Surrogacy is not "orgasmic" but it is sexual by definition, since we procreate sexually. It's called sexual reproduction. Having offspring is a major part, maybe the major part, of human sexuality, of being a male or a female.
Having children with anybody other than your spouse violates the exclusivity of the vows and the meaning of faithful monogamy. Moreover, surrogacy divides women up into separate zones for exploitation: the vagina, the ovaries, the uterus, the heart and mind where the baby-mother bonding is formed. Divided up.
Surrogacy requires a psychologically "surgical" detachment between the baby and the mother who carries him in her womb. It amputates baby-mother bonding, or --- to use another analogy --- it starves it to death. It separates childbearing from maternal bonding, and thus separates the maternal womb from the maternal heart.
No way good intentions can justify bad actions. Surrogacy is de-personalization from the git-go: it intentionally, by plan, denies the baby's right to his primordial maternal bond, and leaves a wound on the soul of the deliberately-bereft gestational mother.
It doesn't matter if the person solicited to the scheme of mothering-without-mothering is paid or unpaid, an employee, a family member, a fertility clinic specialist or your former girlfriend. It's de-personalizing per se.
I must say I admire both your clarity and your restrained passion. If you are not still writing for publication, you should be.
Very thoughtful and profound.
Thank you.