Membranous Nephropathy in Pregnancy

Am J Nephrol. 2020;51(4):304-317. doi: 10.1159/000505175. Epub 2020 Feb 25.

Abstract

Background: Primary membranous nephropathy (pMN) is less common in women of child-bearing age. The kidney risk factors to adverse maternal-fetal outcomes and the effects of pregnancy on pMN process need to be investigated.

Methods: We retrospectively screened all the patients with biopsy-proven pMN from 2008 to 2018. Any cases of pregnancy that occurred at the time of pMN diagnosis or during follow-up were included in the study. Clinical and pathological data were collected from all patients at the time of kidney biopsy and their gestational results were recorded.

Results: Of the 27 pregnancies with gestational time of 35.9 ± 4.5 weeks, 10 adverse maternal-fetal events occurred, including fetal loss (11%), preterm delivery (26%), and severe preeclampsia (15%). The kidney parameters were relatively stable with all preserved kidney function. Time-averaged urinary protein (p < 0.001) and serum albumin (p < 0.001), maximum urinary protein (p = 0.001) and minimum serum albumin (p = 0.01) before week 20, anti-phospholipase A2 receptor (PLA2R) positivity (p = 0.03), and no remission during pregnancy (p = 0.004) were risk factors to adverse maternal-fetal outcomes. Time-averaged urinary protein and serum albumin correlated with the birth weight percentile of neonates.

Conclusions: Pregnancy in pMN patients showed risks to adverse maternal-fetal events. Heavy proteinuria, especially before week 20 of gestation, severe hypoalbuminemia, positive anti-PLA2R, and no remission were risk factors to worse outcomes.

Keywords: Membranous nephropathy; Outcomes; Phospholipase A2 receptor; Pregnancy; Risk factor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Autoantibodies / blood*
  • Autoantibodies / immunology
  • Biopsy
  • Birth Weight / immunology
  • Female
  • Fetal Death*
  • Glomerular Basement Membrane / immunology
  • Glomerular Basement Membrane / pathology
  • Glomerular Basement Membrane / ultrastructure
  • Glomerulonephritis, Membranous / blood
  • Glomerulonephritis, Membranous / complications*
  • Glomerulonephritis, Membranous / diagnosis
  • Glomerulonephritis, Membranous / immunology
  • Humans
  • Microscopy, Electron
  • Pre-Eclampsia / blood
  • Pre-Eclampsia / epidemiology*
  • Pre-Eclampsia / immunology
  • Pre-Eclampsia / urine
  • Pregnancy
  • Premature Birth / blood
  • Premature Birth / epidemiology*
  • Premature Birth / immunology
  • Premature Birth / urine
  • Receptors, Phospholipase A2 / immunology
  • Retrospective Studies
  • Risk Factors
  • Serum Albumin, Human / analysis

Substances

  • Autoantibodies
  • PLA2R1 protein, human
  • Receptors, Phospholipase A2
  • Serum Albumin, Human