Brief Answer:
Oral sex is not the cause

Detailed Answer:
Hello and Welcome

I appreciate your concern

Oral sex cannot cause pregnancy. Irregular period or periods can be due to a number of factors including stress,weight gain, polycystic ovaries etc. A single out of time period may regularize by itself. You dont even need to take a pregnancy test if no penetrative vaginal sex took place. If the irregular periods persist then a gynecologist should be consulted for further evaluation

Wishing you best of health

Thanks

Please consult your doctor before deciding on any further course of action.

For future follow up / correspondence you may ask me directly at the link given below

http://doctor.healthcaremagic.com/Funnel?page=askDoctorDirectly&docId=68107

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Brief Answer:
Yes, its possible with medication

Detailed Answer:
Hello

The antibiotics could have contributed towards the irregular period as can many other medications.

Wishing you best of health

Thanks

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Brief Answer:
Most welcome

Detailed Answer:
You are most welcome.

Hope I have answered your query.
If you have any further questions I will be happy to help If you do not have any clarifications, you can close the discussion and rate the answer.

Wish you good health.

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