Hello, I would be happy to help you with your question.
1. Based on a due date of 10/30
2. This would correlate in most cases with a last menstrual period of about 1/24
3. This would correlate with conception of 2/7 +/- 5 days
4. This correlates with intercourse on 2/12 leading to a conception
5. There is variation in timing of conception and implantation
that leads to confusion in the actual dates
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