Epidemiology of Mastitis

Editor(s): G. Ryan and C. Purandare.

Epidemiology of Mastitis 

Gillian A. Ryan and Chittaranjan N. Purandare

Key Messages 
  • Mastitis is one of the most common problems encountered by the breast­feeding mother
  • Many women stop breastfeeding due to mastitis or breast abscesses
  • Prevention of mastitis is very import­ant in supporting of breastfeeding 
Breastfeeding and lactation are an in­tegral part of reproductive physiology. Breastfeeding is recommended as the exclusive source of nutrition for infants in the first 6 months of life by many international bodies, including the American College of Obstetricians and Gynecologists, WHO, and FIGO. Fur­thermore, continued breastfeeding is recommended along with appropriate complementary foods up to two years of age or beyond [1, 2]. However, many women stop breastfeeding due to mastitis or breast abscesses. As ob­stetricians, it is important that we not only support breastfeeding mothers to achieve successful breastfeeding but also that we should be aware of the common complications that can occur as a result of breastfeeding and the most appropriate management of these conditions. This is important for the health and well-being of both the mother and the child, but also as women who experience breastfeeding difficulties are at higher risk of post­partum depression, and should be screened, treated, and referred appro­priately [1]. 

Mastitis is one of the most common problems encountered by the breast­feeding mother. It is an inflammatory condition of the breast and may occur with or without infection. It is also commonly termed lactational mastitis or puerperal mastitis. Lactational mas-titis has been estimated to occur in ap­proximately 2–10% of all breastfeeding women [3, 4], though the reported in­cidence varies from one population to another, with some studies quoting rates as high as 30% [4]. The most common time of occurrence of masti-tis is in the second or third week post­partum [4]. The development of a breast abscess is a severe complica­tion of mastitis. This is a localized col­lection of pus within the breast, and the incidence is approximately 0.1–3% [5, 6]. The occurrence of a breast ab­scess is also commonest in the first 6 weeks postpartum, but may also occur later [4], and it can occur with or with­out preceding mastitis. 

lactation mastitis

The incidence of mastitis requiring hospitalization is low; one study by Staf­ford et al. [7] included 136,459 new mothers, and found 127 women re­quired hospitalization for mastitis, which resulted in an incidence of 9 per 10,000 deliveries. Although generally easily treatable with antibiotics, it can occa­sionally be fatal if inadequately treated. Research suggests that mastitis also increases the risk of transmission of HIV to the infant through breastfeed­ing [8]. Although complications can oc­cur, it is typically easily treated with an­tibiotics; and with the appropriate support and education, breastfeeding can be continued. 

  1. American College of Obstetricians and Gyne­cologists’ Committee on Obstetric Practice; Breastfeeding Expert Work Group: Committee Opinion No. 658 Summary: optimizing support for breastfeeding as part of obstetric practice. Obstet Gynecol 2016;127:420–421.
  2. WHO: Breastfeeding. http://www.who.int/ topics/breastfeeding/en/
  3. Committee on Health Care for Underserved Women, American College of Obstetricians and Gynecologists: ACOG Committee Opinion No. 361: breastfeeding: maternal and infant aspects. Obstet Gynecol 2007;109:479–480.
  4. Department of Child and Adolescent Health and Development, World Health Organization: Mastitis – Causes and Management. Geneva, World Health Organization, 2000.
  5. Dener C, Inan A: Breast abscesses in lactating women. World J Surg 2003;27:130.
  6. Amir LH, Forster D, McLachlan H, Lumley J: Incidence of breast abscess in lactating women: report from an Australian cohort. BJOG 2004;111:1378.
  7. Stafford I, Hernandez J, Laibl V, Sheffield J, Roberts S, Wendel G Jr: Community-acquired methicillin-resistant Staphylococcus aureus among patients with puerperal mastitis requiring hospitalization. Obstet Gynecol 2008;112:533–537.
  8. Semrau K, Kuhn L, Brooks DR, Cabral H, SinkalaM, Kankasa C, Thea DM, Aldrovandi GM: Dynamics of breast milk HIV-1 RNA with unilateral mastitis or abscess. J Acquir Immune Defic Syndr 2013;62:348–355.