in the First Obstetrical Clinic of Vienna from nearly 20% to 2% through the use of handwashing with calcium hypochlorite. Signs and symptoms Signs and symptoms usually include a fever greater than , chills, low abdominal pain, and possibly bad-smelling vaginal discharge. It usually occurs after the first 24 hours and within the first ten days following delivery. Causes After childbirth, a woman's genital tract has a large bare surface, which is prone to infection. Infection may be limited to the cavity and wall of her uterus, or it may spread beyond to cause septicaemia (blood poisoning) or other illnesses, especially when her resistance has been lowered by long labour or severe bleeding. Puerperal infection is most common on the raw surface of the interior of the uterus after separation of the placenta (afterbirth), but pathogenic organisms may also affect lacerations of any part of the genital tract. By whatever portal, they can invade the bloodstream and lymph system to cause sepsis, cellulitis (inflammation of connective tissue), and pelvic or generalized peritonitis (inflammation of the abdominal lining). The severity of the illness depends on the virulence of the infecting organism, the resistance of the invaded tissues, and the general health of the woman. Organisms commonly producing this infection are Streptococcus pyogenes; staphylococci (inhabitants of the skin and of pimples, carbuncles, and many other pustular eruptions); the anaerobic streptococci, which flourish in devitalized tissues such as may be present after long and injurious labour and unskilled instrumental delivery; Escherichia coli and Clostridium perfringens (inhabitants of the lower bowel); and Clostridium tetani. Risk factors Causes (listed in order of decreasing frequency) include endometritis, urinary tract infection, pneumonia/atelectasis, wound infection, and septic pelvic thrombophlebitis. Septic risk factors for each condition are listed in order of the postpartum day (PPD) on which the condition generally occurs. PPD 0: atelectasis risk factors include general anesthesia, cigarette smoking, and obstructive lung disease. PPD 1–2: urinary tract infections risk factors include multiple catheterization during labor, multiple vaginal examinations during labor, and untreated bacteriuria. PPD 2–3: endometritis ( the most common cause ) risk factors include emergency cesarean section, prolonged membrane rupture, prolonged labor, and multiple vaginal examinations during labor. PPD 4–5: wound infection risk factors include emergency cesarean section, prolonged membrane rupture, prolonged labor, and multiple vaginal examinations during labor. PPD 5–6: septic pelvic thrombophlebitis risk factors include emergency cesarean section, prolonged membrane rupture, prolonged labor, and