My girlfriend on the date not comining menstresion after chek the pregnancy test 3 time but negative now almost 2 month but menstration not com?

Get med eval. 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.

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Not pregnant. If the pregnancy test stays negative, then she is not pregnant. If she does not have a period, she probably has not ovulated. If that is not normal for her, she should see her doctor.