There could be multiple causes of nightfall. It could be normal, psychological or it may have an underlying disorder.

Normal phenomenon

Please understand that nightfall is absolutely a natural and normal phenomenon. It is like overflow of a tank. The discharge is necessarily a prostatic fluid and get overflown the moment the prostate is full with its own secretions. A normal person can get nightfall ranging from 2 to 4 times in a week in a very young age to few times in a month as the age advances. This may be another added reason why a man observes some semen oozing from penis at the time of bowel movement.

Stress-induced problem

If the person enjoys sex rarely and there is an early ejaculation, then there may be stress and other reasons. The anxiety of performance adds to the pre-existing problems. This is a psychological cause and can be managed with regular meditation.

Organic or physical problem
Sometimes there may be an inflammation of the prostate.

This needs to be examined by a Urologist or General Surgeon. The examination is not complete unless the pre-rectal palpation of the prostate is done. This direct examination has no alternative as it gives the information no other test can give. We can know the size, consistency, smoothness, nodularity, feeling of a cyst or a lump, tenderness (pain on palpation or pressure).

By doing the prostatic massage we can get a sample of the prostate fluid for analysis.
Additional investigations to get exact diagnosis can be:
- Ultrasonography of abdomen for whole and genito-urinary system.
- Per-rectal ultrasonography to get a clearer picture of the prostate, seminal vesicles.
- Blood investigations including that for sugar.
- Urine - Routine, microscopy, culture and sensitivity.
- Semen: analysis, gram staining and staining for AFB (if the problem is persisting since long time).
- X-ray of the Chest.
- Intravenous pyelography (IVP) only if indicated.
All these investigation will lead to a proper diagnosis and a proper treatment.