Maternal Risk Factors for Lactation Mastitis: A Meta-analysis

This meta-analysis was conducted to identify maternal risk factors for lactational mastitis. Studies published in English or Chinese were retrieved from Medline (PubMed), Embase, Cochrane Library, Web of Science, CNKI, WANFANG, and VIP databases according to predefined inclusion and exclusion criteria. Study quality was assessed by the Newcastle-Ottawa Scale. A random-effects model was used for data pooling and I-2 tests to assess study heterogeneity. Pooled data from 8 cohorts and 10 case-control studies identified previous mastitis during breastfeeding (P<0.00001), cesarean section (P=0.001), breast trauma (P<0.001), anemia (P=0.0001), latch problems <= 8 weeks post-delivery (P=0.003), milk overproduction (P=0.002), blocked duct (P<0.0001), cracked nipple (especially <= 4 weeks post-delivery) (P=0.0001), use of nipple shields (P<0.00001), nipple cream (P<0.0001), brassieres (P<0.0001), and breast pumps (P<0.00001), and breastfeed duration > 30 min (P=0.008) as significant risk factors. Washing nipples before breastfeeding decreased lactational mastitis risk. Identification of these risk factors may facilitate the development of nursing care protocols for reducing lactational mastitis.