Negligent Misdiagnosis of a Blighted Ovum

Following the recent UK scandal relating to misdiagnosed miscarriages, the UK has created new guidelines for diagnosing blighted ova. Unfortunately, miscarriages and blighted ova are still being misdiagnosed in Irish hospitals and patients may have a claim for clinical negligence against the hospitals and consultants responsible for the misdiagnosis.

What is a Blighted Ovum?

A blighted ovum is a fertilised egg that implants but does not develop. The gestational sac continues to grow but the baby does not grow within the sac. This does not mean that there was no embryo. The embryo is most likely to have died very early in the pregnancy and would have been reabsorbed into the body early in its development. Most embryos which are lost this way, would have had severe chromosomal abnormalities and therefore, could never thrive. An embryonic Miscarriage is typically detected between 8 and 11 weeks into your pregnancy. A D&C is usually necessary in this case.

The standard criteria used for diagnosis of a blighted ovum, up until the new guidelines were released, was:

1. Failure to identify an embryo in a gestational sac measuring at least 20 mm via transabdominal ultrasound.
2. Failure to identify an embryo in a gestational sac measuring approximately 18mm or more via transvaginal ultrasound.
3. Failure to identify a yolk sac in a gestational sac measuring 13mm or more.

What are the new UK guidelines?

In summary, the Royal College of Obstetricians and Gynaecologists say that a doctor should monitor a growing gestational sac until it reaches at least 25mm. Then, the doctor can get a second opinion or diagnose a blighted ovum. The reason for this is that many women who have a tilted uterus look one to two weeks behind. If practitioners wait until the gestational sac measures at least 25mm,that would get them to about the nine week mark which is when a number of women seem to find their babies.

Ultrasound Technology

No test in medicine is 100 per cent accurate, something that is easily forgotten as technology rapidly advances. It is routine practice in the situation of suspected miscarriage for a second assessment to take place before any definitive management decisions are made. Knowing that the ultrasound’s measurements could be off by 4mm or even 5mm, which in turn could make a big difference in a diagnosis. That is why, as hard as it is to wait, if the sac is measuring 25mm, you may want to wait just one more week to verify. Of course, this should only be done if there are no serious complications.

Issues that may have contributed to the initial misdiagnosis include the quality of the ultrasound machine in the emergency room and the experience of the non-consultant doctor who carried out the test. But it has to be said that even an experienced consultant will occasionally, for a variety of reasons, fail to detect a foetal heartbeat.

Irish Position

In 2010 it was revealed that inadequate staff training and over-reliance on ultrasound led to 24 women being wrongly told they had suffered a miscarriage, an inquiry has found. The Health Service Executive (HSE) apologised after the national miscarriage misdiagnosis review revealed there had been no mandatory training in ultrasound in half of the cases examined.

Two of the women suffered miscarriages after undergoing a medical procedure to remove the foetus, while 22 went on to give birth. The inquiry was launched in June 2010 when Dublin mother Melissa Redmond revealed she had a baby boy after she was informed she had miscarried and was told to have a procedure known as dilation and curettage, carried out after a miscarriage, and an abortion-inducing drug.

The review of 24 cases of misdiagnoses in June 2010 showed: Consultants and registrars accounted for 79 per cent of health professionals who made the false diagnoses. Medication to aid the miscarriage of a foetus was prescribed to eight women. Six women underwent an operative procedure.

Formal training in early pregnancy ultrasound was reported by only three of the clinicians who made an initial diagnosis. In 12 cases there was no mandatory training in ultrasound within the hospital at the time the case occurred. Eight hospitals did not have an early pregnancy assessment unit at the time of the diagnoses. In six cases the scanning machine was more than five years old.

The 24 misdiagnoses occurred at the very early stages of pregnancy, when ultrasound diagnosis alone is unreliable due to the risk of missing a tiny foetus or heartbeat. Over-reliance on ultrasound to diagnose a miscarriage in very early pregnancy has been repeatedly highlighted since the introduction of the technique in the 1970s and we have made recommendations that caution against the use of ultrasound alone to detect a pregnancy before eight weeks gestation.

The above topic is one area we can discuss with you, and we can discuss any form of medical negligence with you on a confidential and sympathetic basis.

To discuss your case in confidence, please telephone 01-5313800 or email us for further information.