Lesbian and gay couples have been creating families for some time now.

Lesbian couples will use known or anonymous sperm donors and gay couples will go through surrogacy arrangements.

As part of the wider movement towards eliminating discrimination towards same sex individuals / couples, the law is playing catch up.   We have seen success recently with the first reading of the Equal / Same sex marriage Bill at the House of Commons and now judgements are being delivered to acknowledge and protect parents and children in alternative family structures.

Until then, I continue to advise lesbian and gay couples to seek legal advice before they start the process of creating a family.  The legal relationships that you intend on creating are not always possible unless you do things in a certain way compliant with existing albeit outdated, law. 
It is devastating to discover that you are not the legal parent once the child is born.   For the sperm donor, finding yourself as a legal father when the opposite was intended, leads to obligations both financial and parental. 

Get legal advice before you start the process.  The last thing you want to do when the child is born is start litigation. 

Best regards

Harjit Sarang