How To Determine The Conception Date?

Posted on Thu, 15 May 2014

Question: If I had my period on March 10th, and had unprotected sex every weekend after that the last encounter being on the 31rst of march. On that encounter he didn't orgasm and I took the morning after pill 8 hrs later. On April 5th 5 days after the last encounter I took a at home pregnancy test and was positive. On April 18th I had a dating ultrasound and they measured me at 5 weeks 4 days. What is the probability of the march 31rst encounter being the one I got pregnant?!

Answered by Dr. Dr. Soumen Patra (1 hour later)

Brief Answer:
YOU CAN'T BE PREGNANT FROM 31st MARCH ENCOUNTER.

Detailed Answer:
Hello,

Thanks for writing to us.

First of all, if you did unprotected sex every weekend including your fertile days or ovulation day (2 weeks prior to period due date), then you can be pregnant from earlier sexual intercourse.

Secondly, you have very RARE possibility of pregnancy from unprotected sex on 31st March as your last sexual encounter was in SAFE Period. Also, he DIDN'T have orgasm and you took morning after pill 8 hrs later.

Lastly, your ultrasound scan on 18th April showed gestational age 5 weeks 4 days which corresponds with your last menstrual period date (10th March) and you became pregnant within your fertile days.

Hope, this information is quite helpful to you. Kindly, close the discussion if you don't have any other query.

Wish your good health and take care yourself.

Regards,
Dr Soumen

For future query, you can directly approach me through

http://doctor.healthcaremagic.com/Funnel?page=askDoctorDirectly&docId=63326

Above answer was peer-reviewed by : Dr. Vaishalee Punj

Follow up: Dr. Dr. Soumen Patra (20 minutes later)

WhAt percentage would you say it wasn't the march 31rst encounter?!?

Answered by Dr. Dr. Soumen Patra (43 minutes later)

Brief Answer:
NO CHANCE OF BEING PREGNANT ON 31st MARCH.

Detailed Answer:
Hello,

Thanks for follow up query.

Pregnancy depends on ovulation time or fertile days and unprotected sex with ejaculation inside vagina.

31st March was NOT your fertile day or ovulation day according to last period date. Therefore, your chance of pregnancy on 31st March is EXTREMELY RARE or NEGLIGIBLE.

Pregnancy test gives positive result 10 to 14 days after ovulation and NOT before that. You CAN'T get positive result 5 days after last sexual encounter (on 31st March).

Hope, I have cleared your doubt. Kindly, close the discussion.

Good luck and all the best.

Regards,
Dr Soumen

Above answer was peer-reviewed by : Dr. Yogesh D