What does the medical abbreviation PN mean?

The medical abbreviation PN can mean:

1) Paroxysmal Nocturnal Hemoglobinuria - A rare blood disorder in which red blood cells are destroyed during the night-time.

2) Peripheral Neuropathy - A condition that affects the nerves outside the brain and spinal cord.

3) Pneumonia - An infection that causes inflammation in the lungs.

4) Psychological Nursing - A branch of nursing that focuses on the mental and emotional health of patients.

5) Postnatal - Relating to the period after childbirth.