I'm supposed to be 7 weeks pregnant but the U/S read 5-5.5 weeks. Why is that?
2007-03-09 08:22:29 · 11 answers · asked by mahnazb 1 in Pregnancy & Parenting ➔ Pregnancy
Ultrasound measurements can be off by a week or two -- that in and of itself is pretty normal. Also, you may have ovulated later than you realized, and/or implantation may have been on the later end, which also can make a difference. My question would be: why do you say you're "supposed to be" 7 weeks pregnant?
FYI, in my case we knew exactly when conception occurred (because we did IVF) -- when my OB did an ultrasound to date the pregnancy the date was "off" by more than one week. Because we knew the exact dates I was able to argue, and he re-did the measurements a few times, taking the average measurements to calculate my EDD. Each measurement was slightly different -- remember, neither the equipment nor the human eye (nor the human hand operating the equipment) is perfect, and they're using two dimensional measurements to determine the size of a three dimensional object. It's definitely not perfect!
If you have questions about the dates you should ask your doctor. If your doctor is aware that, according to your own calculations, you "should be" 7 weeks pregnant, and your doctor is not concerned based on that information and on the ultrasound, then I wouldn't worry.
ETA: Note that while it's true that pregnancy dating is a little odd and conception (ovulation) usually occurs (roughly) two weeks after your LMP that has nothing to do with the difference in ultrasound measurements -- when your doctor does an ultrasound to date the pregnancy and says you're "x" weeks, he doesn't mean you're "x" weeks post-conception...In other words, when a doctor does an ultrasound and says "you're 5 weeks pregnant" that means that conception occurred (roughly) 3 weeks ago. Hope that makes sense.
2007-03-09 09:13:51 · answer #1 · answered by ljb 6 · 0⤊ 0⤋
Not every one ovulates at the same time, so you might have not conceived when you thought you did. The first ultrasound is the most accurate, and will be the one they base your due date on. If it was less than a week difference between the two, then they go by your last menstrual period. But, in saying that ultrasounds are not 100% accurate either when it comes to dates. Did your baby have a heart beat? If so, you're further than 5.5 weeks along....
2007-03-09 08:43:54 · answer #2 · answered by Anonymous · 0⤊ 0⤋
The original estimate of how far along you are was probably estimated based on your last period, but that is not really a true estimate of when you actually ovulated and conceived. So, typically, you can add two weeks to the date of your last period and be closer to your actual due date. These are all just estimates and the doctors can never guess for sure when your baby will be born. It is very early to tell for sure though, once you go for your 20 week sonogram, there will be a lot more to see and they can better judge how far along you are.
2007-03-09 08:28:22 · answer #3 · answered by littleone78 2 · 1⤊ 0⤋
Some doctors go off of your last period while the ultrasound I believe goes off of the time of conception. While the dates are the same, it just sounds like it's off. Most women take 2 weeks to ovulate after their period, so while you think your 7 weeks based off your last period the egg didn't actually drop until two weeks after and was implanted 5 weeks ago. I was confused too because the dates didn't seem to match with me because I knew I didn't have sex that early, but the doctor explained it
2007-03-09 08:31:18 · answer #4 · answered by Melissa 3 · 0⤊ 1⤋
the way pregnancy goes is from the first day of your last period that is why you are supposed to be 7 weeks and you are only 5 to 5 1/2
2007-03-09 08:28:24 · answer #5 · answered by third times a charm 3 · 1⤊ 1⤋
The reason your two weeks off is probably because your Dr. was a little off predicting your conception date two weeks isnt really that big of a deal, it will seem like though once your 8 months preg. believe me its not going to matter, when your baby is ready then its ready, they dont go by dates. Just try to enjoy the attention you get while your pregnant and get lots of rest, congradulations!!!!!
2007-03-09 08:37:53 · answer #6 · answered by Jill T 1 · 0⤊ 0⤋
you ovulated two weeks later than other people do. It happened to me, and don't worry everything is fine :) It just buys you two more weeks to get ready for the baby lol
Congrats!
2007-03-09 08:27:49 · answer #7 · answered by Anonymous · 1⤊ 1⤋
maybe the doctor calculated your due date wrong. That happened to me. I went to the hospital 10 days past my due date. When my daughter was born, the doctor said "This baby's not post-term!" She was barely 7lbs 4 oz.
2007-03-09 08:28:02 · answer #8 · answered by Kat H 6 · 0⤊ 1⤋
my doctor told me that an u/s can be a two weeks difference. did you see the heart beat? congrats and good luck
2007-03-09 08:27:10 · answer #9 · answered by hoslnm01 3 · 0⤊ 0⤋
Trust the ultra sound. It will all come out right in the end.
2007-03-09 08:26:04 · answer #10 · answered by Anonymous · 1⤊ 0⤋