You're most likely to be fertile if your ejaculate — the semen discharged in a single ejaculation — contains at least 15 million sperm per milliliter. Too little sperm in an ejaculation might make it more difficult to get pregnant because there are fewer candidates available to fertilize the egg.
The study of skin, the science of dermatology, has undergone significant transformations throughout the centuries. From the first descriptions of skin diseases in Egyptian papyri and in Hippocratic writings to the first treatises on dermatology, important individuals and discoveries have marked the specialty. In the 18th and 19th centuries, the specialty consolidated itself as a field of medical study based on the first classifications of dermatoses, diagnostic methods, and drug treatments. In the 20th century, the scientific and technological revolution transformed dermatological practice, incorporating new therapeutic resources, as well as surgical and aesthetic procedures.
