Is there an accurate way to date conception?


Q: My lover is pregnant. Her LMP was June 4th. She has had her 2nd ultrasound today. The EDD is 11th March, but based on the LMP. Her cycle has always been a little irregular (completely in fact until the April, May and June). We had sex but used a withdrawal method, although I did ejaculate on the surface of her vagina, on 27th June. Please don't judge, but she is married and had unprotected sex around 18th June - which fits the 'standard' ovulation date. What chance - I realise it may not have a % but 'approximately' - is it that the baby was conceived in 27th June, given the 'withdrawal' method and the distance from the 'standard'. I do want this to be my baby as does she, but we both feel it isn't. The nurse at the 2nd ultrasound (today) said that the embryo was larger than 'expected' and growing well - I'm not sure if that lends itself to an earlier conception date or not, or, as I am western and she (and her husband) are Asian, this might make it more likely to be mine. I know no-one can 'guarantee' either way without testing but I have read some forums/used some calculators that seem to show it's an minutely small chance of being mine, but others have said you can conceive at any point...

Symptoms:  pregnancy

A:   This question is currently in queue and will be answered shortly by one of our doctors. In the meantime you may browse our library of answered questions by clicking here.

Related Q&A

Q: Is it possible for me to be pregnant? Are these signs? Is it too early to tell? I had unprotected sex on 12/16/16, an...

Q: I had my period from 12- 18 and realised drops of blood from 18-25.had sex on 5-10 but he produced outside .i feel bl...

Q: Hello, I took the morning after pill (19th November) whilst I was at the end of my first period and within two weeks ...

Q: Hi I had unprotected sex on my ovulation day or at least around that time. But I still had my period thirteen days a...

Q: On the poor advice from someone at Planned Parenthood (who I think was a volunteer and not a professional), about a w...


Dr. James Obaji M.D.

  • 247 Reviews
  • Family Physician

Dr. Suneel Sharman M.D.

  • 190 Reviews
  • Family Physician

Dr. Pat Golden M.D.

  • 169 Reviews
  • Cardiologist

Dr. Kunaal Jindal M.D.

  • 112 Reviews
  • Plastic Surgeon