IVF and Sex Selection

Determining the sex of an embryo was made possible by a process initially used to detect and prevent genetic disease called preimplantation genetic testing (PGT). Consequently, prospective parents take the opportunity to choose the sex of their child using PGT. 

In this article we shall be exploring the reasoning behind sex selection, the process of PGT, legalities surrounding sex selection, and the emotional implications of choosing a child’s sex beforehand.

Sex vs. Gender

‘Gender’ was the word previously used to speak about a person’s sex. Gender has now been understood to be more of a spectrum of identities. One study describes ‘sex’ as being based on biological factors, and ‘gender’ as being based on behavior, lifestyle, and experiences.

This shift then means that a child’s assigned sex at birth (ASAB) may change over time. Therefore ASAB is now used to address a person’s reproductive organs, chromosomal and hormonal makeup at birth. 

While PGT makes it possible to select the sex of an embryo, the gender identity that the child will assume cannot be predetermined.

Sex Selection Legality

In many countries across the world including Canada, India, China and most of Europe, sex selection is illegal, unless parents can medically demonstrate the necessity, such as avoiding passing down a genetic disorder. 

Although legal in America, sex selection is a practice that is highly scrutinized for its ethics. The American Society of Reproductive Medicine (ARSM) has expressed concern over how ethical sex selection is, but has not called for it to be outlawed.

IVF and Sex Selection

Since the 1990s, PGT has made it possible to determine the sex of an embryo before implantation. In recent years, this PGT opportunity has been increasingly used by prospective parents to choose the sex of the embryo. The availability of the opportunity to select the sex of a child beforehand however, presents a new set of challenges to these parents. 

Reasons for Choosing Sex

The leading reason for sex preselection is to prevent passing down diseases that are sex-linked. 

Some conditions are carried genetically on the X chromosome, and this can affect male embryos disproportionately because they only have one X chromosome. Whereas female chromosomes that have two X chromosomes could potentially leave the second X chromosome disease-free. 

Sex-linked diseases such as hemophilia, duchenne muscular dystrophy, red-green color blindness, and certain forms of high blood pressure create room for preselection to reduce or eliminate risk, for the sake of a healthy outcome. As a result, legally, this reason is prone to less ethical scrutiny than the other reasons prospective parents may have.

Non-medical reasons for preselection usually are around preferences such as  ‘family balancing’, where parents desire an equal number of children of both sexes, or desire a child of a specific sex because they only want one child. 

How Sex Selection Works

There are a number of PGT protocols used to identify an embryo’s sex with an accuracy of almost 100 percent. PGTs are performed in the IVF window between fertilization and implantation, where an embryo is allowed to develop for a few days outside the uterus. A tiny biopsy is taken after five days of the embryo’s development for genetic testing.

Preimplantation Testing for a Monogenic Disorder

PGT-M - or PGD - tests for single-gene disorders and has been very effective in identifying hereditary conditions such as cystic fibrosis, sickle cell anemia and Tay-Sachs disease.

Anomalies in DNA chromosomal count can also be detected by this protocol which is important because chromosomal anomalies are a leading cause of early miscarriage.

Preimplantation Testing for Aneuploidy

PGT-A is used to check for anomalies in the number of chromosomes within an embryo’s gene-pool. Not only can it identify the risk of miscarriage, it can also detect chromosome-related disorders like Down syndrome. However it cannot detect specific disorders in the way PGT-M tests can.

In Summary

It has been possible for decades to determine the sex of an embryo before implantation during IVF treatments, but it was done as a mitigative measure against sex-linked disorders and chromosomal diseases.

The recent influx of the use of PGT because of personal preference has raised many unanswered ethical questions. Many countries have outlawed elective sex selection for reasons other than medical necessity, while medical organizations in the US advise providers to exercise “ethical caution”.

Additionally, some fertility clinics have policies regulating preselection that is based on personal preference as opposed to medical necessity.

Frequently Asked Questions (FAQs)

What happens to unused embryos?

Unused embryos are either frozen for future use, donated if prospective parents do not want IVF treatments in future, or simply discarded as medical waste.

How much does it cost to choose the sex of an embryo?

Sex selection treatments cost between $1,000 and  $4,000. This is separate from the existing costs associated with IVF. Check with your health insurance provider which aspects of your fertility treatment your plan covers.

What sex are most IVF pregnancies?

PGTs have caused more male embryos to be implanted than female embryos. The differential being as large as 164 male embryos for every 100 female embryos implanted. 

Contact Us

If you are interested in sex selection as part of your IVF treatment, ensure that you check the guidelines for this at potential clinics before you begin treatment.

If you have further questions about starting a family, consult with the experts at Nevada Center For Reproductive Medicine. We are happy to walk this journey with you from any of our locations across the country.