For years, expectant parents have relied on ultrasounds to find out the sex of their unborn baby.
 
But now, technology allows them to pick the sex of their child before he or she even enters the womb – a development that ethicists warn could have grave moral consequences.

Sex selection of human embryos orders a fertility company to "deliver a product" rather than a human child, said Dr. John Brehany, an ethicist and director of institutional relations at the National Catholic Bioethics Center.

Also, these companies are "ultimately taking actions to simply throw out" and "discard human beings," which is fundamentally wrong, he told CNA.

Many expecting parents find out the gender of their unborn baby through an ultrasound screening, or through methods of prenatal testing that can determine the gender of a baby as early as 7 to 10 weeks gestation.

However, more and more couples are opting not just to find out the gender of their baby, but to actually determine whether their next child will be a boy or a girl, through the process of "family balancing."

Procedures can cost into the tens of thousands of dollars. Couples might want a boy to carry on the family name or parents of two boys might want a baby girl badly enough to spend $100,000 and endure multiple assisted reproductive procedures to have one, as one couple did.

Advances in assisted reproductive technology have made this more possible, combined with in vitro fertilization where the human embryo – fertilized in a lab – is implanted in the mother's womb.

Technology like pre-implantation genetic screening can ensure that a human embryo is of the desired sex and free from unwanted genetic abnormalities. To better ensure a "successful" implantation, multiple human embryos may be implanted in the mother.

This is done "in the expectation that some embryos will be lost and multiple pregnancy may not occur," the Congregation for the Doctrine of the Faith stated in its 2008 document Dignitas Personae. "In this way, the practice of multiple embryo transfer implies a purely utilitarian treatment of embryos."

The practice is on the rise in the U.S. A 2006 Johns Hopkins survey of U.S. fertility clinics showed 42 percent of clinics that conducted pre-implantation genetic screening offered it for non-medical sex-selection purposes.

Anna Higgins, an associate scholar at the pro-life Charlotte Lozier Institute who just authored a report on sex-selection abortion, thinks there has been a notable increase in the use of the practice, based on doctors' statements and the number of clinics advertising gender selection and family balancing, as well as their "commercial success."

But according to decades of Catholic moral teaching, sex selection and in vitro fertilization are clearly wrong, Dr. Brehany said.

"First and foremost, it separates procreation from incarnated marital love," he told CNA, noting that the human embryo is created from sperm and an egg from the father and mother in a lab, outside the marital act. "It separates procreation from the manner in which God has designed human beings to come in to being, which should be in an actual act of marital love."

Also, he added, gender selection through assisted reproductive methods "almost instantly subjects the child to the standards and sort of the pressures, if you will, of production, and of producing an object."

Pre-implantation genetic diagnosis for sex selection, he explained, involves pulling a cell out of a human embryo or zygote to run tests for its gender. This can not only endanger the human embryo, but if it is selected for implantation, the other human embryos that have been created are at risk of being discarded, frozen, or experimented upon.

Clinics are being paid to "deliver a product" according to the customer's wishes, he said of the process, and are ultimately taking actions to simply throw out or otherwise discard human beings, and that's profoundly problematic."

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Dignitas Personae makes it clear that in vitro fertilization is wrong: "The Church moreover holds that it is ethically unacceptable to dissociate procreation from the integrally personal context of the conjugal act: human procreation is a personal act of a husband and wife, which is not capable of substitution," the document stated.

It also lists some of the evils resulting from the procedure – foremost the destruction of other embryos in the process, being discarded, frozen, or experimented upon.

"The blithe acceptance of the enormous number of abortions involved in the process of in vitro fertilization vividly illustrates how the replacement of the conjugal act by a technical procedure – in addition to being in contradiction with the respect that is due to procreation as something that cannot be reduced to mere reproduction – leads to a weakening of the respect owed to every human being," the document says.

Ultimately, these assisted reproductive options used for sex selection "the Church would view as no better than abortion, and in some respects worse," Brehany said.

"You're picking one [embryo], you're throwing out the others, and you're doing this outside the context of marital love, which in some respects makes it worse [than sex-selective abortion], not better."

Even the American Society of Reproductive Medicine admits that non-medical sex-selection is "controversial."

Some of the arguments raised against it, the society noted in a 2015 ethics report, are that "long-term risks" to children might exist and that further evaluation needs to be done on the matter, along with the concern that parents will not be showing "unconditional" love to their children who deserve it.