Pregnancy Ultrasound: Early Pregnancy Assessment FAQs

Pregnancy Ultrasound

Q: Will I need to drink lots of water and have a full bladder for my appointment?
A: No - an empty bladder makes the examination easier for us.

Q: What do you mean by 'transvaginal ultrasound'?
A: Ultrasound works by sending out sound waves at a target (in this case your womb) and then analysing the pattern produced by the echoes that are bounced back. You will probably be familiar with scans carried out during pregnancy - these are performed by passing a probe over the stomach.

These often require the bladder to be very full. In early pregnancy or when scanning for gynaecological problems it is better to place the probe in the vaginal closer to the area of interest. In this way clearer images can be obtained (and for example in pregnancy the heartbeat of the embryo can be seen at least a week earlier).

The vaginal probe is about the size of a tampon and for most women the examination is not uncomfortable. If it is the examination will be stopped. A further advantage of this approach is that the bladder does not need to be full which should make both waiting and the examination more comfortable.

Q: What do they do to the probe between examinations?
A: During the examination the probe is covered with a thick latex sheath rather like a condom. Between scans the probe is cleaned with an alcohol based cleaner.

Q: What is the point of the blood test?
A: The blood test measures the level of a hormone called HCG in the bloodstream. This hormone is produced from the outset of a pregnancy. We know what the level of this hormone should be for any particular stage of an early pregnancy and also the rate at which it should rise or fall. This is useful in diagnosing either en ectopic pregnancy or a failing pregnancy.