Adverse pregnancy outcomes and risk of subsequent rheumatoid arthritis.

Publication Type:

Journal Article


Arthritis and rheumatism (2013)


2013, Clinical Research Division, January 2014


Objective: Pregnancy and reproductive outcomes have been associated with altered risk of some autoimmune diseases including rheumatoid arthritis (RA). We sought to determine whether prior pregnancy resulting in a low birthweight (LBW) infant or preterm birth (PTB) is associated with risk of subsequent RA in the mother. Methods: We conducted an analysis of RA risk in parous women from a population-based prospective study of newly diagnosed RA cases and age-matched controls. The primary outcome measure was disease status (RA vs. control), with exposures of prior PTB and prior delivery of an infant with LBW (< 2500 grams), very low birthweight (VLBW, < 1500 grams), or extremely low birthweight (ELBW, < 1000 grams). A pre-planned analysis including only rheumatoid factor (RF) positive RA cases was also conducted. Results: 202 RA cases and 1102 control subjects were analyzed. Prior delivery of an infant with ELBW was associated with RA in the mother (RR 3.7, 95%CI 1.0-13.2). Prior VLBW (RR 4.0, 95%CI 1.3-11.4) and ELBW (RR 5.5, 1.4-22.4) were associated with RF-positive RA. Prior LBW and PTB were more common among RA cases than controls, but differences were not statistically significant. Conclusion: Compared to those with uncomplicated pregnancies, women with a prior VLBW or ELBW delivery had a higher risk of RA, particularly RF-positive RA. This association may reflect common risk factors for pregnancy complications and RA. Alternatively, complicated pregnancy itself may confer risk for subsequent RA. © 2013 American College of Rheumatology.