(DI) Assisted insemination in which semen from a sperm donor (who is not the husband) is used.

Achieving pregnancy with the help of a third party to provide any of: the spermatozoa (see donor insemination); the oocytes (egg donation); or the uterus (surrogacy: see gestational surrogacy and traditional surrogacy). Current issues surround the question of whether or not to inform the child of his or her origins, whether the donor or surrogate should be anonymous or take some part in the child's upbringing, exploitation and autonomy, and (in the case of sperm donation) access to sperm banks by women not in a heterosexual relationship with a sterile man.

A form of collaborative reproduction comparable in some ways to sperm donation (see donor insemination), but different in that eggs for donation are much harder to obtain physically than ejaculated sperm are; generally the egg donor undergoes all the steps needed for in vitro fertilisation up to the stage of egg retrieval.

(IUI) A form of assisted conception involving assisted insemination into the uterus, either for donor insemination (DI) or with husband's semen (AIH). IUI can be carried out with a woman's natural cycles or with ovarian stimulation (superovulation) using clomiphene or follicle stimulating hormone, with ovarian monitoring.