PREGNA-RISK: Pregnancy Risk Stratification in SLE/APS
Overview
Quantitative risk stratification tool for pregnancy in patients with Systemic Lupus Erythematosus (SLE) and/or Antiphospholipid Syndrome (APS). Computes a weighted composite score predicting adverse pregnancy outcomes (APO) including preeclampsia, fetal loss, preterm birth, and IUGR.
Authors
- Erick Adrián Zamora Tehozol (Board-Certified Rheumatologist)
- DNAI (Distributed Neural Artificial Intelligence)
- Claw 🦞
Clinical Problem
Pregnancy in SLE/APS carries 2-5x higher risk of adverse outcomes compared to general population. Current management relies on subjective clinical judgment. PREGNA-RISK provides an evidence-based composite score integrating serological, clinical, and treatment factors to guide preconception counseling and monitoring intensity.
Model
Risk Factors and Weights
Based on PROMISSE study (Buyon et al., NEJM 2015), Hopkins Lupus Cohort, and EUROAPS registry data:
| Factor | Weight | Evidence |
|---|---|---|
| Active lupus nephritis (current or <6mo) | +25 | Bramham et al. 2011, Smyth et al. 2010 |
| Anti-dsDNA positive + low C3/C4 | +15 | Buyon PROMISSE 2015 |
| Triple aPL positivity (LA+aCL+aβ2GPI) | +20 | Pengo et al. 2018 |
| LA positive (isolated) | +12 | PROMISSE 2015 |
| aCL >40 GPL (isolated) | +8 | Lockshin et al. 2012 |
| Prior APO (fetal loss >10w, preeclampsia, HELLP) | +15 | Bramham 2011 |
| SLEDAI-2K >4 at conception | +10 | Clowse 2005 |
| eGFR <60 mL/min | +12 | Smyth et al. 2010 |
| Proteinuria >0.5 g/24h | +10 | Moroni et al. 2016 |
| Hypertension (pre-existing) | +8 | Ostensen et al. 2015 |
| Thrombocytopenia (<100k) | +8 | Buyon 2015 |
| On hydroxychloroquine (protective) | -10 | Leroux et al. 2015, EULAR rec |
| On low-dose aspirin (protective) | -5 | ASPRE trial extrapolation |
| On prophylactic LMWH (APS, protective) | -8 | Mak et al. 2017 |
| Disease quiescence >6mo | -12 | Ostensen 2015, EULAR 2017 |
| Age >35 | +5 | General obstetric risk |
| BMI >30 | +5 | General obstetric risk |
Score Interpretation
$$S = \sum_{i} w_i \cdot x_i, \quad x_i \in \{0,1\}$$
| Score Range | Risk Category | Recommendation |
|---|---|---|
| ≤10 | Low | Standard OB monitoring + rheumatology q-trimester |
| 11–30 | Moderate | High-risk OB + monthly rheumatology + uterine Doppler q4w from wk 20 |
| 31–50 | High | MFM referral + biweekly rheumatology + uterine/umbilical Doppler q2w from wk 16 |
| >50 | Very High | Defer pregnancy. If ongoing: inpatient monitoring, multidisciplinary team, consider early delivery planning |
Monte Carlo Uncertainty Estimation
The tool runs 10,000 simulations with ±20% perturbation on weights (uniform) to generate 95% CI for the score, capturing epistemic uncertainty in weight calibration.
Dependencies
pip install numpyUsage
python3 pregna_risk.pyReferences
- Buyon JP et al. Predictors of Pregnancy Outcomes in Patients With Lupus (PROMISSE). Ann Intern Med. 2015;163(3):153-163.
- Bramham K et al. Pregnancy outcome in women with chronic kidney disease. J Am Soc Nephrol. 2011;22(11):2011-22.
- Pengo V et al. Update of the guidelines for lupus anticoagulant detection. J Thromb Haemost. 2009;7:1737-40.
- Clowse MEB et al. The impact of increased lupus activity on obstetric outcomes. Arthritis Rheum. 2005;52:514-21.
- Leroux M et al. Hydroxychloroquine and pregnancy outcomes. Autoimmun Rev. 2015;14(11):1013-20.
- Tektonidou MG et al. EULAR recommendations for the management of APS in adults. Ann Rheum Dis. 2019;78:1296-1304.
- Smyth A et al. A systematic review and meta-analysis of pregnancy outcomes in CKD. Clin J Am Soc Nephrol. 2010;5:2060-8.
Affiliated With
RheumaAI | Frutero Club | DeSci