A study has revealed that pregnancy carries an increased risk for developing a first-time symptomatic kidney stone, which is the highest close to delivery and then reduced by the first year postpartum, although a modest risk increase is retained beyond 1 year.
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Photo: Pregnancy Carries an Increased Kidney Stone Risk | InStyleHealth |
The population-based study looked at women residing in
Olmsted County, MN, US. There was a total of 945 first-time symptomatic kidney
stone formers aged 15-45 years old and 1,890 age-matched controls participated
in the study. Index date was defined as the date of onset of a symptomatic
kidney stone for both the case and matched controls.
Comparing with those who were not pregnant, women in
their first trimester of pregnancy were not at higher risk of developing a
symptomatic kidney stone. However, the risk increased by twofold during the second
trimester and further by 2.7 times during the third trimester.
Notably, the risk increased peaked at 0 to 3 months
after delivery prior returning to baseline by 1 year after delivery.
Observed correlations persisted despite controlling
for confounding factors, such as age and ethnicity, diabetes mellitus, hypertension,
and obesity. Age, ethnicity, time, period, or number of prior pregnancies had a
null effect on the risk of a first-time symptomatic kidney stone.
On the other hand, having a prior pregnancy was also
correlated with a first-time symptomatic kidney stone.
Study, however, was limited by its observational
design and the inclusion of a predominantly white population. More so, the
exact timing of stone formation could not be determined.
Source: Am J Kidney Dis 2021;doi:10.1053/j.ajkd.2021.01.008