Vaginal Atrophy or Infection: This is a common issue postpartum due to hormonal changes and potential trauma during delivery. Infections or atrophy can lead to unpleasant odors.

Endometritis: An infection of the uterus that can occur postpartum, especially if there were complications during delivery. It can cause a foul odor among other symptoms like fever and abdominal pain.
Perineal Infection or Abscess: If the perineum was torn or cut during delivery, there's a risk of infection, which could cause a bad smell.
Urinary Tract Infection (UTI): Postpartum women are at a higher risk for UTIs, which can cause a strong, unpleasant odor in the urine.

Toxic Shock Syndrome: Although rare, this is a life-threatening condition that can arise from infections. It's characterized by fever, rash, skin peeling, and low blood pressure, and can be associated with the use of tampons or other absorbent products.
Necrotizing Fasciitis: A severe infection that destroys tissue under the skin, including fat and the tissue covering the muscles (fascia). It's rare but can be deadly if not treated promptly.
Septic Pelvic Thrombophlebitis: A condition where a blood clot in the pelvic area becomes infected, leading to sepsis. It's a rare but serious condition that requires immediate medical attention.

Genital or Perineal Cancer: Although extremely rare to present as a new diagnosis with odor as the primary symptom postpartum, any persistent or unusual symptoms should be thoroughly investigated.
Foreign Body: The presence of a foreign body in the vagina or uterus, which could be a retained product of conception or a forgotten tampon, can cause infection and odor.
Fistula: An abnormal connection between the vagina and the rectum or bladder, which can cause continuous leakage of stool or urine, leading to odor. This is more common in areas with limited access to quality obstetric care.