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Date of last update: 10/14/2017.

Forum Name: Obstetrics

Question: Confused on due date, conception, and LMP

 jb12345 - Tue Nov 03, 2009 9:38 pm

My girlfriend a I recently found out we were pregnant. She took a e.p.t. test and that was positive so two days later she went to the doctor for i guess what would be the official test and she was tested positive and given a due date of June 29th 2010.

i was excited to know and went online and looked at all kinds of stuff, i was playing around on all the calculators and when i would type the due date in it would say the most likely tome of conception was oct. 2 to oct 6, well i travel alot for work and the last time we had intercourse before finding out about being pregnant was sept. 19 and sept. 20, 2009. all that raised a red flag to me, i was wanting to know is it possible that i am not the father of this child based on the information i have given you?

i have not said anything to her because i have no idea about how a womans body works nor anything about child berth....i am really seeking a professional help on this because i am really worried.

Thank you
 Debbie Miller, RN - Tue Nov 10, 2009 9:19 pm

User avatar Hello,
It would be impossible to say at this point because all women do not ovulate at the usual time. There are wide variations and we just take 14 as an average day of the cycle for ovulation. This is how due dates are calculated and day 14 is determined by her menstrual period. Was she on her period at the time you had intercourse?

Estimates are somewhat inaccurate and she may get another date based on an ultrasound exam. These are often more accurate when done fairly early in the pregnancy. The only sure way to know is with a paternity test after the birth of the baby.

Do you have questions about her fidelity other than this date in question? Perhaps you just need to talk about it. Show interest in the pregnancy and share the online sites you were exploring. Tell her you wondered about the dates and ask what she thinks about it. I would ask her when the last menstrual period was, which is usually used to calculate due date. This might help to open the door to conversation. Trust is an important element in a relationship.

Best wishes.

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