Duration of the act of intercourse is not vital, rather deposition of semen, fertility period of menstrual cycle, and ability of conception matters the most. Using protection is helpful in avoiding conception, but not 100% guaranteed method.
Disclaimer - The content is not intended to be as a substitute for a
professional medical advice, diagnosis, or treatment. Always seek
the advice of your physician or other qualified health provider
with any question you may have regarding your medical condition.
Never disregard professional medical advice or delay in seeking
it because of something you have read on the website.