Kidney stones are a painful condition for a relatively normal person. It is one of the most common causes of abdominal pain. The incidence of kidney stones is 5-15% of the world population. About 50% of cases show recurrence. The trouble becomes two fold for a pregnant woman having kidney stones.
Although kidney stone formation during pregnancy is a rare occurrence, kidney stones may pose a potential risk to the health of the pregnant woman and her child. The chances of having trouble during delivery also cannot be ignored. About 1 in 1500 pregnant women are known to have kidney stones.
Pregnancy and delivery are crucial for any woman. Any risk to health during this phase can bring out adverse outcomes.
Research Studies Conducted to Assess Kidney Stones in Pregnancy Show
- Kidney stones are associated with increased morbidity and mortality among pregnant women.
- Kidney stones during pregnancy are often seen in women who have had multiple pregnancies.
- Ureteric stones are more common than kidney stones.
- About a quarter of patients give a past history of kidney stones.
- Kidney stones are commonly detected during the third trimester of pregnancy.
- Pregnant women with kidney stones are more likely to have a history of hypertension and renal diseases.
- Kidney stones during pregnancy pose an increased risk of miscarriage, preeclampsia, gestational diabetes mellitus and C-section deliveries.
- About 5-40% of cases reported pre-term deliveries.
How Are Kidney Stones Formed?
Plenty of hereditary, dietary and environmental factors may singly or in combination cause formation of kidney stones.
- Inadequate water or fluid intake
- A strong family history of kidney stones – increases risk three-folds
- Too much of calcium intake
- Urinary Tract Infections
- Vitamin A deficiency
- Immobilization for long durations
- Deficiency of urinary glycoproteins (prevent the formation of kidney stones)
- A history of hypertension
- A past history or recurrence of gout
- Anatomical abnormalities of the urinary tract can predispose to formation of kidney stones.
- Certain drugs like diuretics, protease inhibitors, and anticonvulsants can increase the risk of stone disease.
About 80% of kidney stones among the general population and during pregnancy are calcium stones. The normal population has a greater percentage of calcium oxalate stones whereas pregnant women have calcium phosphate stones.
What Causes Kidney Stones During Pregnancy?
During pregnancy, the body undergoes several changes to provide a favorable nourishing environment to the developing fetus. Some normal bodily changes can occasionally be troublesome. The following physiological changes increase the risk of kidney stone formation during pregnancy
- The kidneys have a rich pelvis and calyx system. This pelvi-calyceal system and ureters enlarge during pregnancy.
- The hormone progesterone relaxes the smooth muscles of the ureter and reduces its peristalsis.
- The pH of urine is high or alkaline during pregnancy.
- In the third trimester of pregnancy, the enlarged, pregnant uterus compresses the ureter.
- In about 90% of pregnant women, hydro-nephrosis (excessive accumulation of fluid in kidneys due to compressed ureter) can be noticed.
- Glomerular Filtration Rate (GFR) increases by about 50% during pregnancy.
- Increased GFR causes increased urinary excretion of stone forming agents like calcium, sodium, oxalate and uric acid.
- Urine stasis due to hydronephrosis along with all these physiological changes can lead to the formation of kidney stones during pregnancy.
What Are Symptoms of Kidney Stones During Pregnancy
Kidney stones are commonly formed after the second trimester of pregnancy. It is a rare occurrence for kidney stones to occur during the first trimester.
- Episodic flank region pain or in the region above the stone.
- The pain may radiate to the groin on the corresponding side.
- Nausea and vomiting are commonly present.
- Hematuria is present in about 75-95% of pregnant women with kidney stones.
- Increased frequency of urination and pain urination are common features of kidney stones in pregnant women.
- Pain due to kidney stones often presents as labor pain or uterine contractions.
- Fever with chills may be present if associated with infection.
Kidney Stones are Diagnosed Using
- An elaborate case history generally points to a diagnosis.
- Ultrasound of abdomen for kidney, ureter, and bladder
- X-ray for kidney ureter bladder is diagnostic in about 75% of cases
- CT scan for a renal system is considered the gold standard for diagnosis of kidney stones.
- Intravenous urography is considered equally important to CT scan.
- MRI is rarely used to detect and diagnose kidney stones
Radiation dose needs to be adjusted according to the condition of pregnancy and radiation time needs to be minimal. Radiation can hamper the growth of the fetus and result in deformities.
How to Treat Kidney Stones During Pregnancy?
Management of kidney stones during pregnancy is primarily conservative medical management. Surgical intervention is rarely required.
A kidney stone of size less than 5mm pass spontaneously in about 85% cases of kidney stones during pregnancy. About 50% of stones are reported to pass after delivery.
Conservative Management Includes
- Management of pain
- Maintain adequate hydration
- Antibiotics if an infection is suspected
- NSAIDs are generally avoided due to possible risk to the kidney of the unborn baby.
In case of excessive vomiting, bloody urine, and increasing infection, active surgical intervention may be required with the involvement of urologist, obstetrician, neonatologist, anesthetist, and radiologist.
Surgical Interventions for Kidney Stones are
- Insertion of a double J-stent.
- Ureteroscopic Stone Removal (URS) – This is a more frequently used and a relatively safer option for surgical management of kidney stones during pregnancy.
- Extra Corporeal Shock Wave Lithotripsy (ESWL) – This method of high ultrasound waves for fragmenting kidney stones is highly contraindicated during pregnancy due to its harmful effect upon the unborn child and even death.
- Percutaneous Nephrolithotomy (PCNL) – Minimally invasive lithotripsy or laser to fragment the stone is done. There are very few successful reported cases of PCNL done during pregnancy.
Natural Remedies For Kidney Stones During Pregnancy
There are a wide variety of options to treat kidney stones naturally during pregnancy. Since medical and surgical options can sound potentially scary, natural remedies can effectively solve your kidney stone problems without any side effects and without harming the unborn baby.
Some Measures taken Routinely can Prevent Formation of Stones and can also Treat Kidney Stones During Pregnancy Naturally:
- Maintain adequate water/ fluid intake of about 2-3 liter/ day. Water dilutes substances in urine and also flushes out toxins from the body.
- Limit intake of animal proteins or meat. This reduces production of metabolic acids and acid-induced calcium excretion.
- Limit intake of food rich in oxalates – Spinach, soya milk, chocolates, and nuts.
- Cranberry Juice – Reduces excretion of oxalate and phosphate.
- Reduce intake of dietary salt. Avoid canned food, cheese, salted snacks, smoked and pickled food.
- Increase intake of food rich in citrates like lemon and oranges. Citrates prevent stone formation.
- Limit intake of alcohol, aerated drinks, and excess of tea and coffee.
- Do not stop all calcium intakes. Less calcium in the diet means excess oxalate will be absorbed and excreted in urine.
- Apple Cider Vinegar – 2-3 teaspoon in a glass of water can be had 2-3 times in a day. ACV helps in alkalinizing urine.
- Homeopathic and Ayurvedic modes of therapy are relatively more natural and holistic methods of managing kidney stones during pregnancy. They help in fragmenting the stone naturally and also prevent their recurrence.
Medically Reviewed By
Dr. Himanshi is a Homoeopathic consultant and currently working as a lecturer in Post-graduate faculty of Homeopathy, Parul University, Vadodara. Completed BHMS and MD in Homeopathy in January 2018 and also has a clinical experience of about 6 years. Personal interests include reading, spending time with family and traveling.