Pregnancy Due Date Calculation: Understanding Your Conception Timeline

Question
first day of period was january 29th.  when would the baby be due? original due date was October 26th.

Answer
The due date of Oct. 26th does not correlate with the date of the last period you provided.  Based on the first day of the last period, the due date would have been Nov. 5th with an estimated conception date of around Feb. 12th.  However, as sperm can live in the reproductive tract for up to 5 days, then intercourse in the 5 days prior to this could also have resulted in the pregnancy.