Merrion Fetal Health follows the guidelines of The National Maternity Hospital and the Royal College of Obstetricians & Gynaecologists to ensure that misdiagnosis does not occur. These guidelines err on the side of caution and outline strict criteria for making the diagnosis of miscarriage.

The guidelines run to 18 pages and make many recommendations but broadly speaking an ultrasound should be carried out by appropriately trained personnel with appropriate ultrasound equipment (including transvaginal probes). In many cases, a fetus/embryo with a regular heartbeat will be identified in a healthy pregnancy sac within the womb. The ultrasound allows measurement of the size of the fetus and the sac to determine how far the pregnancy is. Sadly, it is often the case that we identify an embryo/fetus in a pregnancy sac but cannot see a heartbeat and this may mean the pregnancy is too early or not viable.

Because of the difficulties in seeing a heartbeat in very early pregnancies, there are strict criteria which we follow to ensure that we do not diagnose a miscarriage in what could be a healthy but very early pregnancy where it is not possible to see the heartbeat yet. Thus, if the pregnancy sac is less than 20mm in size or if the size of the embryo/fetus is less than 6mm and a heartbeat cannot be seen, a definitive diagnosis cannot be made and the scan should be repeated in 7 to 10 days time.

An internal scan allows better visualisation of the womb and its contents. This is because the soundwaves do not have to travel far because the tip of the probe is inserted very close to the womb and gives a much better picture than an abdominal (transabdominal) scan. With this approach, the soundwaves have to travel through your tummy wall and occasionally the images obtained are not clear enough to make a definitive diagnosis. Thus, in very early pregnancy, in overweight women or when the womb is tilted backwards, or when a clear diagnosis cannot be reached with a transabdominal scan, a transvaginal approach might be necessary.

This is a very common scenario because the hormones that are released by an early pregnancy that is failing can still cause pregnancy symptoms.

Again, the hormones that are released in early pregnancy can give a positive pregnancy test. These hormones can stay in the blood for some time after the pregnancy has failed and will give a positive pregnancy test as these hormones are released into the urine which then gives a positive pregnancy test. This can occur for up to 3 weeks following any type of miscarriage.

It is very often unnecessary to do this as the first scan diagnosis can be definite if the above criteria can be met. If there are any doubts about diagnosis a second scan will be performed, sometimes on the same day, but more often 7 – 10 days later. Some women miscarry completely and the womb or uterus will appear empty when scanned. In this case, no follow up procedure will be necessary.

Occasionally, ultrasound in early pregnancy may be inconclusive if the gestation is too early, particularly if you are less than 7 weeks or if you are unsure of your dates. This is because the pregnancy may be too small to be seen before 7 weeks. In order to be absolutely accurate in the diagnosis of early pregnancy before 7-8 weeks, it is recommended by all best practice guidelines, to repeat the scan after an interval of at least a week, if there is uncertainty or doubt.

All bleeding that occurs in the early weeks of pregnancy is referred to as a threatened miscarriage. Viability is uncertain in about 10% of pregnancies. Under 7 weeks a diagnosis can be difficult. When a miscarriage is suspected, an ultrasound scan is carried out to establish what the likely outcome will be. If it is confirmed that the pregnancy is not continuing, the scan findings will suggest whether there is a need for further treatment. Some women miscarry completely and the womb or uterus will appear empty when scanned. In this case, no follow up procedure will be necessary.

There are various treatment options which would include awaiting for a spontaneous miscarriage which usually involves heavy bleeding, similar to a heavy period. This approach might be recommended if there is a small amount of tissue in the womb. An alternative treatment would be to use a medication called Cytotec which might induce a miscarriage and is also used prior to ERPC/D&C. If there is a big pregnancy sac and/or a lot of tissue in the womb the usual recommendation will be to undergo an ERPC/D&C.

ERPC stands for Evacuation of Retained Products of Conception and is a procedure performed under general anaesthetic that involves removing the remaining blood clots and pregnancy sac from the womb in order to stop further bleeding. Although instruments are passed into the womb no actual surgery takes place and no stitches are needed.

If you decline to have an ERPC (D&C) this will be your decision. The benefits and risks of the above treatment options will be discussed with you so that your decision is informed. Occasionally miscarriage can be accompanied by very heavy bleeding, necessitating blood transfusion and may pose risks to your overall health and well being. The other reason for suggesting an ERPC is if pregnancy tissue remains in the uterus (womb) this can lead to infection which occasionally can be serious.

This is when the pregnancy implants and grows outside the womb, usually in the fallopian tubes or occasionally the ovary. The symptoms usually include acute pain and slight bleeding. A scan is normally performed to assess whether this suspected diagnosis is correct. An ectopic pregnancy is a serious complication and it is not possible to save the pregnancy. Surgery is usually required but sometimes medication can resolve this. More information here by clicking on ectopic pregnancy.

The sonographers and obstetricians in Merrion Ultrasound are all highly qualified in scanning and are very experienced. You can meet some of our sonographer team here.