Single women having IVF will be able to name anyone they like as their baby's father on the birth certificate.
New regulations mean that a mother could nominate another woman to be her child's 'father'.
The 'father' does not need to be genetically related to the baby, nor be in any sort of romantic relationship with the mother.
This mean that "father" is strictly a legal term, not a name for a biological reality that exists independently of the state and its laws.
This raises the spectre of a legal minefield in which female 'fathers' will fight for visitation rights and be chased for child support payments if their fragile relationship with the mother breaks down.
The changes, due to come in on April 6, will apply to many of the 2,000 women a year who have IVF using sperm from anonymous donors.
The regulations are part of the controversial Embryology Bill passed by Parliament last year. The Human Fertilisation and Embryology Authority said they will give lesbian couples in civil partnerships who undergo IVF the same rights as married heterosexual couples.
An unmarried man whose girlfriend has fertility treatment will also find it easier to claim full parental rights.
The new rules state: 'The women receiving treatment with donor sperm (or embryos created with donor sperm) can consent to any man or woman being the father or second parent.' The only exemption is close blood relatives.
Critics said the change would lead to the role of father being downgraded to the one of godfather and warned that the child would be the one to lose out.
I discuss this issue in Session 3, "Same Sex Marriage and the End of Gender" of my 4 part series, Same Sex Marriage Affects Everyone.
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