Role of foetal umbilical artery Doppler on prediction of adverse pregnancy outcomes in patients with systemic lupus erythematosus.

OBJECTIVES

To investigate the foetal outcomes and examine the predictive value of the third-trimester umbilical artery Doppler in systemic lupus erythematosus (SLE) pregnancies.

METHODS

Data of 180 pregnancies in 175 SLE patients from Jan 2007 to Jan 2017 were analysed retrospectively. Pulsatility index (PI), resistance index (RI), and systolic/diastolic ratio (S/D) of the umbilical artery flow velocity data were monitored by Doppler ultrasound.

RESULTS

One or more composite adverse pregnancy outcomes (APOs) occurred in 46.7% of patients with SLE. A total of 62 (34.4%) pregnancies were pre-term birth, and 34 (18.9%) newborns were small for gestational age (SGA). Twenty-two of pregnancies (12.2%) resulted in foetal distress. In multivariate analysis, predictors of composite APOs included positive anti-Ro (OR 5.5, 95% CI 1.7-18.2, p=0.005) and low complement (OR 3.9, 95% CI 1.1-13.6, p=0.04). Doppler PI, RI, and S/D were significantly higher in the pre-term birth, SGA, and composite APO groups than in the patients without APOs. RI with cut-off values of 0.57 and 0.70 indicated the highest risk of pre-term birth and composite APOs, with sensitivities of 50.0% and 21.4%, as well as specificities of 59.6% and 97.7%, respectively. PI emerged as the best predictor of SGA. The optimal cutoff value for PI was 0.77, at which sensitivity (90.9%) and specificity (49.2%) had the best combination.

CONCLUSIONS

Pregnancies in lupus still had an increased risk of APOs in terms of pre-term birth. Third-trimester umbilical artery Doppler was useful in predicting pre-term birth, SGA, and composite APOs in lupus pregnancies.