Posted: Fri Apr 06, 2007 12:07 pm Post subject: PRECOG 3 - who needs early specialist input?
So who will be offered specialist input and why? The PRECOG guideline lists people with previous pre-clampsia (any type, any level of severity), people with high blood pressure (hypertension or a booking diastolic blood pressure of 90mmHg or more), people with kidney disease, diabetes, antiphospholid antibodies, and people who are expecting twins.
All of these people will benefit from seeing a specialist early in their pregnancy, to give extra advice on your antenatal care. Which specialist you go and see will depend on the risk factor that you have.
If you have had pre-eclampsia before, it can be really helpful to see a specialist who knows something about pre-eclampsia. Many women go even before they have conceived, to help understand what happened to them before and why. The whole point of this, apart from making you feel better, is to see if you as an individual would benefit from treatment in your next pregnancy. The two main treatments are low dose aspirin and heparin - both of which basically make your blood less sticky, but in different ways - and both of which can help slow down or stop the blood vessels in your placenta blocking up, which is the start of the pre-eclampsia process. It is not suitable for everyone, so dont worry if you are not offered these. But if you are going to take them, you may well start taking them really early on in pregnancy.
As well as this the consultant may advise how often you should be seen to have your blood pressure and proteinuria checked. Depending on what happened to you before, you may be invited to have different types of ultrasound scans (Doppler scans look at the flow of blood in your blood vessels, growth scans look at the baby and the fluid around the baby and measure how they change) and blood tests. Most of these will kick in after 20 weeks - for almost everyone this is the earliest time that the effects of pre-eclampsia can be seen either in the baby or the mother.
So what schedule might the specialist advise? Well, there are two basic rules of thumb. The first is that, if you have had pre-eclampsia before and get it again, it is likely to start about the same time or up to four weeks later than the first time. The second rule of thumb is that it takes an average of 2 weeks from getting the high blood pressure and proteinuria of pre-eclampsia to being in a situation where your baby may need to be delivered. Although this is an average (which means it could be 1 day or it could be many weeks) the PRECOG guideline uses this 2 week rule to say how often you should have your blood pressure and urine checked. If you have had pre-eclampsia before you should be seen as an absolute minimum every 2 weeks.
If you have kidney (renal) disease or diabetes the specialist that you will see will be a specialist in those conditions and will develop an individual antenatal care plan for you.
If you are expecting twins or more babies you will be offered consultant care - often in a clinic for women with twins - and your obstetrician will include the fact that you are more likely to get pre-eclampsia when deciding how often you should be seen.
Finally, if you know that you have hypertension before you are pregnant a specialist will be able to advice you on the best management of your high blood pressure. As your body adapts to being pregnant everyone's blood pressure naturally falls (until about 16 weeks) then increases again. So about the time that you first see your midwife (booking) everyone's blood pressure will be at its lowest. If at this time the diastolic blood pressure is 90mmHg or more (the lowest of the two numbers) you will need specialist care to manage your blood pressure throughout pregnancy, even if you didnt know you had hypertension before you were pregnant.