What does it mean if I have protein in my urine?

Testing for protein in your urine (proteinuria) is a routine test that your caregiver will do at your first antenatal appointment, and may do at subsequent appointments if you have risk factors for certain conditions.

Having small amounts of protein in your urine is common in pregnancy. It can happen for a number of reasons. It probably just means that your kidneys are working harder now that you’re pregnant.

Protein in your urine could also mean that your body is fighting a minor infection, especially if your blood pressure is normal. Your caregiver may send your sample for analysis to check if you have a urinary tract infection (UTI). If you have a UTI, your doctor or midwife will prescribe an antibiotic that’s safe to take in pregnancy.

Your caregiver will add your proteinuria levels to your maternity notes. He’ll note down whether you have the lowest amount, called a trace level, or more, which is marked with a +, ++ or +++, depending on how much protein is present. Ask your caregiver to explain the result if you’re not sure what it means for you.

Depending on the proteinuria level, your caregiver may bring forward your next antenatal appointment. He’ll check again to see if there’s still protein present, and whether the amount has increased.

Your caregiver will be especially vigilant about protein in your urine if you’re in the second half of your pregnancy, as it may be a sign that you are developing pre-eclampsia, a potentially serious condition.

Pre-eclampsia is thought to be caused by the placenta not working properly. It can increase your blood pressure and affect how well your kidneys filter your blood. Protein in your urine alongside high blood pressure can be a sign of pre-eclampsia.

If your urine sample contains high levels of protein, and your blood pressure is raised, your caregiver may take a blood sample. This will check your blood count, clotting, and kidney and liver function.

If your midwife or doctor is concerned about your proteinuria levels, or any other symptoms you have, he may send you straight to your local maternity unit for more tests. You should get the results within four hours.

If the proteinuria is found to be at safe levels, you’ll be able to go home again. But if there are still concerns, you’ll need to stay for further monitoring.

Keep an eye out for other symptoms of pre-eclampsia from mid-pregnancy onwards, including:

• severe headache
• problems with your vision, such as blurring or flashing before your eyes
• severe pain just below your ribs
• vomiting
• sudden, severe swelling of your hands, feet or face

These symptoms can come on quickly. Call your doctor, midwife or maternity unit immediately if you notice any of them. This is especially the case in the second half of your pregnancy, or in the first few days after giving birth.

Learn more about pre-eclampsia.

Reviewed for BabyCenter Australia by Hannah Dahlen, midwife