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Pre-pregnancy serum complement C3 level is a predictor of preterm birth for pregnancies with systemic lupus
Yuri Hiramatsu1, Kentaro Isoda1,2, Takuya Kotani3
1Department of Internal Medicine (IV), Osaka Medical College, Daigaku-Machi 2-7, Takatsuki, Osaka, 569-8686, Japan.
Insights
Preterm birth in systemic lupus erythematosus (SLE) is predicted by a history of lupus nephritis and low pre-pregnancy serum complement 3 (C3) levels. Monitoring these factors is crucial for preconception care in SLE patients.
Area of Science:
- Obstetrics and Gynecology
- Rheumatology
- Immunology
Background:
- Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect pregnancy outcomes.
- Preterm birth is a significant concern in pregnancies complicated by SLE.
- Understanding predictors of preterm birth is essential for improving preconception care and maternal-fetal health.
Purpose of the Study:
- To identify pre-pregnancy predictors of preterm birth in women with SLE.
- To evaluate the role of preconception care in mitigating preterm birth risk.
- To analyze clinical characteristics and disease activity associated with preterm birth in SLE pregnancies.
Main Methods:
- Retrospective analysis of 108 pregnancies in 74 SLE patients.
- Comparison of pre-pregnancy clinical characteristics and disease activity between preterm and full-term birth groups.
- Multivariate analysis to identify significant risk factors for preterm birth.
Main Results:
- 25% of SLE pregnancies resulted in preterm birth.
- Lower pre-pregnancy serum complement 3 (C3) levels were observed in the preterm birth group.
- History of lupus nephritis and low pre-pregnancy C3 (< 85 mg/dl) were identified as significant risk factors for preterm birth.
- Increased number of risk factors correlated with a higher preterm birth rate.
Conclusions:
- History of lupus nephritis and low pre-pregnancy C3 levels are key predictors of preterm birth in SLE.
- Preconception management focusing on serum complement levels is vital for SLE patients, especially those with a history of lupus nephritis.
- Targeted preconception care can potentially reduce the incidence of preterm birth in this high-risk population.
Background:
This study aimed to clarify predictors of preterm birth in pregnancy of women with systemic lupus erythematosus (SLE). We investigated the predictors of preterm birth before pregnancy from the perspective of the importance of preconception care.
Methods:
We analysed fetal outcomes of 108 pregnancies in 74 SLE patients in a retrospective study. We compared pre-pregnancy clinical characteristics and disease activity in these women between the preterm birth and full-term birth groups to select predictive factors for preterm birth before pregnancy.
Results:
Eighty-three of 108 pregnancies resulted in live births, of which 27 (25.0%) were preterm births. Pre-pregnancy serum complement 3 (C3) level was significantly lower in the preterm birth group (77.0 mg/dl) than the full-term birth group (87.5 mg/dl) (P = 0.029). Multivariate analysis identified history of lupus nephritis (odds ratio: 5.734, 95% CI 1.568-21.010, P = 0.008) and low C3 level (< 85 mg/dl) at pre-pregnancy (odds ratio 4.498, 95% CI 1.296-15.616, P = 0.018) as risk factors for preterm birth. The greater the number of these risk factors, the higher was the preterm birth rate (P = 0.0007). In the case of SLEDAI score ≤ 4, the preterm birth rate was higher in the pre-pregnancy low C3 group (< 85 mg/dl) (42.1%) than in the high C3 group (C3 ≥ 85 mg/dl) (14.7%) (P = 0.018).
Conclusion:
For patients with a history of LN, treatment management focusing on pre-pregnancy serum complement levels is very important.
