Early pregnancy assessment

Ultrasound (cont.)
With the introduction of transvaginal scanning, we removed the sight of distraught women with full bladders waiting for a transabdominal scan, which would often produce inconclusive results. Now women are able to have a scan immediately, which produces a conclusive result in 95% of cases. The majority of women (65 -70%) who present with and bleeding in early pregnancy will have an ongoing viable intrauterine pregnancy. Approximately 20-25% will have signs of a complete, incomplete or missed miscarriage. 1-2% will have clear signs that there is an etopic pregnancy (positive pregnancy test, empty uterus, abundant free fluid in the pelvis or occasionally, the ectopic pregnancy visualized in the tube). In about 5% of scans the diagnosis will be unclear. In these circumstances serum HCG level is obtained (2-3 hours).

HCG
Human chorionic gonadotrophin (HCG) is a hormone produced by the placenta (afterbirth) of a pregnancy. The levels of HCG rise very quickly in early pregnancy. It is usually possible to see a pregnancy sac in the womb when the level of HCG is > 2500 i.u. If there is no sac a laparoscopy is usually performed to investigate the possibility of an ectopic pregnancy. If the HCG <2000 i.u., and there is clinical suspicion that the pregnancy is ectopic, the patient may have a laparoscopy. (Continued next page)