HealthTap Online Primary Care Doctors Accepting New Patients
Book a video visit
HealthTap
Telehealth
A member asked:

Is it true that first trimester are off by 2 weeks i'm due may 14 from my 6 week and 9 week ultrasound so am i futher along.

A doctor has provided 1 answer

Probably: If your ultrasound dates are within 10 days of your last menstrual period dates, then you would use your LMP dates. But if you have 2 early us showing the same date that would be accurate. So, let your OB review everything and they will set your due date so there is no confusion.

Answered 2/13/2015

4.8k views

Thank

Related Questions

A member asked:

How accurate are first trimester ultrasounds at 8w1d & 9w5d done 2 weeks apart? And how much can it be off by?

5 doctors weighed in across 4 answers

A member asked:

Can a ultrasound be off almost 3 weeks? Like 2 weeks and a few days? (early first trimester)

A doctor has provided 1 answer

A member asked:

I ovulated on octomber 4th(that was CD13). According to this due date is 06/27.first trimester ultrasound(week 8) said DD is 06/23.which is reliable?

A doctor has provided 1 answer

A member asked:

Is there any way to determine twins in the first trimester other than an ultrasound its like I have a feeling that im haveing twins .. I feel like im already starting to show at 6 weeks ..?

A doctor has provided 1 answer

A member asked:

Would the gestational age of 12wks+4days @62mm be off by 1 week since ultrasounds have a margin of error of 1 week in the first trimester?

4 doctors weighed in across 3 answers

Sponsored Content
HealthTap Medical Group does not endorse products or services. Sponsored content revenues support our mission to make health information free and accessible to all.Learn more

People also searched for:

Can a first trimester ultrasound be two weeks off?
How accurate are abdominal ultrasounds in first trimester for dating how far along you are?
Could an abdominal ultrasound in the first trimester be off by a month, making me a month further along? All of my ultrasounds have given same edd.
What are the possible dates i concived with a due date of june 21st and I am now measuring a week ahead. Can first trimester ultrasounds be 2 weeksoff?
Ultrasounds in first trimester 6weeks 5 days oct.31 9 weeks 6 days nov 20 then meausring 13weeks 3days dec 11 a week ahead. could i be further then 36?

Telemedicine

Primary Care
Manage Your Conditions
Women's Health
Children's Health
Men's Health
Senior Health
Wellness, Prevention & Lifestyle
Sexual Health
Mental & Behavioral Health
Travel Medicine
Urgent Care
Ask your question
Didn't find what you're looking for?

90,000 U.S. doctors in 147 specialties are here to answer your questions or offer you advice, prescriptions, and more.

Ask your question

More of what we treat

Allergies
Antibiotics
Asthma
High Blood Pressure
Prescriptions
Type 2 Diabetes
Content on HealthTap (including answers) should not be used for medical advice, diagnosis, or treatment, and interactions on HealthTap do not create a doctor-patient relationship. Never disregard or delay professional medical advice in person because of anything on HealthTap. Call your doctor or 911 if you think you may have a medical emergency.
HealthTap
HIPAA logo
HIPAASecure
Soc 2 Type 2 logo
SOC 2 Type 2Certified
JCAHO Accredited
JCAHOAccredited
Member App

Download HealthTap

Video visit and message your doctor

Member App QR Code
Play Store Member LinkApp Store Member Link

Questions?

+1 (888) 828-0841support@healthtap.com
LinkedInTwitter
HomeTermsPrivacyCookiesDMCAHealth TopicsDoctors DirectoryDoctor Q&A by Specialty
Copyright 2026 HealthTap, Inc.