A 2005 case in which a healthy baby was nearly terminated after an ultrasound scan was misread remains one of the most cited examples of diagnostic error in obstetric imaging. This article examines what happened, what it means for patients today, and why a second opinion ultrasound scan is a legitimate and increasingly common choice.

What happened?

In 2005, a woman in the UK was told after an NHS ultrasound scan that her baby had a severe abnormality incompatible with life. She was advised to consider termination. Before proceeding, she sought a second opinion at a private clinic — where the scan was repeated and found to be entirely normal. The baby was born healthy.

The case received significant media coverage and raised important questions about the accuracy of obstetric ultrasound, the training and experience of the sonographer performing the scan, and the patient's right to seek a second opinion before acting on a serious diagnosis.

It is important to note that this case was exceptional. The vast majority of obstetric ultrasound scans are accurate, and the NHS employs highly trained sonographers. However, the case illustrates a principle that remains relevant: any significant or unexpected finding on an ultrasound scan warrants confirmation before irreversible action is taken.

How accurate is obstetric ultrasound?

Obstetric ultrasound is highly accurate for the conditions it is designed to assess. The NHS anomaly scan (performed at 18–21 weeks) detects approximately 95–98% of the conditions it screens for, including anencephaly, open spina bifida, and major cardiac defects. However, accuracy varies by:

• The condition being assessed — some structural abnormalities are more difficult to visualise than others
• Gestational age — some abnormalities are not visible until later in pregnancy
• Maternal body habitus — obesity or abdominal scarring can reduce image quality
• Equipment quality — high-resolution equipment provides better image detail
• Operator experience — the sonographer's training and case volume are significant determinants of diagnostic accuracy

False positives — where a scan suggests an abnormality that is not present — do occur, though they are uncommon. They are more likely in complex or borderline cases, and in settings where the sonographer has limited experience with the specific condition being assessed.

When to seek a second opinion scan

A second opinion ultrasound scan is appropriate when:

• A scan has identified a significant or unexpected finding and you are being asked to make a major decision based on it
• The scan report is unclear or uses terminology you do not understand
• The finding is described as borderline or uncertain
• You have been told the finding is "probably normal" but you are not reassured
• The scan was performed under suboptimal conditions (poor preparation, limited time, or the sonographer was unable to obtain adequate views)

Seeking a second opinion is not a challenge to the original sonographer's competence — it is a reasonable and clinically appropriate response to any significant diagnostic finding. Many clinicians actively encourage it.

How private ultrasound supports diagnostic confidence

At Sonoworld, our consultant sonographers have specialist experience in obstetric, gynaecological, and general diagnostic ultrasound. All scans are performed on high-resolution equipment, and verbal results are given at the end of every appointment. A written report is provided within 24 hours.

If you have received a scan result that concerns you and would like a second opinion, call us on 020 3633 4902 or book online. We will review your existing report and perform a repeat scan to confirm or clarify the findings.

Frequently asked questions

Can I request a second opinion on an NHS scan?

Yes. You are entitled to request a second opinion within the NHS. You can also seek a second opinion privately, which is often faster and can be arranged within 24–48 hours.

Will a private second opinion scan be accepted by my NHS team?

Yes. A report from a CQC-registered clinic prepared by an HCPC-registered consultant sonographer is a valid clinical document that your NHS team can act on.

What if the second opinion scan gives a different result?

If the second scan gives a different result to the first, this should be discussed with your obstetrician or midwife. In cases of genuine discrepancy, a third opinion from a fetal medicine specialist (a consultant obstetrician with subspecialty training in fetal medicine) may be recommended.