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Built by a practicing radiologist

Fetal biometry, measured right.

Watch how it's done — then run the numbers: gestational age, estimated fetal weight (Hadlock) and growth percentiles, all in one window.

Ultrasound Academy · How to perform fetal biometry
↓ Open the fetal calculators 🤰 I'm pregnant · patient portal →
Hadlock EFW Growth percentiles CRL & biometry dating Doppler indices
Obstetric calculators

Run the numbers — right here.

Enter the measurements and get the result instantly, on this page. Real formulas (Robinson, Hadlock, Naegele) — no login, nothing to install.

160+

All calculators

TI-RADS, biophysical profile, volumes, nuchal… the full set on the platform.

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🤰 Are you pregnant?

This page is for clinical measurements. If you're expecting, the patient portal explains your exam, what to expect and your report — and helps you follow your pregnancy.

Go to the patient portal →
Gender reveal ultrasound challenge

Discover the baby's sex: can you tell before the reveal?

Pause the clip, make your guess, then watch the answer. These Ultrasound Cases playlists turn fetal sex recognition into a fast, playful challenge with real scan clues.

1. Watch the clueLook at the angle, the view and the fetal position before the reveal appears.
2. Pick a sideCall Team Pink or Team Blue before the countdown ends.
3. Reveal & learnCompare your guess with the final answer, then jump to the next case.
Team PinkGirl?
Team BlueBoy?
Open the quiz playlist → Watch the complete guide

Educational challenge only: fetal sex assessment depends on gestational age, fetal position and scan quality. Confirm clinically when timing and image quality are appropriate.

How dating works

The right parameter for the right week.

Dating accuracy depends on which biometric you use and when. The calculators apply the accepted method for each window so your gestational age holds up.

First trimesterCrown–rump length (CRL, 6–13 weeks) — the most reliable dating, ±5–7 days.
Second / third trimesterA combination of BPD, HC, AC and FL, with wider intervals as pregnancy advances.
Growth vs. datingOnce dated, later scans assess growth against percentiles — not re-dating.
Obstetric report models — live

Now put the numbers in a report.

Open any obstetric model and try it right here: pick findings and watch the report write itself — the same modular engine behind Sono AI Report.

Dr. Pedro Pontes
Why trust it

Built in a real reading room.

FetalBiometry.com is part of Sono AI Report, created by Dr. Pedro Pontes — a radiologist who reports ultrasound every day. Published formulas, cited references, an editorial policy you can read.

DR. PEDRO PONTES · RADIOLOGIST · CRM 14742 · RQE 9622 · MEMBRO TITULAR DO COLÉGIO BRASILEIRO DE RADIOLOGIA

LinkedIn Ultrasound Academy

From measurement to report.

The calculators live inside a full ultrasound reporting platform — dictation, templates and a branded PDF. Try it free.

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