Hi, thanks for posting the concern in HCM. My understanding is, fever at any point of time suggests some infection or active inflammation. Fever post delivery may be due to infection of the wounds of episiotomy or cesarean section or infection of retained placental products. The latter also presents with refractory bleeding per vagina. Or else, the fever may be due to some unrelated non-obstetric reason. This may be due to some bacterial or viral infection, vascularity etc. ESR also remains high during most infection and ongoing inflammatory activity. If the routine blood tests are negative, a blood culture (aerobic+anaerobic), ANA, viral screening (Hbsag, anti HCV, HIV), LFT, USG whole abdomen, Urine for Routine examination and culture and sensitivity and Stool for routine examination should be done. A coagulation profile may also be performed. Decline in ESR after 5days of antibiotic may be due to reduction of infection. However, it would be better if you can attach all the investigation reports in a premium query. Please also consult your Obstetrician and local physician for further evaluation. Please maintain healthy diet, good oral hydration and use antipyretic medicine only when temperature is more than 100degree F. Empirical antibiotic treatment can be done, but with caution to prevent emergence of resistance. For any further information, please write back to me directly. Regards