Unlike most nonmammalian animals, scorpions are viviparous, giving birth to live young instead of laying eggs. Once fertilized, the eggs are retained in the female's body, where the embryos are nourished in utero for periods varying from several months to a year.
Most scorpions reproduce sexually, with male and female individuals; species in some genera, such as Hottentotta and Tityus, and the species Centruroides gracilis, Liocheles australasiae, and Ananteris coineaui have been reported, not necessarily reliably, to reproduce through parthenogenesis, in which unfertilized.
The proteins in plasma include the antibody proteins, coagulation factors, and the proteins albumin and fibrinogen which maintain serum osmotic pressure.