Is surrogacy allowed in christianity?

Honest question, pls no negativity.

Sex outside marriage isn't allowed so what about surrogacy? It's not her egg nor her husbands sperm, and she didnt actually do the deed but it's still someone elses sperm growing inside her.

I often see women getting praised for her surrogacy pregnancy, but is it in fact a good deed she's doing or is she sinning?