ultrasound question??

[kathrynpaige98]

I had an ultrasound yesterday 1/19/2021 (12 weeks 6 days from LMP) when they did the crown rump length and stuff i was measuring between 11 weeks 2 days and 4 days. Does this mean that I ovulated later and they think I conceived around 9 weeks ago or does this mean i conceived around 11 weeks and 4 days ago? Basically did I get pregnant from october 19th or around nov 2nd- 4th sex? My hcg levels were 167 on november 25th.

[AnnieBrooke]

The gestational-age (GA) counts of the pregnancy time period used by doctors, nurses, medical books or even ultrasounds begin the count of weeks at the first day of your last period. No, they aren't saying you conceived on the first day of your last period, they are saying that is when the pregnancy time frame begins. If you were told you were around 11 weeks GA, they were telling you that you conceived about 9 weeks ago.

[kathrynpaige98]

@anniebrooke my LMP was 12 weeks and 6 days ago though. thats why im confused. because it was october 21st but the crown rump length and all that was bringing me around 11 weeks and 4 days ago. so that just means i ovulated later then?

[AnnieBrooke]

Sounds like it. There isn't always a relationship between the last period a woman has had and her next ovulation. Ovulation is the start and the period is the finish, rather than the other way around, and a woman's body can wait a while before ovulating again.

[kathrynpaige98]

@anniebrooke so you dont think theres anyway id be pregnant from sex on october 19th?

[AnnieBrooke]

Kathryn, what date did they give you as the estimated due date? It's really easy to get wrapped around the wheel when using "weeks" counts to try to figure this out.

[kathrynpaige98]

@anniebrooke they gave me between july 28th and first week of august. I wont know for sure until my actual obgyn reviews my ultrasound.

[AnnieBrooke]

And, when you had ultrasounds earlier, did they give you estimated due dates?

[kathrynpaige98]

this was my first ultrasound from an actual obgyn. I had a private one and i was also measuring 7 weeks 2 days instead of 8 weeks 6 days but didnt get an EDD

[AnnieBrooke]

Once your medical team sees the baby on the ultrasound and measures it, when your actual last period came becomes insignificant from a medical point of view. (After all, a woman's last period could have come a year ago. They wouldn't be telling her that the baby was 52 weeks along, they would look at the baby to see how far along it was.)

Ultrasound evidence is, you didn't conceive earlier than November 4. Talk it over with your doctor if this doesn't make sense to you.

[kathrynpaige98]

do they always add 2 weeks to ultrasounds? like if it says 11 weeks does it mean 9 weeks?

[AnnieBrooke]

Any medical mention of gestational age (including ultrasounds, medical textbooks and "What to Expect When You're Expecting") uses the 40-week time period to count out a pregnancy. The first two weeks of that 40 weeks are the time between the first day of the woman's last period and conception, and the next 38 weeks are from conception to (full term) birth. Once the embryo is seen and measured on an ultrasound, they have a good idea when it was conceived (if the ultrasound is early), and then count back two weeks from that conception date to begin the gestational-age count. This means that if someone's actual period is way off what the conception date of the baby says, the medical people (doctor, ultrasound tech, everyone) will go with what the ultrasound says. And yes, ultrasounds notate the GA the same way as the doctor does.

Again, as I've already said, don't get all wound up about the "weeks" count, work from your estimated due date. It's lots less confusing.

[kathrynpaige98]

Thank you :)