Background/Purpose: Systemic lupus erythematosus (SLE) is a complex autoimmune disease most frequently affecting women of childbearing age. Women with SLE are known to be at increased risk of miscarriage and other complications during pregnancy. This study used a large health claims database to quantify the reported incidence of maternal and fetal complications in pregnant women with SLE compared to pregnant women without SLE.  

Methods: A retrospective observational analysis of the MarketScan US administrative healthcare claims database from 2006 to 2012 was conducted. Records of all women aged 12-54 years were reviewed. SLE patients were defined by ICD-9 codes for 710.0 on at least 2 different days. Pregnancies were identified by including codes for live birth, miscarriage, and either first-or second trimester ultrasound. Pregnant women with SLE were matched 1:5 by index year and quarter, age, geography, data type, insurance plan type, and employee relationship with pregnant women without SLE.  Conditional logistic regression was used to calculate p values. Statistical tests were not corrected for multiple comparisons. P values are presented in the table.  

Results: 1721 pregnancies in women with SLE were matched with 8605 pregnancies in women without SLE. Demographics were similar; mean (± SD) age of 31.5 (± 5.6) in the SLE group and 31.4 in (± 5.6) in controls. 23 in every 100 SLE pregnancies resulted in a miscarriage before 22 weeks gestation vs. 19 in every 100 control pregnancies. There was an increased risk of threatened abortion/premature labour without delivery in pregnancies with SLE vs. those without (46.0% vs. 39.8%). Hypertension was reported in 28.4% of SLE pregnancies vs. 12.4% of controls. Preeclampsia occurred in 1 in every 10 SLE pregnancies vs. 1 in every 22 non SLE pregnancies. Preterm delivery occurred in 1 in every 9 SLE pregnancies vs. 1 in every 17  non SLE pregnancies, with stillbirths reported in 2.4% of SLE pregnancies vs. 1.3% of subjects without SLE. There was a 7.5% increase in the risk of fetal complications in pregnancies with SLE vs. those without. A code for known/suspected fetal abnormality affecting management of the mother occurred in 39.7% of SLE pregnancies vs. 28.0% of controls.

Conclusion:

In this large database analysis of over 10,000 pregnant women, those with SLE had a higher risk for suspected fetal abnormalities affecting care of the mother, and a doubling of risk for hypertension, preeclampsia, pre-term delivery and stillbirths. However, increased risk for earlier adverse pregnancy events, including miscarriage prior to 22 weeks and threatened abortion, appeared modest.  These data highlight the need for regular physician-patient interaction, counseling and high quality education for women with SLE who are pregnant or looking to conceive to ensure possible complications are recognized early and managed appropriately.