Written and Medically Reviewed by Dr Benjamin George, MBBch, BAO, LRCP & SI, FRCS, AM, ISAPS, CMTP. Updated as of May 15, 2021.
What is pre-ejaculation (or pre-cum)?
Pre-ejaculation, or more colloquially pre-cum, is a whitish fluid that is discharged from a penis when aroused and can unknowingly occur any time during arousal but more commonly right before ejaculation. The pre-ejaculation fluid comes from the bulbourethral glands (also known as the 'cowpers gland'), which are two pea-sized glands under the prostate gland on either side of the most internal end of a penis. From each of the glands are tiny ducts leading to different sections of the urethra.
What does pre-cum do?
Pre-cum has two core functions:
- Neutralize acidity of urethra tract;
- Provide a natural lubricant for sexual intercourse.
The male sperm cells are sensitive to acidic pH levels, often killing the sperm. Hence, our urine, which also utilizes the urethra tract, is naturally acidic and can often linger after urination. The alkalinity of the pre-ejaculation fluids helps to neutralize any remnants of acidity in the urethra prior to ejaculation so that the sperm can have a pathway out 'alive'. In essence, pre-cum is the sanitation personnel for the sperm cells.
The second purpose of pre-ejaculate is to serve as lubrication for sexual intercourse. There are actually glands that serve a similar purpose in women, called the Bartholin's glands (two pea-sized glands in a woman that creates alkaline mucus to produce natural lubrication for sex).