Background Prior studies have suggested higher rates of preterm birth in pregnancies to women with rheumatoid arthritis.
Objectives We sought to identify differences in the pregnancy outcomes of women with and without RA, and pregnancies that occurred prior to and following RA diagnosis.
Methods A cross-sectional survey was completed by 75 women with RA age-matched to 75 women without RA. Information collected about each prior pregnancy included: pregnancy outcome (spontaneous abortion, stillbirth, elective termination, ectopic pregnancy, or live birth); the timing of delivery; infant anomalies; methotrexate exposure in pregnancy; and whether the pregnancy was planned. Simple statistics were used to compare pregnancy outcomes between women with and without RA and pregnancies prior to and following RA diagnosis.
Results The majority of women with RA (83%) and controls (64%) were white, and 11% of women with RA and 28% of controls were African American. About half of controls and 31% of women with RA had education beyond college. The average age at the time of the survey was 32 years (SD: 5) in both RA patients and controls, and the average age at RA diagnosis was 23 years (SD: 10). There were 76 pregnancies in 40 women with RA and 99 pregnancies in 33 healthy controls (see table). The overall rates of live birth, spontaneous abortion, and ectopic pregnancies were similar between groups; there were no stillbirths.
The rate of elective termination was significantly different, with 9% of RA and 30% of control pregnancies terminated (p=0.005). The large majority of the terminations in women with RA occurred prior to diagnosis. The higher frequency of unplanned pregnancy among the controls (38% unplanned RA vs 67% unplanned controls, p=0.0002) likely contributed to this higher termination rate. Of unplanned pregnancies, 45% were terminated in controls, 33% in pre-RA pregnancies, and 9% in post-RA pregnancies. No planned pregnancies were terminated. Three pregnancies in women with RA were exposed to methotrexate (2 unplanned, 1 planned) resulting in 2 spontaneous abortions and 1 live birth, born at term without any reported abnormalities.
The rates of preterm birth and infant abnormalities did not differ significantly between those with and without RA, though among women with RA, all preterm births and infant abnormalities occurred after RA diagnosis. Each of the RA preterm births was delivered between 31–34 weeks gestation. Preeclampsia was more common in women with RA, but did not differ significantly between pregnancies prior to and after RA diagnosis.
A total of 41% of the post-RA pregnancies had an adverse pregnancy outcome (miscarriage, preterm delivery, or infant abnormality), compared to 13% of pre-RA pregnancies (p=0.01) and 20% of control pregnancies (p=0.01).
Conclusions Women with RA, overall, had similar rates of miscarriage, stillbirth, and ectopic pregnancy compared to healthy women, but pregnancies that occurred after RA diagnosis had higher rates of these adverse outcomes. More pregnancies in women with RA were planned, leading to a lower rate of elective termination.
Acknowledgements This study was funded by Pfizer.
Disclosure of Interest M. Clowse Grant/research support from: Pfizer, Janssen, Consultant for: UCB, G. McDaniel: None declared, A. Eudy: None declared