Do Surrogate Mothers Pass on DNA?

May 18th, 2018
ConceiveAbilities - Do Surrogates Pass on DNA?

DNA and Gestational Surrogacy

Modern families are, in many ways, modern miracles. It’s only in recent decades that infertility treatments allow couples to become parents with the help of a third party.

In some cases this means utilizing an egg or sperm donor, someone who can provide genetic material if it is not otherwise available from the intended mother or father. Other situations require a surrogate; someone who can carry the baby for the intended parents.

But are surrogate mothers biological mothers?

This is a fairly common question, and the general answer is no. In a gestational surrogacy arrangement with a gestational carrier, the baby’s DNA comes from the intended mother or egg donor, and intended father or sperm donor.

The Surrogacy Process

In most surrogacy arrangements in the United States, a previously fertilized embryo from the intended parents is transferred to a surrogate. Still, some wonder if the surrogate’s blood passes through the heart of the fetus and, if so, does that mean she is, in turn, passing on her DNA? And this question remains: is a surrogate mother related to the child?

The short answer is no: the baby has its own blood flowing through its veins and, ultimately, the DNA of the egg and sperm it was created from.

After the embryo successfully implants in the gestational carrier’s uterus, it continues to grow there. Also developing in the uterus is the placenta. This is an incredibly important part of the pregnancy because it not only nourishes the growing baby, but it also functions as a filter. It only allows certain things to cross through, acting as a gatekeeper to prevent DNA from passing between the baby and surrogate.

Studies now show that cells actually can cross the placental barrier and introduce the surrogate’s DNA to the baby, or vice versa. But is it enough to impact the baby’s genetic makeup? Will the baby look like the surrogate mother? Absolutely not. There is not nearly enough DNA passing through the placenta to impact the child; the placenta is a truly effective filter.

Traditional Surrogacy and Rare Exceptions

There are still some rare cases of traditional surrogacy, in which the baby is either conceived traditionally or the surrogate undergoes artificial insemination. In these situations, the surrogate’s egg is used and the child would have half her DNA. This is what leads people to wonder if surrogate mothers have rights to the baby. The fact is that if she is genetically related to the baby through her egg, it can complicate the situation. Due to these ethical and legal ramifications, traditional surrogacy is a rare practice.

Nature and technology continue to work together in unique ways – family building is no exception. To learn more about how surrogacy works, this blog post will be helpful. If you’re ready to start the process, please contact us today.