Surrogacy is legal in the UK, but surrogate mothers cannot be paid. They can accept only "reasonable expenses" for costs incurred during the pregnancy.
Kim Cotton, the mother in the famous 1985 case, went on to set up COTS (Childlessness Overcome Through Surrogacy) in 1988, which gives help and advice to surrogates and childless couples in the UK.
She resigned in May 1999 complaining the government was cracking down on surrogacy.
She is now managing director of Tablewhere, a china matching company based in North London. "Today I still help people but I match china rather than surrogates to couples," she told BBC On This Day.