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Avatar universal

my conception date

I recently found out I was pregnant, and my last period started August 29,2014.  Based on that information, my doctor and my due date calculator concur that my baby was most likely conceived between the 9th and 13th of September.  Is there any way that the baby could have been conceived earlier than that?  I have a due date set as June 4, 2015, and really want to know that there was NO possibility that my baby was conceived any time at all in August.  Help please!!
Best Answer
134578 tn?1693250592
COMMUNITY LEADER
Your last period is a helpful clue, but not 100% reliable for some women, when trying to determine the date of conception.  It all depends on how clockwork your cycles are.  If you have a period on the dot every 28 days, you're in good shape.  If they are irregular or long, you might have a window that extends into August.

Get an ultrasound in your 7th week (starting the count of weeks on the first day of your last period).  Ask the doctor to give you an estimate of your due date based on the crown-to-rump measurement of the embryo and other developmental markers.  If that independently confirms the date you get from your last period, then you could rely on the window the doctor gave you.
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Avatar universal
Thank you so much!  I have an appointment scheduled for the 24th which based on the above information would make me about eight weeks.  I'll do what you said for sure!  
Helpful - 0
Avatar universal
I'm just nervous because the period that started on the 29th of august was very light and only lasted three or four days.  
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
The ultrasound will tell you what you need to know.
Helpful - 0
Avatar universal
I went to the doctor on the 24th and my doctor didn't do an ultrasound at all!  She said I was too early to hear a heartbeat anyway!  I was devastated!!!  However she scheduled an ultrasound for November the 21st, and it's got me absolutely stressed out.  She is still estimating me as nine weeks about now, but I still have my doubts.  I am really scared about this...
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Avatar universal
The worst part of everything is that I am with a man I've been with for five years... He and I went through a rather rough patch for a few months and he became very distant.. He brought home a treatable bacterial std...  We had no sex whatsoever for quite some time, months actually.  I gave in to my kids father two weekends in august because of my anger for my boyfriend and need for affection.  I know it was wrong, and I should never have done it, but oh my goodness am I terrified that this baby will be his!  He is not a good father to our first two kids, and I feel like an idiot for having done this.  I had my period still, august 29th, but it was shorter than normal... that's what has me scared....  When my period didn't come September 29th I knew something was wrong.  I went on the 30th and bought a test and sure enough it was positive.  I have been stressed out ever since, and very emotional.  I would give anything for it to be my current boyfriends....  He did bring home the infection, but was treated and has done a complete 360 after we separated.  I wish so bad I could have just remained strong and to myself so that I wouldn't be so afraid right now.  
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Avatar universal
You could go to a cpc and get an ultrasound I think it's called crisis pregnancy center or central pregnancy community. It should be free
Helpful - 0
Avatar universal
Hi im going thru the exact same thing as yu but see mine is more stressful i had sex w an ex outta anger sept 8th but he pulld out & came on a shirt,
I also had my period aug 29 but mine as well was light nd ended the 2nd but iv been having irregular periods for couple months now,im so terrified that it would b my exs bby i knw d pull out method isnt 100% safe,but i missd my period sept 29-30th took a test on oct 1st and it was negative, did another test oct 6th it was a faint positive so next day went to a free clinic they did 2 ultrasound sounds the regular one and vaginal and couldnt see anything they said i was too early,so they told me come bak 3wks later that ill be 7wks and can see the bby i went to a different location and by measurements i was 6wks 5 days which today ill be 7wks 2days,the heart beat was normal at 120 ,but i honestly dnt knw if it is my ex or my current bf,my current bf says he craves sweets but idk if he jus says that im so scared,i wish i knew,
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
mtorres, I would schedule somewhere else with a different doctor where you can get an ultrasound.  If you have to wait until November 21 it will not be as helpful as if you were able to get it earlier.  Did you explain to your doc that you really need to know for dating purposes?  Did you offer to pay out of pocket for the ultrasound?  The earlier the better for this purpose.
Helpful - 0
Avatar universal
What doctor can't find the heart beat at 9 weeks?
I saw my babies heart beat at 7 weeks!  I think you should definitely go to a new doctor.
I went to the ER for my first ultrasound because I thought I was miscarrying.
Helpful - 0
Avatar universal
I don't know why she didn't do the ultrasound at first, but I was devastated!!!  The 21st is next week so it is probably too late.  I am ready for whatever, but on a positive note I haven't grown any, I still wear my normal clothes, and all of the symptoms point to me truly being 11 weeks. (which would mean I was safe)  I'm so scared for the 21st, but at this point I'll just have to deal with it.  I just don't know what to do.  The biggest issue is, my current significant other is black... my kids father is Puerto Rican like me... So I am so very afraid that I will deliver this very white baby in front of my bf who up to date is so excited about the pregnancy.  I don't think I could live with myself.  anniebrooke, it's hard to schedule else where for the ultrasound because it's hard enough to get the time off to go to one doctor let alone two.  
Helpful - 0
Avatar universal
I truly don't know!!!  I was so pumped because I thought I'd catch it early on, but that's what she said.  it makes me so upset because I wish I had insisted on it while I was there, I should have said something.  I think it's because I'm so ashamed of what I've done.  I guess I didn't want her to think I was a ***** (I'm definitely not)  I promise I've never slept around on him before, and I was so angry about the std and the FACT that he'd slept around on me, I thought it would be the ultimate get back by sleeping with my kids father.  In the end it was more on me, because I left him for a reason, and I wish so bad I'd never done this.
Helpful - 0
Avatar universal
I took my test on the 1st of October, when I didn't get my period sept 28th I knew something was wrong.  I gave it a couple of days to be sure.  When I took my test the lines showed up INSTANTLY.  There was no question about it.  I didn't have sex with anyone but my bf in September.  It was only in august that I did.  I'm really so scared right now, and now everything I'm reading about this ultrasound is freaking me out even worse.
Helpful - 0
Avatar universal
Why won't the ultrasound be as helpful??? will they not be able to tell?
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
I was saying to change doctors, not to get one appointment with one and another with another.  

The reason ultrasounds get less helpful for dating purposes as time goes by is that all embryos begin as one cell, and then split into two cells, then four, then eight, then sixteen, and this happens at a known rate.  An IVF technologist can tell you how old the blastocyst is by looking at it through a microscope and counting how many cells it has split into.  But after a while, once the embryo has implanted and begun to grow, some babies grow faster than average and some grow more slowly.  Therefore, an ultrasound in your 6th week has a margin for error of possibly +/- 1 day at most for purposes of dating the pregnancy, since it is so close to the beginning of the pregnancy.  But by the 12th week, growth rates have begun to diverge (or not) and the margin for error is +/- 7 days, and by the 40th week, it is +/- 21 days.
Helpful - 0
Avatar universal
oh ok... I think I should still be ok then, because whatever happened happened mid august.  I was active with my boyfriend / fiancé from the first weekend of September and ongoing through out the month.  I'm really praying for a good out come.  He is so excited and so is his family, and I swear I would never be able to live with myself...  I sincerely thank you for all of your advice, and I assure you I will post an update after the 21'st comes and goes to let you know what the outcome was.  I am praying I will be measured at 11 to 12 weeks.
Helpful - 0
Avatar universal
Hello there!  I know I promised an update after the ultrasound, and I'm very late :-) good news I measured right non schedule.  I am now at nineteen weeks (tomorrow) and I feel a lot more comfortable about everything.  I won't lie, I am still worried... but way less worried than I was before.  I will continue to pray that everything works out well for us, because quite honestly this is the best pregnancy I've ever had.  I really don't want this to turn out badly, and I just wish I didn't have to be so worried.  I wish I could be confident about him being the father of this baby.  I just can't.
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
It sounds like everything is coming out as you hope.  Try to stay calm.
Helpful - 0
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