It is possible to get pregnant two days before your period is due if it is delayed by twenty days.

Patient's question:

Sure, here is the translation of the content you provided:
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No
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Doctor's answer:

In the exclusion of pregnancy, there are mainly two reasons: 1. Neuroendocrine dysfunction; 2. Organic lesions or drug-induced causes. Additionally, excessive mental stress, environmental changes, malnutrition, and other issues can also lead to irregular menstruation.