Pregnancy Raises the Risk for Kidney Stones

Kidney stones can happen to anyone, but now a new study confirms that being pregnant may increase your risk of developing them.

Previous research has suggested that a number of pregnancy-related changes in the body can contribute to kidney stone formation, but this study is the first to provide evidence of that link, according to the researchers.

For the study, the Mayo Clinic team reviewed the medical records of nearly 3,000 women from 1984 to 2012, including 945 who had a first-time symptomatic kidney stone and a control group of 1,890 age-matched women.

The researchers concluded that pregnancy increases the risk of a first-time symptomatic kidney stone, and that the risk is highest close to delivery and then declines by one year after delivery.

However, a slight risk persists beyond one year after delivery, according to the study published April 15 in the American Journal of Kidney Diseases.

Symptomatic kidney stones are the most common non-obstetric reason for hospital admission among pregnant women, the study authors noted. They occur in one of every 250 to 1,500 pregnancies, most often during the second and third trimesters.

“We suspected the risk of a kidney stone event would be high during pregnancy, but we were surprised that the risk remained high for up to a year after delivery,” said nephrologist and senior study author Dr. Andrew Rule.

“There also remains a slightly increased risk of a kidney stone event beyond a year after delivery. This finding implies that while most kidney stones that form during pregnancy are detected early by painful passage, some may remain stable in the kidney undetected for a longer period before dislodging and resulting in a painful passage,” Rule explained in a Mayo Clinic news release.

In pregnancy, kidney stones can cause significant complications, ranging from preeclampsia and urinary tract infections to preterm labor/delivery and pregnancy loss. And diagnosis and treatment of kidney stones during pregnancy can be challenging, Rule said.

According to nephrologist and study corresponding author Dr. Charat Thongprayoon, “During pregnancy, a kidney stone may contribute to serious complication, and the results of this study indicate that prenatal counseling regarding kidney stones may be warranted, especially for women with other risk factors for kidney stones, such as obesity.”

General recommendations for preventing kidney stones include high fluid intake and a low-salt diet. Mayo Clinic experts also recommend that pregnant women get at least 1,000 milligrams of calcium a day, preferably from food sources such as dairy products rather than calcium supplements.

More information

The National Kidney Foundation has more on kidney stones.

SOURCE: Mayo Clinic, news release, April 15, 2021

Source: HealthDay