Thank you for your question.
I am Dr Saha, I shall try my best to help you.
As the tubes were tied, the risk of pregnancy is unlikely.
Apart from pregnancy there are other causes of missed or delayed periods.
Hormonal dysfunctions can be possible.
Excessive physical activity sometimes can be a factor.
Thyroid hormone abnormalities can cause it.
Sudden weight loss or gain, stress, anxiety can be factors.
Generalized illness, infection can be possible.
Sometimes cause may not be detected too.
You can wait & watch.
If you develop any other symptom or do not get period in next 1-2 cycles, please consult a gynecologist.
I hope this information helps.
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