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Dr Pixel 2.0Women's imaging diagnosis

PLATFORM FOR EDUCATION AND DECISION SUPPORT IN WOMEN'S IMAGING

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Interactive checklist

Answer the questions in order. The checklist applies NICE 2023 criteria and automatically shows guidance as you fill in the fields.

Recommended sequence (NICE)
  1. When performing an ultrasound scan to assess the viability of an intrauterine pregnancy, first look for fetal cardiac activity.
  2. If no cardiac activity is seen but an embryo is visible, measure the crown–rump length (CRL).
  3. Measure the mean gestational sac diameter (MSD) only if the embryo is not visible.
Follow-up

Minimum recommended follow-up interval (NICE 2023)

  • •Transvaginal: minimum interval = 7 days
  • •Transabdominal: minimum interval = 14 days

Always repeat under adequate technical conditions and consider dating uncertainty.

Limitations

Limitations / caution

  • •Not validated for patients under 18 years.
  • •Not applicable when ectopic pregnancy is suspected.
  • •Does not replace clinical assessment; in instability/bleeding, prioritize emergency care.
  • •Do not use LMP alone to decide when cardiac activity should be visible.
  • •Cycle variability may lead to dating error.
  • •Uncertain dating / very early scan.
  • •Clinical–ultrasound discordance.
  • •If diagnosing complete miscarriage without a prior scan confirming an intrauterine pregnancy, consider pregnancy of unknown location (PUL) and follow-up.
Disclaimer

Educational tool based on NICE guideline NG126 (2019, updated 2023). Does not replace individual clinical assessment.

References
  1. National Institute for Health and Care Excellence (NICE). Ectopic pregnancy and miscarriage: diagnosis and initial management. NICE guideline NG126. London: NICE; 2019. Updated 23 Aug 2023. Available at: https://www.nice.org.uk/guidance/ng126
Understand the criteria

NICE 2023 criteria for non-viable pregnancy

Diagnosing non-viable pregnancy by ultrasound must follow strict, standardized criteria to avoid false positives and premature decisions. This app brings together, in a didactic and illustrated way, the criteria from the NICE guideline NG126 (2019, updated 2023), highlighting when the diagnosis can be made safely and when follow-up is required. Educational decision-support tool, not a substitute for clinical assessment.

Two numeric thresholds, with no visible heartbeat/embryo

NICE 2023 thresholds (not conclusive in isolation)

CRL with no cardiac activity≥ 7 mm
Suspicious finding — requires follow-up
Strongly suggestive of non-viability
0 mm7 mm14 mm
MSD (mean sac diameter) with no embryo≥ 25 mm
Suspicious finding — requires follow-up
Strongly suggestive of non-viability
0 mm25 mm50 mm

Strongly suggestive of non-viability, but not necessarily conclusive (NICE 2023)

  • Embryo with CRL ≥ 7 mm (TVUS) with no cardiac activity.
  • Gestational sac with MSD ≥ 25 mm (TVUS) with no embryo.

Suspicious findings — require follow-up; do not conclude on the initial scan (NICE 2023)

  • CRL < 7 mm with no cardiac activity.
  • MSD < 25 mm with no embryo.

Minimum recommended follow-up interval (NICE 2023)

  • Transvaginal: minimum interval = 7 days
  • Transabdominal: minimum interval = 14 days

Always repeat under adequate technical conditions and consider dating uncertainty.

Caution: a diagnosis of non-viable pregnancy based on a single ultrasound scan is not 100% guaranteed, especially at very early gestational ages. There may be a small chance of error.

Common questions

Frequently asked questions about non-viable pregnancy

What are the NICE 2023 criteria strongly suggestive of non-viable pregnancy?+
An embryo with CRL ≥ 7 mm on transvaginal ultrasound with no cardiac activity, or a gestational sac with mean sac diameter (MSD) ≥ 25 mm on transvaginal ultrasound with no embryo. The guideline classifies these findings as strongly suggestive, but not necessarily conclusive on their own.
What should be done when CRL is under 7 mm and no cardiac activity is seen?+
This is a suspicious but not conclusive finding — it requires follow-up rather than a conclusion at the initial scan. If measured transvaginally and no cardiac activity is visible, repeat the ultrasound after at least 7 days before making the diagnosis.
What is the minimum recommended interval between scans to confirm the diagnosis?+
The minimum recommended interval is 7 days for transvaginal ultrasound and 14 days for transabdominal ultrasound. The repeat scan should always be performed under adequate technical conditions, considering dating uncertainty.
What is the recommended sequence when assessing pregnancy viability?+
First, look for fetal cardiac activity. If no cardiac activity is seen but an embryo is visible, measure the crown-rump length (CRL). Measure the mean gestational sac diameter (MSD) only if the embryo is not visible.
Does this tool apply to any patient with suspected miscarriage?+
No. It is not validated for patients under 18, does not apply when ectopic pregnancy is suspected, and does not replace clinical assessment — in cases of instability or bleeding, emergency care must be prioritized. It should also not be used alone, based on LMP, to decide when cardiac activity should be visible.
Is a diagnosis of complete miscarriage without a prior scan confirming intrauterine pregnancy reliable?+
Not necessarily — in that scenario, pregnancy of unknown location (PUL) should be considered, along with the need for follow-up, since there is no prior confirmation that the pregnancy was intrauterine.