Pregnancy can cause additional kidney strain in people with chronic kidney disease (CKD). Pregnant people with advanced CKD may have a higher risk of health complications, such as preeclampsia and anemia.

Someone with CKD experiences a gradual loss of kidney function, which can eventually lead to kidney failure. CKD in a pregnant person may also increase the risk of preterm birth and can affect the health of the unborn baby.

Pregnancy may cause CKD to progress more rapidly, and a person may require treatment such as dialysis or a kidney transplant sooner than if they had not been pregnant.

A pregnant person sitting in a doctor's office and speaking with a nurse about kidney disease.-2Share on Pinterest
SDI Productions/Getty Images

The kidneys remove various waste products from the body, such as uric acid, and expel them in the urine. The organs also reabsorb nutrients from the blood, release essential compounds, and help regulate blood pressure.

During pregnancy, blood flow to the kidneys increases, and the glomerular filtration rate (GFR) can increase by 50%. GFR refers to the amount of blood the kidneys can filter each minute.

The increase in blood flow and GFR during pregnancy can strain the kidneys and cause them to work harder than usual. This can affect how they function.

Pregnancy may not lead to complications in people with early stage CKD, depending on their overall health.

However, the additional strain on the kidneys may cause severe complications in pregnant people with advanced CKD from stages 3 to 5.

A pregnant person with advanced CKD may be more likely to experience complications if they have:

  • a later stage of kidney disease
  • high blood pressure
  • proteinuria, in which protein leaks into the urine
  • high levels of the waste product creatinine, which could indicate the kidneys are not adapting to the pregnancy

Research from 2019 also suggests that people with preeclampsia, a condition that causes blood pressure to rise suddenly during pregnancy, may have a higher risk than the larger population of developing CKD later in life.

The risk of complications from kidney disease during pregnancy is higher for people with advanced CKD. Complications may affect the pregnant person and the developing baby.

Complications for the pregnant person

Research suggests that pregnancy can cause a more rapid decline in kidney function in people with advanced CKD.

A 2019 study found that pregnant people with stage 3a CKD lost kidney function, equivalent to 1.7 years of kidney disease. Pregnant people with stages 4 to 5 CKD lost kidney function equivalent to 4.9 years of kidney disease.

Other potential complications for the pregnant person include the following:

  • Earlier treatment: According to the 2019 study, pregnant people with advanced CKD were likely to need a kidney transplant or dialysis 2.5 years earlier than if they had not been pregnant.
  • Preeclampsia: CKD increases a person’s risk of preeclampsia. Symptoms include severe headaches, pain, and vomiting. Rarely, the condition can lead to eclampsia, which can be life threatening for the pregnant person and the unborn baby.
  • Hemolysis, elevated liver enzymes and low platelets syndrome (HELLP): HELLP syndrome affects the liver, blood, and blood pressure. Without treatment, the syndrome may be severe and can complicate pregnancy.
  • Anemia: CKD may increase the risk of anemia. In people with CKD, anemia may increase the risks of cognitive impairment, hospitalization, and mortality. In pregnancy, anemia can lead to adverse fetal outcomes, including preterm birth.
  • Pregnancy loss: The 2019 study states that pregnancy loss is a risk for people at all stages of CKD, including the early stages. The risk of stillbirth for people with CKD is nine times higher than those without.

Complications for the baby

Potential complications for the unborn baby include the following:

  • Fetal growth restriction (FGR): CKD can increase the risk of FGR, which causes a baby to be born at a lower-than-average weight. Doctors associate FGR with various short and long-term complications, including:
  • Preterm delivery: CKD increases the risk of preterm delivery, which occurs before 37 weeks of pregnancy. It can lead to complications, including:
    • neurodevelopmental difficulties
    • neurological disorders
    • asthma
    • hearing loss

Pregnant people with CKD may require more frequent checkups and imaging scans in addition to their routine antenatal care.

A doctor may need to adjust a person’s CKD treatment during pregnancy, as some medications may be harmful to the unborn baby’s development. They may swap certain medications for safer alternatives and monitor the pregnant person’s kidney function and blood pressure closely.

A pregnant person with CKD will require treatment and monitoring for their blood pressure, as they are at higher risk of preeclampsia. To reduce this risk, a doctor may suggest a person take low dose aspirin and their prescribed blood pressure medication.

A pregnant person with CKD may also require iron, which a doctor can administer through injection and vitamin D.

A healthy diet may also help a person manage CKD. A doctor may advise a person with kidney disease to avoid foods high in phosphate and potassium and to eat a balance of:

  • fruits and vegetables
  • healthful protein sources, such as meats, pulses, or beans
  • healthful starchy foods, such as wholegrain rice, bread, or pasta
  • some dairy or dairy alternatives
  • limited salt, sugar, and saturated fats

Learn what foods to avoid with CKD.

A person should contact a doctor if they have symptoms of CKD, as early treatment can help prevent symptoms from worsening.

People may not have symptoms during the early stages of CDK. Late stage symptoms may include:

If a person has CKD and becomes pregnant, they should contact a doctor.

A doctor may need to adjust treatment for the safety of the unborn baby. Pregnancy also increases the risk of various complications in people with CKD, which require monitoring and treatment.

Can pregnancy cause kidney problems?

Pregnancy can place additional strain on the kidneys, which can worsen existing kidney problems.

Is pregnancy safe with one kidney?

Pregnant people with one kidney are at higher risk of various complications, including high blood pressure, preeclampsia, and adverse fetal complications.

Can someone have dialysis while pregnant?

A person can have dialysis while pregnant. However, dialysis during pregnancy significantly increases a person’s risk of health complications.

Dialysis is a procedure that often involves diverting blood to a machine to remove waste and excess fluid. A person may require regular dialysis if their kidneys cannot function properly.

There is an association between chronic kidney disease (CKD) during pregnancy and various health complications for the pregnant person and the unborn baby. These include a more rapid decline in kidney function, preeclampsia, and preterm delivery.

The risks of complications during pregnancy are higher for people with advanced stages of CKD. A person with CKD may require extra care in addition to their typical antenatal treatment.

A person should consult a doctor on treatment options for CKD during pregnancy. A person with CKD can also discuss the risks of pregnancy with a doctor before conceiving and the steps they could take to help manage them.