
How To Determine The Paternity Of The Fetus?

Question: Is it possible to determine paternity if sex with 2 guys was within 10 days and there are 2 early ultrasound results?
Brief Answer:
Please provide additional information
Detailed Answer:
Please provide the following details:
1. The dates of each ultrasound and exactly how far along you were at each scan
2. Your due date
3. The exact dates of intercourse with each guy
4. Mention whether there were condoms, ejaculation or any other information
Awaiting..
Dr. Tim
Please provide additional information
Detailed Answer:
Please provide the following details:
1. The dates of each ultrasound and exactly how far along you were at each scan
2. Your due date
3. The exact dates of intercourse with each guy
4. Mention whether there were condoms, ejaculation or any other information
Awaiting..
Dr. Tim
Above answer was peer-reviewed by :
Dr. Arnab Banerjee


XXXXXXX 12 was first day of last period. Sex with guy 1 was day 8 of cycle. No inside ejaculation. Sex with guy 2 was day 17 of cycle. There was inside ejaculation. Cycles are regular between 28 and 30 days. Ultrasound 1 done 2/25 showed 5 weeks 5 days. Ultrasound 2 done 3/1 showed 8 weeks 3 days.
Hello are you there?
Hello are you there?
Brief Answer:
Please confirm the facts, perhaps double check the dates because not all of them are making sense
Detailed Answer:
So here are the facts:
1. LMP = 1/12, his would give a due date of 10/19, conception = 1/26
2. Ultrasound 2/25 = 5 5/7wk, due date of 10/23, conception 1/30
3. Ultrasound 3/1 = 8 3/7 wks, due date of 10/8, conception 1/15
4. Guy1 = day 8 of cycle (1/19), no ejaculation
5. Guy2 = day 17 of cycle (1/28), ejaculation
Please check my dates on the dates of intercourse because we might be counting the cycle differently. I find it very confusing that the two ultrasound disagree by as much as they do - this does not make sense. Please double check how I have listed things here and confirm or correct.
Let me know accordingly.
Dr. Tim
Please confirm the facts, perhaps double check the dates because not all of them are making sense
Detailed Answer:
So here are the facts:
1. LMP = 1/12, his would give a due date of 10/19, conception = 1/26
2. Ultrasound 2/25 = 5 5/7wk, due date of 10/23, conception 1/30
3. Ultrasound 3/1 = 8 3/7 wks, due date of 10/8, conception 1/15
4. Guy1 = day 8 of cycle (1/19), no ejaculation
5. Guy2 = day 17 of cycle (1/28), ejaculation
Please check my dates on the dates of intercourse because we might be counting the cycle differently. I find it very confusing that the two ultrasound disagree by as much as they do - this does not make sense. Please double check how I have listed things here and confirm or correct.
Let me know accordingly.
Dr. Tim
Above answer was peer-reviewed by :
Dr. Arnab Banerjee


I am so sorry. The second ultrasound was done march 1 and dated pregnancy at 6 weeks 3 days not 8 weeks 3 days. Thanks for catching that and I look forward to your answer.
Hello are you there?
Will someone please answer. It has been over 11 hours.
Hello are you there?
Will someone please answer. It has been over 11 hours.
Brief Answer:
Guy#2 seems the father based on the information that you gave
Detailed Answer:
Sorry about the delay. So here are the new facts:
1. LMP = 1/12, his would give a due date of 10/19, conception = 1/26
2. Ultrasound 2/25 = 5 5/7wk, due date of 10/23, conception 1/30
3. Ultrasound 3/1 = 6 3/7 wks, due date of 10/2, conception 1/ 29
4. Guy1 = day 8 of cycle (1/19), no ejaculation
5. Guy2 = day 17 of cycle (1/28), ejaculation
So the LMP AND both ultrasounds support conception in late January. The LMP is NOT as accurate as the ultrasounds. The most accurate ultrasound is the first one (and the second one agrees almost perfectly with it). The 'window' within which conception occurred, thus, is 1/27-2/2. This completely rules out Guy1. Guy2 seems the father in this case.
I hope this helps
Dr. Tim
Guy#2 seems the father based on the information that you gave
Detailed Answer:
Sorry about the delay. So here are the new facts:
1. LMP = 1/12, his would give a due date of 10/19, conception = 1/26
2. Ultrasound 2/25 = 5 5/7wk, due date of 10/23, conception 1/30
3. Ultrasound 3/1 = 6 3/7 wks, due date of 10/2, conception 1/ 29
4. Guy1 = day 8 of cycle (1/19), no ejaculation
5. Guy2 = day 17 of cycle (1/28), ejaculation
So the LMP AND both ultrasounds support conception in late January. The LMP is NOT as accurate as the ultrasounds. The most accurate ultrasound is the first one (and the second one agrees almost perfectly with it). The 'window' within which conception occurred, thus, is 1/27-2/2. This completely rules out Guy1. Guy2 seems the father in this case.
I hope this helps
Dr. Tim
Above answer was peer-reviewed by :
Dr. Arnab Banerjee


Thank you. When you say "completely rules out guy1," does that mean there's 0% chance? Should I do a third ultrasound to see if theres three matching ultrasounds? I'm very stressed about this and I need some resssurance so I appreciate your understanding in advance.
Brief Answer:
No one will commit to 100%
Detailed Answer:
Hi again,
Given that Guy1 was a full 8 days prior to the 'window' of conception which is based on your LMP AND two ultrasounds AND you state that he did not ejaculate - and you are 100% certain, without a doubt, that he did NOT ejaculate, then he is 100% not the father of the baby.
Dr. Tim
No one will commit to 100%
Detailed Answer:
Hi again,
Given that Guy1 was a full 8 days prior to the 'window' of conception which is based on your LMP AND two ultrasounds AND you state that he did not ejaculate - and you are 100% certain, without a doubt, that he did NOT ejaculate, then he is 100% not the father of the baby.
Dr. Tim
Above answer was peer-reviewed by :
Dr. Arnab Banerjee

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