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How To Determine The Date Of Conception?
Question: If I had my period on March 10th, and had unprotected sex every weekend after, with the last encounter being the 31rst, in which he didn't ejaculate and I took morning after pill 8 hrs later, then I took an at home pregnancy test on April 5th and was positive, and then on April 18th had a dating ultrasound which dated me at 5 weeks and 4 days. What is the likelihood it was the march 31rst encounter?!
Brief Answer:
Thank you for using HCM, I would love to help
Detailed Answer:
if the ultrasound on the 18th said that you were 5 4/7 weeks, and the last period started 3/10, then you almost certainly got pregnant on the weekend of 3/20-23. that is because the sonogram dates you to the last menstrual period, and the conception is typically 1 1/2 to 2 weeks later.
I hope this helps, please let me know if you have any more questions.
Thank you for using HCM, I would love to help
Detailed Answer:
if the ultrasound on the 18th said that you were 5 4/7 weeks, and the last period started 3/10, then you almost certainly got pregnant on the weekend of 3/20-23. that is because the sonogram dates you to the last menstrual period, and the conception is typically 1 1/2 to 2 weeks later.
I hope this helps, please let me know if you have any more questions.
Above answer was peer-reviewed by :
Dr. Yogesh D
But it also couldn't be Mach 31rst, bc I took morning after pill, and i had a positive test 5 days later
Could you just also explain in mor detail why it wasn't the 31rst?!
Could you just also explain in mor detail why it wasn't the 31rst?!
Brief Answer:
Sure, I will explain in detail
Detailed Answer:
pregnancies are dated from the first day of your last period, not from the date of conception. I know that this is confusing to people, but that is how doctors date pregnancies. therefore, when the ultrasound said you were 5 weeks and 4 days, that means that the pregnancy was consistent with a last period of March 10, which is exactly when you said your last period took place.
this means that both based on your period and based on the ultrasound, you were 5 4/7 weeks on April 18. that is the best evidence a doctor could have for accurate dating, and is as close to 100%certain as you can get.
therefore, you were already pregnant on the 31st, and could not have conceived that day. the pills you took eight hours later didn't effect the pregnancy at all, because it was over a week past the conception which really occurred the weekend of the 20-23 of March. that is long past the 72 hour window within which the morning after pill can work.
based on the information you have me, this is as solid as you can get, you did not get pregnant on the 31st.
let me know if you have any more questions, or if you still have difficulty understanding my explanation.
Sure, I will explain in detail
Detailed Answer:
pregnancies are dated from the first day of your last period, not from the date of conception. I know that this is confusing to people, but that is how doctors date pregnancies. therefore, when the ultrasound said you were 5 weeks and 4 days, that means that the pregnancy was consistent with a last period of March 10, which is exactly when you said your last period took place.
this means that both based on your period and based on the ultrasound, you were 5 4/7 weeks on April 18. that is the best evidence a doctor could have for accurate dating, and is as close to 100%certain as you can get.
therefore, you were already pregnant on the 31st, and could not have conceived that day. the pills you took eight hours later didn't effect the pregnancy at all, because it was over a week past the conception which really occurred the weekend of the 20-23 of March. that is long past the 72 hour window within which the morning after pill can work.
based on the information you have me, this is as solid as you can get, you did not get pregnant on the 31st.
let me know if you have any more questions, or if you still have difficulty understanding my explanation.
Above answer was peer-reviewed by :
Dr. Yogesh D
Thank you so very much. You have lessened my anxiety.
I do have a ultrasound on the 6th. That should date me at 8 weeks 2 days or so correct?!
Just don't want to stress about it anymore.
Thank you again.
I do have a ultrasound on the 6th. That should date me at 8 weeks 2 days or so correct?!
Just don't want to stress about it anymore.
Thank you again.
Brief Answer:
Sounds about right
Detailed Answer:
I 'm glad I could help relieve your anxiety. I am certain that you need no longer worry about it. good luck!
Sounds about right
Detailed Answer:
I 'm glad I could help relieve your anxiety. I am certain that you need no longer worry about it. good luck!
Note: Revert back with your gynae reports to get a clear medical analysis by our expert Gynecologic Oncologist. Click here.
Above answer was peer-reviewed by :
Dr. Yogesh D
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