What to do if period 1 week late, negative pregnancy test?

? Perimenopausal: Most likely you are perimenopausal, wherein the periods start becoming irregular, you may skip cycles as well. Perimenopause is the phase in a woman's life prior to menopause, when the periods completely stop.

See if any of these: apply. Reasons for missed /late periods: low body weight, obesity, marked weight gain or loss, over-exercise such as in endurance athletes, breast-feeding, stress, illness, eating disorders (bulimia or anorexia), travel, hormone irregularities, drug use, medications (i.e., birth control) or med problem (polycystic ovary syndrome or Asherman’s syndrome. #1 reason is pregnancy.