Selection of five plastic petri dishes, three circular, one square and one plastic, sample tube with screw top, 'Nung' and 'Falcon' brand, unsigned, Europe, 1999. Used to incubate embryos in the IVF process (see note).

Eggs are fertilised with sperm in a laboratory and grown in tubes during IVF (in vitro fertilisation). Embryos consist of eight or 12 cells. They remain in the tubes until they are three days old. A small number of embryos are implanted in the womb after these three days.

IVF was pioneered in the UK in 1978. It remains controversial. It is expensive and invasive. Only a low percentage of procedures result in a successful live birth. There is also a higher chance of multiple births causing risk to both mother and foetuses. Opponents of IVF argue unused embryos are used for experimentation. This raises issues of human rights as well as when an embryo becomes a human being.