What are the complications and management strategies for Chronic Kidney Disease (CKD) patients during pregnancy?

Complications and Management of CKD in Pregnancy

Pregnant women with chronic kidney disease (CKD) face significantly higher risks of adverse maternal, fetal, and obstetric outcomes, with only 21% of pregnancies being uncomplicated. 1, 2

Maternal Complications

• Worsening renal function: Women with incipient renal failure (serum creatinine ≥3 mg/dl or creatinine clearance <50 ml/min) have a 40% risk of permanent worsening of renal function during pregnancy 3, 1
• Superimposed preeclampsia: CKD patients have significantly higher rates of preeclampsia (40-60%) compared to the general population 3, 4
• Accelerated hypertension: Pregnancy-induced physiological changes can worsen pre-existing hypertension in CKD patients 3, 5
• Anemia: Physiologic anemia of pregnancy can be exacerbated in CKD patients 1
• Urinary tract infections: Increased risk of pyelonephritis due to pregnancy-related urinary stasis 1

Fetal/Neonatal Complications

• Preterm delivery: 54-86% of CKD pregnancies result in preterm delivery (<37 weeks), with rates increasing with CKD severity 4, 6
• Small for gestational age (SGA): 27-64% of infants born to mothers with CKD are SGA 4
• Fetal growth restriction: Impaired placental perfusion due to maternal hypertension and vascular disease 3
• Increased perinatal mortality: 5-14% risk depending on CKD severity 4

Risk Stratification

Risk assessment should be performed before conception and should consider:

• CKD stage/severity: Moderate to severe CKD (serum creatinine >125 μmol/L) is associated with worse outcomes 4, 6
• Degree of proteinuria: Proteinuria >190 mg/day before conception increases risk of preeclampsia 3
• Hypertension control: Pre-existing hypertension increases risk of adverse outcomes 3, 5
• Comorbidities: Diabetes and other vascular diseases further increase risks 2

Management Strategies

Preconception Care

• Multidisciplinary approach: Care should be coordinated between nephrology, maternal-fetal medicine, and obstetrics 1, 2
• Medication review: Discontinue teratogenic medications (ACE inhibitors, ARBs) prior to conception 1
• Baseline assessment: Evaluate renal function, proteinuria, and blood pressure before conception 3, 1
• Risk counseling: Provide individualized counseling regarding maternal and fetal risks based on CKD stage 2, 6

Blood Pressure Management

• Target BP: Maintain blood pressure between 110-140/85 mmHg 3, 1
• First-line agents: Methyldopa, labetalol, and long-acting nifedipine are preferred antihypertensives 1, 7
• Urgent treatment: BP ≥160/110 mmHg requires immediate treatment in a monitored setting with oral nifedipine, IV labetalol, or hydralazine 3, 7
• Home monitoring: Weekly home BP monitoring is recommended for all CKD patients 1, 7

Renal Function Monitoring

• Regular assessment: Monitor serum creatinine, electrolytes, and proteinuria at least monthly 1
• Early dialysis: For progressive renal disease, early initiation of dialysis with an aggressive prescription of approximately 36 hours per week improves outcomes 3, 1
• Post-delivery follow-up: Early postpartum visit (within 7-10 days) for BP check and renal function assessment 2

Prevention of Preeclampsia

• Low-dose aspirin: All CKD patients should receive low-dose aspirin from the first trimester until 36 weeks gestation 1, 2
• Regular screening: Monitor for signs of preeclampsia at each visit (proteinuria, hypertension, symptoms) 3, 7

Infection Prevention

• Urinalysis: Monthly screening for asymptomatic bacteriuria 1
• Prompt treatment: Treat symptomatic UTIs with appropriate antibiotics 1

Delivery Planning

• Timing: Based on maternal and fetal status; earlier delivery may be necessary if maternal condition deteriorates 1
• Steroids: Administer if delivery anticipated before 34 weeks to accelerate fetal lung maturation 1
• Mode of delivery: Determined by obstetric indications rather than CKD status 2

Special Considerations

• Dialysis patients: Intensify dialysis regimen to approximately 36 hours per week 3, 1
• Transplant recipients: Maintain stable immunosuppression with pregnancy-compatible medications 2
• Diabetic nephropathy: Additional monitoring for gestational diabetes and diabetic complications 3

Postpartum Care

• Close monitoring: Continue BP and renal function monitoring for at least 6 weeks postpartum 1, 2
• Medication adjustment: Safe resumption of pre-pregnancy medications as needed 2
• Breastfeeding: Generally safe and recommended for most women with CKD 2
• Contraception planning: Implement effective contraception based on patient preferences and medical eligibility 2

Common Pitfalls to Avoid

• Delayed nephrology referral: Early involvement of nephrology is crucial 2
• Inadequate BP control: Failure to treat hypertension aggressively enough increases risk of preeclampsia 8, 5
• Overlooking proteinuria: New-onset or worsening proteinuria may indicate superimposed preeclampsia 7
• Insufficient monitoring: Pregnancy in CKD patients requires more frequent monitoring than normal pregnancies 1, 6
• Inappropriate medication use: Continuing teratogenic medications during pregnancy 1