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Avatar universal

Conception date, trying to determine ovulation

I had my last period on December 24, 2016, my cycles have been a bit irregular in the past few months but prior to they were about 33-35 day cycles.  I think they were irregular due to medication.  I had sex all of January with the same guy off and on without protection, I had sex a different guy on January 21, however, he pulled out before ejaculating all over me.  I am hoping the first guy is the father of my child, but I can't stop thinking about the slight chance of the other.  I had spotting on January 23-25, it was dark brown and off and on all day long.  I went to the doctor on March 7th and had an ultrasound making my due date October 11.  At my next appointment, I told the dr about my LMP being December 24th and she changed my due date to October 7th.  With these dates, It is said that my ovulation and fertile period should have been between January 12-18.  I do believe this to be true because I was tracking my CM and symptoms.  Also, the january bleeding seems to be implantation bleeding.  I just want some insight on the situation.  
2 Responses
134578 tn?1546634665
Go with what the ultrasound showed, not what the doctor changed it to.  Use the system where the actual embryo was seen and measured, not a system that counts forward from the first day of your last period and assumes regular 28-day cycles that you don't have.  

If you were at the doc March 7, would this have been in your ninth week or so?  The ninth week is already is late enough in the pregnancy that there is a margin for error when using the baby's measurements to try to compute when you might have conceived.  Most doctors would say "give or take a few days" when trying to do this kind of estimate in your ninth week.  The calculator gives January 18 for conception if the due date is October 11, meaning that the margin for error in your ninth week is not helpful.  It rules both guys in.  

I would operate on the assumption that either guy might have gotten you pregnant, and do a DNA test with them both.  You can do this before the baby comes by a simple blood draw from your arm and swabs from the guys (using the labs Ravgen or the DDC), if you have the big money it costs to do a prenatal test.  Or you can do it for a tenth of the cost after the baby comes.  But be sure to test with both guys.
Ok.  Well the Dr didn't assume it was a 28 day cycle she based the date off of my 35 day cycle.  The second guy is someone who I have no contact with anymore, it was a once night stand and I will not be in contact with him anymore so I am praying that it was not him.  I feel like the brown bleeding or spotting on the 23 would lead more to the first guy because the earliest you can have implantation bleeding is 6 days after conception.  
Also, I was tracking ovulation with an ovulation kit and I had a peak high on January 14th.  I just can't imagine or think about it even being the second guy, and if I can't test him should I still test the first one?  
Sure, test with whomever you can test.  The reason I say test with both, is if you get a negative with him you will need a positive from the other guy to be certain the first guy didn't cheat the test by getting a buddy to go to the lab for him or by using someone else's swab.  Especially if from a prenatal test, it is not uncommon for the woman to not believe a negative unless she gets a positive from the other person.  (It sounds like that is not a logical reaction, but women write in ALL THE TIME asking "What if the test was wrong?!?!?!?")  

"Implantation bleeding" is largely a myth perpetuated on the Internet by women who hope having bleeding proves something about when they got pregnant.  An embryo implanting is no larger than the dot on the i in this sentence, it will not make a woman bleed or spot for a day.  The bleeding you had is actually more likely to have come from the cervix getting bonked during sex than from a tiny, tiny embryo burrowing into the uterine lining.

If your doctor based your first due date on the ultrasound and then changed things based only on when your periods were, the first due date is more accurate than the second.
... though as I said, because it wasn't in your 6th or 7th week, it can't be considered pinpoint.

Again, I'm sorry, but it will take a DNA test that comes up a clear positive to be sure of who the dad is.
First, my dr told me about implantation bleeding so how is it a myth? Are you a dr I am thankful for advice but not if you are going to share information that you could be making up. And the first guy is someone I am with so I'm sure they won't cause a reason for a false negative.
Sounds like you have it all figured out, then.
Regarding your comment about you not wanting advice because you think I am making things up, I would say that out of a thousand times on this site a woman has asked if some bleeding she had was implantation bleeding (a subject sometimes talked about in the DNA/Paternity forum and very often talked about on the trying-to-get-pregnant communities), about nine hundred ninety nine of them turn out to be their period or blood from their cervix from having sex, not implantation bleeding.  I didn't say it did not exist, I said that it is *largely* a myth. (Women will look right at their period and hopefully say "was that implantation bleeding?" or will work out their dates and fearfully say "what if that was implantation bleeding and not my period?") It is possible that some women have it, but it is described as just a little whisper of blood noticeable on a pad once.  The embryo is very tiny and the uterus is built to accept it.

I get that you don't need this advice or any from me.  Your doc is the best advisor for you.  
Yes and I'm sorry for being snippy.  My ultrasound wasn't on the 7h of march I don't remember the date but it is dated as 8 wk 2 days when I had it and it said due October 11 and then again at 19 wks I was dated October 11 and am having a girl
Avatar universal
I am sorry if I sounded snippy.  My first ultrasound was done when I was 8 weeks and 2 days and that dated me for October 11 I got my second one for 19 weeks and it also dated me October 11.  I found out it's a girl as well.
It all sounds hopeful.  Good luck to you.
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