Maternal and fetal outcomes in pregnancy complicated by pre-existing lupus nephritis: Insights from a developing country Pakistan

Lupus. 2024 Apr 9:9612033241246642. doi: 10.1177/09612033241246642. Online ahead of print.

Abstract

Background: Pregnancy in women with systemic lupus erythematosus (SLE) has remained a great challenge for clinicians in terms of maternal and fetal outcomes. The outcomes in women with pre-existing lupus nephritis (LN) are variable. The impact of different classes of LN on maternal and fetal outcomes during pregnancy is not well defined, as data is very scarce, especially from the developing countries.

Methods: A retrospective analysis was conducted on 52 women with 89 pregnancies. All had biopsy-proven LN. Those women who conceived at least 6 months after the diagnosis were included. The analysis was conducted between July 1998 and June 2018 at Sindh Institute of Urology and Transplantation (SIUT), evaluating the outcomes for both the mother and the fetus with a minimum follow-up of 12 months after child birth.

Results: The mean maternal age at SLE diagnosis was 21.45 ± 6 years and at first pregnancy was 26.49 ± 5.63 years. The mean disease duration was 14.02 ± 19.8 months. At conception, 47 (52.8%) women were hypertensive, 9 (10%) had active disease while 38 (42.7%) and 42 (47.2%) were in complete and partial remission, respectively. A total of 17 (19.1%) were on mycophenolate mofetil (MMF), which was switched to azathioprine (AZA). Out of 89 pregnancies, 56 (62.9%) were successful, while 33 (37.07%) had fetal complications like spontaneous abortion, stillbirth, perinatal death, and intrauterine growth retardation (IUGR). There were more vaginal deliveries (33 [58.92%]) than caesarean sections (23 [41.07%]). Renal flare was observed in 33 (37.1%) women while 15 (16.9%) developed pre-eclampsia. Proliferative LN was found in 56 (62.9%) cases, but no significant differences were found in maternal and fetal outcomes in relation to LN classes (p = .58). However, disease outcomes at 12 months were significantly poor in those with active disease at the time of conception (p < .05). There was only one maternal death. A total of 10 (11.2%) women showed deterioration in renal function and 5 (5.6%) were dialysis-dependent at 12 months.

Conclusion: The maternal and fetal outcomes in pre-existing LN depend on the disease activity at the time of conception. No correlation was found between International Society of Nephrology/Renal Pathology Society (ISN/RPS) classes of LN and adverse disease and pregnancy outcomes.

Keywords: Pregnancy; fetal loss; lupus nephritis; pre-eclampsia; systemic lupus erythematosus.