Expert: Catherine Beier MS CBE - 2/6/2012

Question
QUESTION: I have a question, i have pcos, irregular cycles from time to time, but recently was getting regular cycles, but anyway, i had sex with ex on august 4th or 5th, one time pullout method, the rest of august i had sex with current boyfriend, on sept 16th i went to hospital for cramps and pain, found out i was pregnant, hcg level was 241, went back 2 days after and it doubled, on transvaginal on sept 16th it showed nothing. i went back on sept 28th for transvaginal and it showed iwas 5 weeks 5 days, i had a few more ultrasounds done, they all gave the due date of may 25th give or take a day. i went again today which is my 21 weeks and 3 days. again it measured the same. so my question is. did i get from pregnant from august 4th or 5th intercourse? my conception date is spt 2nd, but everyone says can be off.. i cant enjoy this because i do not know. i need help :[

ANSWER: Ash,

There is no way you conceived on August 4th or 5th.  Absolutely none. Zip. Zilch. Nada. Early transvaginal ultrasound is the most accurate way to date a pregnancy and has a standard error of measure of +/- 1 day.

It is the second man's baby and there is no doubt about it.


Best,
Catherine

---------- FOLLOW-UP ----------

QUESTION: So even from sex on aug 5th theres no way sperm could live that long and the implantation process?? I am just really worried!!!! The doctor says i conceived in middle of august if that makes any sense...so maybe thats just a timeframe?? Sorry i just need to know thanks!!!!

Answer
I'm not certain how my last answer was unclear, but NO you could not have conceived on August 5th.  Like I already said, early transvaginal ultrasound is THE most accurate way to date a pregnancy and is accurate to +/- 1 day.  If you were 5 weeks, 5 days on Sept. 28, this gives a conception date of Sept 2, not the middle of August.  If you had conceived on Aug. 5th, the ultrasound would have shown that you were 9 weeks pregnant.