Jennifer Yo discusses increased risk of kidney damage following preeclampsia

Women who experience preeclampsia face a higher risk of developing early laboratory signs of chronic kidney disease (CKD) in the years following pregnancy, according to a large population-based cohort study published in the Journal of the American Society of Nephrology. Despite the elevated risk, postpartum kidney monitoring rates were low.

Preeclampsia, a systemic hypertensive disorder of pregnancy, has long been associated with an increased risk of kidney failure later in life. However, kidney failure can take decades to develop, and the relationship between preeclampsia and earlier, potentially modifiable stages of kidney disease has remained less clear. Investigators conducted a population-based cohort study in Stockholm, Sweden, including all nulliparous women who had at least one pregnancy ending in live or stillbirth between January 1, 2006, and December 31, 2020.

Women with preexisting hypertension, diabetes, or CKD were excluded. The primary outcomes were laboratory indicators of kidney damage: albuminuria, defined as a urine albumin-creatinine ratio greater than 300 mg/g; reduced kidney function, defined as estimated glomerular filtration rate (eGFR) below 60 ml/min per 1.73 m²; and a composite outcome of either marker.

The study included 171,693 pregnancies among 170,192 women, with a mean age of 29 years. Of these, 10,538 pregnancies (6%) were complicated by preeclampsia. Over a median follow-up of 7 years, albuminuria greater than 300 mg/g occurred after 775 pregnancies (0.5%), reduced eGFR occurred after 248 pregnancies (0.1%), and the composite outcome occurred after 985 pregnancies (0.6%). Incidence rates were consistently higher among women with a history of preeclampsia. Albuminuria occurred at a rate of 1.53 per 1000 person-years after preeclampsia compared with 0.57 per 1000 person-years without preeclampsia. Reduced eGFR occurred at rates of 0.52 versus 0.18 per 1000 person-years, respectively. The composite outcome occurred at rates of 2.00 versus 0.73 per 1000 person-years.

After weighting, preeclampsia was associated with an increased risk across all outcomes, with hazard ratios of 2.53 for albuminuria, 2.18 for reduced eGFR, and 2.43 for the composite outcome. Despite these findings, postpartum monitoring for kidney dysfunction was uncommon. Within the first year after delivery, 20% of women with preeclampsia underwent serum creatinine testing, and 10% had urine albumin testing. The authors concluded that preeclampsia was associated with a significantly increased risk of early laboratory signs of kidney damage and highlighted low rates of postpartum kidney function monitoring, suggesting potential missed opportunities for earlier identification and intervention.

For further insight, read the below written Q&A with the study’s lead author, Jennifer Yo, Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; Faculty of Medicine Nursing and Health Sciences, School of Clinical Sciences, Monash University, Melbourne, Victoria, Australia.

In the Q&A, Yo further explores the study’s findings and provides practical takeaways for ob-gyn clinicians, including guidance on postpartum kidney monitoring and implications for longer-term kidney outcomes.

Contemporary OB/GYN:

To set the stage, can you walk us through what motivated this study and how you approached evaluating kidney risk after a pregnancy complicated by preeclampsia?

Jennifer Yo:
We’ve known for some time that preeclampsia is linked to later kidney failure, but that endpoint can take decades to emerge, often after many prevention opportunities have been missed. The practical question we wanted to answer was: at what point after a pregnancy complicated by preeclampsia can we detect early signs of kidney injury using routine tests? We approached this by tracking early laboratory markers of kidney disease after pregnancy, so risk can be identified when intervention is still realistic.

Contemporary OB/GYN:

What were the main kidney outcomes you tracked, and why did you focus on early laboratory markers like albuminuria and eGFR rather than end-stage disease?

Yo:
We focused on three outcomes: albuminuria, reduced eGFR <60ml/min per 1.73m², and a composite of the two, because these represent early, measurable kidney damage. Kidney failure is an important outcome, but it typically occurs many years after pregnancy, making it less useful. In contrast, if changes in albuminuria and eGFR can be detected earlier, this will help stratify risk, and open a window to intervene through targeted risk-factor management and, kidney-protective therapies.

Contemporary OB/GYN:

How did the risks of albuminuria, reduced eGFR, and the composite outcome differ between women with and without preeclampsia?

Yo:
Women with a history of preeclampsia had a 2–3 times higher risk of albuminuria, reduced eGFR below 60 mL/min per 1.73 m2, and the composite outcome compared with women without preeclampsia.

Contemporary OB/GYN:

Were there any findings that surprised you in terms of how early kidney disease emerged after pregnancy?

Yo:
One striking finding was how early clinically important disease markers appeared. Many women developed severe albuminuria (UACR >300 mg/g) before the age of 50 years, which places them at elevated long-term risk. In our cohort, around 2% of women with prior preeclampsia developed severe albuminuria and did so at an age 10 years younger than women without preeclampsia.

Contemporary OB/GYN:

Despite the elevated risks you identified, postpartum kidney monitoring was uncommon. What do you think is driving this gap in follow-up care?

Yo:
There are several reasons. Previously, there was a lack of awareness that preeclampsia increases long-term maternal cardio-kidney-metabolic complications. Fortunately, this has improved. Another driving factor is that we don’t know which professional group(s) should be responsible for implementing routine clinical follow-up – at present, there is no standard follow-up of these women, even for cardiovascular disease, because it is unclear whose responsibility this should be. Finally, postpartum is really challenging! New mothers are balancing infant feeding and caregiving, fatigue, recovery, and logistics, and attending extra medical appointments can be difficult and easily deprioritized.

Contemporary OB/GYN:

From a practical standpoint, how should OB-GYNs and primary care clinicians think about postpartum kidney surveillance after preeclampsia?

Yo:
Practically, women should have urine albumin and serum creatinine/eGFR checked within the first postpartum year, with repeat testing guided by the results and overall risk profile. Longer term, annual testing is reasonable for women with additional risk factors such as persistent hypertension, obesity, or diabetes, or those with more severe or earlier-onset preeclampsia. The key gap is that we still need better data to define the optimal intensity of surveillance and whether it should be targeted to the highest-risk subgroups or applied more broadly.

Contemporary OB/GYN:

Based on your findings, what opportunities exist for earlier intervention that could potentially change long-term kidney outcomes for these patients?

Yo:
If albuminuria or reduced eGFR is detected, clinicians can intensify management of blood pressure and metabolic risk factors, address lifestyle factors, and consider timely referral and kidney-protective therapies where indicated. The last few years have been transformative in kidney care because we now have more effective options to slow progression than we did previously. That’s why this kind of evidence is timely: because we have a chance to meaningfully change the long-term outcomes for these women.

Reference:

Yo JH, Yuanhang Y, Caldinelli A, et al. Laboratory Signs of CKD after Preeclampsia. Journal of the American Society of Nephrology. January 2, 2026. doi: 10.1681/ASN.0000001001