluation and then rec something to start your perios.

Here are some: Reasons for missed/late periods: low body weight, obesity, marked weight ^ or v, over-exercise, endurance athletics, breast-feeding, ^ stress, illness, eating disorders (bulimia or anorexia), anovulatory cycle (no egg released), travel, hormone irregularities, drug use, meds (i.e., birth control) or medical problems (i.e. PCOS). #1 reason is pregnancy.