Mastitis is a breast infection that affects as much as a third of breastfeeding women, up to 11% of whom develop a complication of lactational breast abscess. Non-lactational mastitis and breast abscesses are infrequent. Ultrasound-guided needle aspiration is the recommended method of treatment for breast abscesses with incision and drainage reserved for complicated, large or necrotising abscesses.

Despite guideline recommendations, there is evidence to suggest significant variation in practice, particularly concerning antibiotic prescribing, rates of incision and drainage and length of inpatient treatment. At least 40% of women are prescribed inappropriate antibiotics and one in three women are admitted for inpatient treatment. However, the rate of incision and drainage is of particular interest as the incidence differs dramatically between studies from 1% to over 85%.

Inappropriate antibiotic prescribing not only delays treatment but can result in significant infection and hospital admission. Unnecessary operative intervention carries increased risk of cosmetic disfigurement and has significantly higher cost, compared to outpatient ultrasound-guided aspiration. Unnecessary hospital admission is not only wasteful of limited NHS resources but is very disruptive to mother and baby.

Considering that the majority breast surgeons are no longer participating in the on-call rota and the acute presentation of primary breast infections, we hypothesise that such variation in practice indeed exists across the UK and Ireland where patients are treated by the non-specialist general surgeons. However, in order to improve current practice, we need to confirm our hypothesis.


The aim of the MAMMA study is to describe the current practice in the management of mastitis and breast abscesses in the UK and Ireland and to provide recommendations for best practice.

The objectives of the MAMMA study are:

  1. Understand patient treatment pathways and patterns of sub-specialty involvement
  2. Identify variation between different centres, specifically in terms of antibiotic prescribing, rate of operative versus radiological management, waiting time to ultrasound scan, rate of inpatient versus outpatient treatment, length of hospital stay, rate of follow-up by breast surgeons, number of outpatient appointments
  3. Generate data to improve current guidelines on the management of mastitis and breast abscess
  4. Determine the feasibility of ongoing prospective international annual re-audit

Inclusion/ exclusion criteria

Inclusion criteria:

  • Female >16 years of age
  • Symptoms of mastitis or breast abscess

Exclusion criteria:

  • Male patients
  • Underlying pathology of breast cancer
  • Breast surgery within 90 days of presentation
  • Breast implant in situ on the affected side


Total number of sites planned

200 sites


Aug 2020 - Dec 2020: Phase 1 -  International Practice Survey

Sept 2020 - Mar 2021: Phase 2 - Prospective Audit (3 months data collection interval)

Dec 2020 – Apr 2021: Phase 2 - Data Validation (based on centre’s entry point)

Contact information and website

MAMMA website