Ejaculation During puberty 

The first ejaculation in males often occurs about 12 months after the onset of puberty, generally through masturbation or nocturnal emission . This first semen volume is small. The typical ejaculation over the following 3 months produces less than 1 milliliters of semen. The semen produced during early puberty is also typically clear. After ejaculation this early semen remains jellylike and, unlike semen from mature males, fails to liquify. A summary of semen development is shown in Table 1.

Most first ejaculations lack sperm. Of the few early ejaculations that do contain sperm, the majority of sperm lack motion. The remaining sperm have abnormal motion.

As the male proceeds through puberty, the semen develops mature characteristics with increasing quantities of normal sperm. Semen produced 12 to 14 months after the first ejaculation liquifies after a short period of time. Within 24 months of the first ejaculation, the semen volume & the quantity & characteristics of the sperm match that of adult male semen.
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