A 25-year-old woman develops fever (38.9°C), foul-smelling lochia, and uterine tenderness on day 4 postpartum after prolonged labour with ruptured membranes for 18 hours. The most common causative aetiology of puerperal endometritis in this clinical context is:

• A Group A Streptococcus (Streptococcus pyogenes)
• B Staphylococcus aureus
• C Chlamydia trachomatis
• D Polymicrobial infection (anaerobes, Gram-negative aerobes, Group B Streptococcus) ✓

Explanation

Puerperal endometritis is predominantly polymicrobial, involving vaginal flora including anaerobes (Bacteroides, Peptostreptococcus), aerobic Gram-negative bacilli (E. coli, Klebsiella), Group B Streptococcus, and Enterococcus. Group A Streptococcus causes the most severe, rapidly progressing puerperal sepsis but is less common overall. Chlamydia causes late-onset subacute endometritis. The polymicrobial aetiology dictates empirical broad-spectrum antibiotic coverage.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.