Avatar universal

Conception date doesn't match due date

First thank you in advance for taking the time to look over my question.
I am pregnant about to be in my 7th month. I have been confused for some time however, about my due date not adding up to my conception date.
I wasn't having intercourse for months and one night with a friend I had protected and unfinished sex may 11th. Unexpected and unsatisfying. I then had unprotected sex the next weekend on the 17th with another man that I have been seeing on and off for years now that was finished and satisfying and he did ejaculate inside of me. I found out 2 weeks later that I was pregnant. I told both men but I was more than sure that the second man was the father considering unprotected vs protected. However I still knew it was a very slim possibility. Looking back at my cycle at the time I also believed I was ovulating the weekend of the 17th. But I could not give a good estimation of my last period. I just know it was in the beginning of the month.
My first ultrasound in the room the tech told me how far along I was (11weeks) which added up perfectly from who I absolutely was sure it was the 17th. However the doctor I saw after the ultrasound I assume went off of growth of the baby or off of a possible inaccurate LMP estimate. But they told me I was 12 weeks which was a week ahead which would add up to the first guy on the 11th. Then proceeded to tell me my due date was on the 1st of February. But according to my thought of conception date (17th of may), my estimated due date should fall around the 7th-10th depending on my cycle which I can't remember exactly for the life of me.
I would really appreciate any kind of help at this point. And if the best answer is to get a paternity test. That can be done. Thanks again for your time.
7 Responses
13167 tn?1327194124
Susan,  I think you've considered this situation very thoroughly and I don't see how  anyone could possibly add anything to it that would be enlightening.

Best wishes.

10707428 tn?1415569790
I dont know about your situation, but i can tell you my experience. When you dont know the exact day of your last period, its really hard for them to see how far along exactly you are.

My last period was on April 21st. I went for my first ultrasound when i was suppoused to be 10 weeks. they told me i was 6 weeks not 10. That confused me because i missed my period in May and now they count it as if i had it. Then when i was 21 weeks, (counting as it said on the ultrasound the first time) they told me it looks like i was 18 weeks not 21. which didnt make sense, because then the first time i would've been 3 weeks pregnant which they wouldnt see anything, there's no way they could mistake that for 6 weeks, so i keep counting as if i was 6 weeks the first time. Now whenever i go they say some different week i am in, and its never the one i keep counting as. Different babies develop differently and they can be one or two weeks off, thats what the doctor told me.
Avatar universal
Hey.. i am a hundred percent sure of all my dates and everything and I've only slept with my husband on a specific date and my baby is still 8 days older than expected.. so a week's difference in dates is not that big of an issue.. the dad could be the 17th guy in your case, your baby just grew faster like mine..
Avatar universal
Paternity test is of course the answer. At the end of it all you don't want to have the wrong person raising your child but the guy on the 17th sounds like the more accurate choice because he was the one of the two that did ejaculate in you. Good luck and best wishes. God bless
Avatar universal
I'm facing a similar situation, I had my lmp on the 3rd August I had sex with my bf the 9,10,16 and 17th August, in September I had no sex but my period was on the 10th or the 12th September and it was light and lasted for two days,I then had unprotected sex with my ex on the 3rd October and I took the emergency pill,I discovered I'm pregnant late October and went for a scan on 5th November and based on measurements of the womb it was saying I'm either 6 or 8weeks pregnant,but the Dr claims I got pregnant mid august but aren't my weeks supposed to be more?
Avatar universal
My due date doesn't match up either. I never had sex anywhere near my date of conception. Also I had already gotten a positive pregnancy test by my "date of conception" my baby measures 3 weeks ahead which would go with when I was sexually active. Even my doctor Thinks my due date is off but they won't change it.
Avatar universal
If you have unprotected sex, the guy doesn't not have to finish for you to get pregnant. Pre-ejaculate contains sperm  and can cause you to get pregnant. You will need a paternity test to know for sure.

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