QuestionI hope you can help me cause I'm going crazy and its getting close to my
due date....I had my first ultrasound at ten weeks and it placed my due
date febraury 4th and my conception date at may 14....it also said my
LMP was april 30....what is throwing me off is that I know for a fact that
my LMP was before april 30 I just don't know when and I also have a
history of irregular periods.the reason why I'm worryed is because I had
intercourse with one guy on april 27 and another on may 12 .and I'm
really confused on who the dad can be. I hope u can help me or refer
me to another expert who can
AnswerDear Mia,
When they give you a conception date and an LMP from an ultrasound, they're not basing it on the dates you give them at all.
What they do is measure the baby, and then figure out how many weeks it is since conception, based on the baby's size and also based on what stage the baby is in forming organs and body parts.
Most times, babies grow at a very similar rate, so they can guess pretty close to when you conceived. It sounds like they gave you a conception date of on or around May 14th.
The thing with your assumed LMP is this:
Women normally ovulate approximately 14 days before they get their next period.
Medical science and obstetrics works under the assumption that all women have 28 day cycles. (Of course, most of them don't; that is just the average.)
So, according to them, if you ovulated on May 14 (which is around when you can conceive, because you can only conceive around when you ovulate), then your last period was 14 days before that, on April 30th.
But if you have 35 day periods, for example, you would still have ovulated around May 14, but your LMP would have been on April 24.
So their April 30th as an LMP is just a guess, based on their calculated date of ovulation and conception.
Based on the dates you gave me, it seems probable that May 12th is the correct date of conception.
But because the two possible dates of conception are so close together, and because you don't have regular cycles (most women don't, it's not an unusual thing) it's not possible to know with 100% certainty without a paternity test.
I wish you the best of luck,
Sheva
