Abstract
Dear Madam,
The wide variety of international legal responses between, and even within, countries to the new realities of assisted conception is fascinating. 1 The temporary, dependant and life-sustaining relationship of the fetus to the host pregnant body is further complicated when there is no genetic connection (as in donor or bought egg arrangements) or no intent to breast feed or bring up the child after birth (as in surrogacy). However, it is wrong to state that “the baby has the blood of the birth mother in him/her” as if the mother's blood circulated around the baby's body. This is biologically incorrect and might mislead readers who place ethical, moral or religious value on “blood relationships”. From early on, the fetal heart pumps its own red cells around its own body and through the cord and placenta. The mother respires, feeds, metabolises and excretes for the developing baby, but they have two separate circulations albeit situated closely entwined within the placenta and exchanging gases, nutrients, antibodies and occasional cells. The ability of a normal pregnant woman not to reject a fetus that is 50% genetically and immunologically different from her (as in host-versus-graft transplantation reactions) continues to confound scientists. It is known that women who are 100% genetically unrelated to their fetuses (egg recipients and full surrogates) are at significantly higher risk of hypertensive disorders of pregnancy and specifically life-threatening early onset pre-eclampsia. 2 Whilst this important obstetric implication may have little legal traction, it adds another dimension to our understanding of the disbursement or displacement of risks.