Background It has been reported that rheumatoid arthritis (RA) onset in females is often associated with post-partum period and lactation. Moreover, flares of pre-existing RA occur in 33–91% of cases during post-partum and breastfeeding periods.
Objectives To assess the effect of lactation on RA activity during the post-partum period.
Methods Prospective study included 32 RA pts (ARA criteria, 1987) who were followed up and assessed at 30–34 weeks of pregnancy, and at 1, 3, 6 and 12 months post-partum. Pts' median age was 29 (20–37) years, disease duration 8 (1–28) years. RF (62,1%) and ACPA (58,6%) seropositive, of radiographic stage 2–3 (72,4%) and functional class 1–2 (86,2%) prevailed. At each control visit DAS28CRP score and the number of between the visits flares were obtained among breastfeeding and non-breastfeeding women. RA flare was documented based on changes in DAS28CRP score values vs the previous visit following EULAR recommendations.
Results 6 pts were lost for follow up (FUP; the 1 after Mo 3?, 5 after Mo 5–6 post-partum). Lactation immediately after birth was suppressed in 5 (15,6%)pts. 27 (84,4%)pts were breast-feeding their babies for the period from 2 weeks to 16 months (Me=2,5 [1;6] months). All relevant data on the study population during the FUP is summarized in the Table1.
During the whole FUP the DAS28CRP score was higher among breast-feeding females, although the difference was statistically significant only during the first month post-partum (p=0,01). During the first month post-partum, as well as at Mo3 post-partum RA flares were registered only in nursing mothers, i.e. in 12 out of 27, and in 3 out of 19, respectively. The number of nursing mothers after 3d month was reduced to 8. RA flares in these breast-feeding women were more frequent, than in non-breast-feeders during 3 to 6 months period of the FUP: 6 vs 1 (RR=10,3, 95% CI=2,6;40,1; p=0,0002).Only after 6 mo postpartum the rate of RA flares among nursing mothers did not statistically significant exceed the rate among non-feeders (in 2 out of 5 vs 5 out of 21, p>0,05) (Fig.1).
Assessment of RA flares at all 121 points during 12 months post-partum FUP (59 points during lactation, 62 – after termination of lactation) demonstrate that RA flares were documented in 23 (39%) lactating women and in 6 (9,7%) non-lactating women. Therefore, the risk of RA flare in lactating women was 4-fold higher vs the risk in non-lactating women (RR=4; 95% CI=1,8;9,2; p=0,0002).
Increased RA exacerbation rates among nursing mothers is partially explained by postponement of active therapy. The majority of pts refused initiation of therapy for the sake of breastfeeding.
Approaches to breastfeeding practices in RA mothers should be individual. Nursing is acceptable during RA remission or low disease activity given the patient continues on the recommended drugs, compatible with breast-feeding.
Conclusions Lactation and breastfeeding is associated with 4-fold higher risk of RA exacerbation as compared to non-breastfeeding population (RR=4; 95% CI=1,8;9,2; p=0,0002)
Hazes JM at all. Rheumatoid arthritis and pregnancy: evolution of disease activity and pathophysiological considerations for drug use. Rheumatology. 2011 Nov;50(11):1955–68.
Disclosure of Interest None declared