There is an echo of surrogacy in the Old Testament ie where a wife is childless another woman bears children for the husband: Abraham (Hagar), Jacob (Bilah, Zilpah) (see https://www.conformingtojesus.com/charts-maps/en/genealogy_of_abraham.h…). There are however large cultural differences and the other mothers are effectively part of a large family, but there is still a sense that it's not the best way as Abraham discovered with Ishmael and Issac.
“What are the consequences to the God-designed union between husband and wife? God created marriage, sex, conception, and childbirth to function as interwoven events of a single natural continuum. focusonthefamily.com
But by artificially separating those acts, modern science oversteps its boundaries — and the sanctity of marriage is at risk. Is it possible that couples who use surrogacy are essentially guilty of adultery or a breach of the marriage covenant?
Do we fully understand the implications of turning conception and childbearing into services for hire? Even the idea of “renting a womb” is ethically questionable.
What about the child? Who does she belong to, really? (We’re not talking about legality, here — but spiritually, morally, and emotionally.) Does surrogacy make the child a commodity?
Is the potential surrogate mother carefully considering her own well-being? The contract might have been met. But maternal instinct could make it painfully difficult to part with the child she’s carried in her body for nine months.” Perspectives on surrogate motherhood
The focus has always to be on the children and here the evidence indicates that they are more likely to experience emotional turmoil - some of the research: Emotional Problems... (British Journal of Education, Society and Behavioural Science) My daddy's name is Donor (pdf)
Some have been more forthright:
Republic of Irish Senator Sharon Keogan “wholeheartedly objects to the commercialisation of the human child and the relegation of women to the status of simply incubator or wombs for hire...Surrogacy I believe is harmful, it is exploitative and it is unethical. I don’t believe it is everyone’s right to have a child.” quoted
From: https://www.gov.uk/legal-rights-when-using-surrogates-and-donors
Surrogacy is legal in the UK, but if you make a surrogacy agreement it cannot be enforced by the law.
If you use a surrogate, they will be the child’s legal parent at birth.
If the surrogate is married or in a civil partnership, their spouse or civil partner will be the child’s second parent at birth, unless they did not give their permission.
Legal parenthood can be transferred by parental order or adoption after the child is born.
If there is disagreement about who the child’s legal parents should be, the courts will make a decision based on the best interests of the child.