Puerperal fever (from the latin puer, child), also called childbed fever, can develop into puerperal sepsis, which is a serious form of septicaemia contracted by a woman during or shortly after childbirth or abortion.

The most common infection causing Puerperal Fever is genital tract sepsis. Historically its spread was usually attributable to unsanitary conditions, but in modern medicine can still be caused by the naturally occurring Group A Streptococcus (GAS, Streptococcus pyogenes) bacterium and Group B Streptococcus (GBS, Streptococcus agalactiae, which usually causes less severe maternal disease) .

Other types of infection that can lead to sepsis in the puerperum include urinary tract infection, mastitis and respiratory tract infection (more common after anaesthesia).

Other causal organisms, in order of prevalence, include staphylococci, coliforms, anaerobes, chlamydia, mycoplasma and very rarely, Clostridium welchii.

Puerperal fever is now rare in the West due to improved hygiene during delivery, and deaths have been reduced by antibiotics.