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> > > > > How do blood tests help doctors to manage my pregnancy?

How do blood tests help doctors to manage my pregnancy?

When you’re pregnant you may have symptoms like tiredness and joint pain, and it can be difficult to tell whether these are due to the pregnancy or your arthritis. Blood and urine tests can help doctors to tell the two things apart, so these tests will be done regularly throughout your pregnancy, especially if you’re feeling unwell.

Some special blood tests are carried out either before you start trying to get pregnant or early in pregnancy to help your doctors decide whether you need any special treatment or monitoring. These tests are for:

Anti-Ro antibodies

These are present in about 30% of patients with lupus and also occur in Sjogren’s syndrome. If you have these there’s a small chance (about 1 in 50) that they could affect your baby. The effect could be that the baby is born with a rash that will clear up (usually within a few weeks to months) or that your baby’s heartbeat may become slow (congenital heart block).

This heart problem develops around 18 weeks into pregnancy and there are different types that may continue after the birth. Remember that even if you have anti-Ro antibodies there’s only a small chance that your baby’s heart will be affected, but your doctor will carefully monitor your baby’s heartbeat during the pregnancy. Some babies affected in this way may need to have a heart pacemaking device inserted after birth, but most will do very well.

Babies who are affected by anti-Ro antibodies from their mother are said to have the neonatal lupus syndrome. This doesn’t mean that they’ll get lupus when they’re adults, but if you’ve had one baby with this syndrome then your chances of having the same problem in future pregnancies are higher. You should discuss future pregnancy plans carefully with your lupus specialist.

Antiphospholipid antibodies

These antibodies are present in 20–30% of patients with lupus. They’re also found in patients with antiphospholipid syndrome (APS). There are two main tests for these antibodies:

  • anticardiolipin test
  • lupus anticoagulant test.

Usually both tests are done. If either or both is positive then you have antiphospholipid antibodies in your blood.

In many people antiphospholipid antibodies don’t cause any problems, but in some people they can increase the chance of miscarriage or slowing the baby’s growth in the womb.

If you’re a pregnant woman with antiphospholipid antibodies you’ll usually see a consultant with expertise in high-risk pregnancies. You’ll be given a low-dose aspirin tablet to take every day, but you may also need daily injections (which you can give yourself) of a blood-thinning drug (anticoagulant) called heparin. This drug doesn’t cross the placenta so it won’t affect your baby.


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