Progression

Initiation

Pregnancy occurs as the result of the female gamete or oocyte being penetrated by the male gamete spermatozoon in a process referred to, in medicine, as "fertilization", or more commonly known as "conception". After the point of "fertilization" it is referred to as an egg. The fusion of male and female gametes usually occurs through the act of sexual intercourse. However, the advent of artificial insemination and in vitro fertilisation have also made achieving pregnancy possible in cases where sexual intercourse does not result in fertilization (e.g. through choice or male/female infertility).