Brief Answer:
Chances are less but not nil

Detailed Answer:
Hi,

Thanks for the query.

I understand the concern and you were worried about pregnancy though the penis was pulled out before ejaculation. The chances are very less to become pregnant but it cannot be completely ruled out.
There is a preejaculate that is released during intercourse by men. The preejaculate has few sperm and very very low when compared to the actual sperm ejaculate. However we should understand that it requires only one sperm to go and meet the egg and the fertilization happens.
So it is not the right method to practice to prevent pregnancy.
For now you should rely on emergency contraceptive pill and take necessary precautions in future like a condom or pill to prevent unwanted pregnancy.

Hope this is informative and useful for you.

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