Kidney Stones During Pregnancy: Essential Facts & Safe Treatments

Oct, 1 2025

Quick Take

• Pregnancy can increase the chance of developing kidney stones because of hormonal changes and urinary shifts.
• Most imaging is done with ultrasound to avoid radiation.
• Conservative treatment-hydration, pain control, and close monitoring-is the first line.
• Procedures such as ureteroscopy are safe when needed, but shock wave lithotripsy is avoided.
• Preventive steps include drinking plenty of water, balancing calcium intake, and limiting high‑oxalate foods.

Understanding Kidney stones is a hard mineral deposit that forms in the kidneys and can travel down the urinary tract, causing pain and blockage

When a stone gets stuck, the body reacts with intense flank pain, nausea, and sometimes blood in the urine. For most non‑pregnant adults, the typical approach involves pain medication, hydration, and, if the stone is large, a procedure to break it up or remove it.

During pregnancy, the stakes shift. The growing uterus compresses the ureters, slowing urine flow and creating a perfect environment for stones to form. Hormones like progesterone relax smooth muscle, further reducing urinary clearance.

How Pregnancy is the condition of carrying a developing fetus in the uterus, marked by hormonal and anatomical changes that affect many body systems changes stone risk and symptoms

Two main factors raise the risk:

1. Urinary stasis: The uterus presses on the ureters, especially on the right side, causing urine to pool.
2. Metabolic shifts: Increased calcium excretion and altered citrate levels make stone‑forming minerals more likely to crystallize.

Because the pain of a kidney stone can mimic typical pregnancy discomfort, many women dismiss early signs. However, a sudden, sharp pain that radiates to the groin, especially with blood‑tinged urine, should raise a red flag.

Diagnosing Stones Safely

The first step is a urinalysis to check for blood, crystals, and infection. Blood tests can reveal elevated calcium or uric acid, but they are not definitive.

Imaging is where caution matters most. Ultrasound imaging uses sound waves to create a picture of the kidneys and urinary tract without ionizing radiation is the gold standard. It can detect the stone’s size, location, and any hydronephrosis (swelling of the kidney due to urine backup).

If ultrasound is inconclusive and the stone is causing severe obstruction, a low‑dose CT scan can be employed with shielding to limit fetal exposure, but it is reserved for emergencies. MRI is another radiation‑free alternative, though it is less sensitive for calcifications.

Treatment Options That Are Safe for Expectant Moms

Most cases resolve with conservative measures:

• Hydration increasing fluid intake to produce at least 2 liters of urine daily, which helps flush out small stones reduces stone size and eases passage.
• Pain management typically involves acetaminophen; opioids are used sparingly and under obstetric guidance keeps the mother comfortable while avoiding fetal risk.
• Medical expulsive therapy uses medications like tamsulosin to relax ureter muscles; however, it is generally avoided in pregnancy due to limited safety data.

If the stone is larger than 5mm, does not move, or causes infection, a minimally invasive procedure is considered.

Ureteroscopy, often combined with a tiny laser fiber, can break the stone into dust that passes naturally. Studies up to 2024 show success rates above 90% with no increase in preterm labor when performed by an experienced team.

Red‑Flag Situations: When to Call for Help

If you notice any of the following, seek emergency care immediately:

• Fever over 38°C (100.4°F) or chills-signs of infection.
• Severe, uncontrolled pain despite medication.
• Sudden decrease in fetal movements.
• Persistent vomiting that prevents fluid intake.
• Blood pressure spikes, which could indicate preeclampsia triggered by infection.

Emergency teams will prioritize maternal stabilization, start IV fluids, give safe antibiotics if infection is suspected, and arrange rapid imaging.

Preventing Stones While Expecting

Prevention is a daily habit rather than a single fix.

• Stay hydrated: Carry a refillable bottle, sip water every 15‑20 minutes, and aim for clear‑yellow urine.
• Balance calcium: Don’t cut calcium outright; instead, get 1,000mg/day from dairy or fortified alternatives to bind oxalate in the gut.
• Limit oxalate‑rich foods: Reduce intake of spinach, rhubarb, nuts, and beetroot, especially when eaten in large portions.
• Watch sodium: High salt increases calcium excretion-keep sodium under 2,300mg/day.
• Get enough citrate: Citrus fruits (lemon, orange) raise urinary citrate, which helps prevent stone formation.

Consult your Obstetrician a medical doctor specializing in pregnancy and childbirth, who coordinates care with other specialists when needed before making any major diet changes or adding supplements.