Supplementary Material for: A Systematic Review and Meta-Analysis of Kidney and Pregnancy Outcomes in IgA Nephropathy

<i>Background:</i> The outcomes of pregnancy in immunoglobulin A nephropathy (IgAN) remain controversial. We sought to evaluate the effect of pregnancy on the progression of IgAN as well as the impact of IgAN on pregnancy outcomes. <i>Methods:</i>We systematically searched MEDLINE, Embase for cohort or case-control studies. OR reductions were calculated with a random-effects model, and kidney outcomes and adverse pregnancy events were analyzed. <i>Results:</i> Our literature search returned 652 relevant articles; 4 studies were included, providing data of 376 pregnancies in 273 patients with IgAN and that of 241 IgAN who did not become pregnant. Four hundred sixty seven patients with chronic kidney disease stages 1-2 were included. Pregnancy in patients with IgAN did not increase the risk of adverse renal events including doubling of serum creatinine, 50% decline in glomerular filtration rate (GFR) and end-stage kidney disease (OR 0.97, 95% CI 0.55-1.70; p = 0.90; I2 = 0.0%, p = 0.79). There was no significant difference in the change in estimated GFR at the end of follow-up in the pregnant and non-pregnant groups (weighted mean difference 0.1 ml/min/1.73 m2 (95% CI -4.85 to 5.04 ml/min/1.73 m2), p = 0.97; I2 = 0%, p = 0.95). Women with IgAN had high rates of infant loss (12.2, 7.4-19.4%), preterm delivery (8.5, 5.9-12.1%), low birth weight (9.5, 6.7-13.3%), and preeclampsia/severe preeclampsia (7.3, 4.9-10.6%). <i>Conclusions:</i> Pregnancy in IgAN patients with preserved kidney function did not accelerate deterioration of renal function. But pregnant women with IgAN are at higher risk of pregnancy complications.