In vitro fertilization (IVF) helps individuals or couples conceive by combining the egg and sperm outside the body in a laboratory setting. After fertilization, the resulting embryo is monitored for several days before being placed into the uterus to initiate a pregnancy. As reproductive technology advances, many prospective parents ask whether they can choose the sex of their baby. Selecting an embryo’s sex is scientifically possible through an add-on procedure performed before the embryo is transferred.
The Technology Used for Sex Selection
The scientific method for sex selection within an IVF cycle is Preimplantation Genetic Testing (PGT), specifically PGT-A, which screens for chromosomal errors. This testing involves an embryo biopsy, performed when the embryo reaches the blastocyst stage, typically on day five or six. A skilled embryologist removes a small cluster of cells (five to ten) from the trophectoderm, the tissue layer that will eventually form the placenta.
These biopsied cells contain the embryo’s genetic material and are sent to a specialized laboratory for DNA analysis. The lab identifies the sex chromosomes present: two X chromosomes (XX) indicate female, while one X and one Y chromosome (XY) indicate male. This highly accurate analysis allows the fertility specialist to know the sex of each viable embryo before transfer.
Medical Justification Versus Elective Preference
The motivation for sex selection falls into two categories, influencing the practice’s ethical and legal standing. The first is a medical justification, involving selecting a child’s sex to avoid passing on a sex-linked genetic disorder. Conditions like Duchenne muscular dystrophy or hemophilia are linked to the X chromosome and primarily affect male children. Selecting a female embryo reduces the risk of the child inheriting the disease.
The second, and more common, category is an elective preference, often called “family balancing.” This non-medical choice is sought by parents who already have children of one sex and wish to have a child of the opposite sex. The goal is to select a specific sex for the embryo transfer from the pool of healthy embryos created during the IVF cycle.
Global Regulations on Gender Selection
The legality of using PGT for elective sex selection depends heavily on geographic location, creating a patchwork of global regulations. Many countries have banned the practice for non-medical reasons, permitting it only when a sex-linked medical condition is a concern. For example, most of Europe, Canada, China, and India prohibit non-medical sex selection, often due to concerns about gender bias and the misuse of medical resources.
In contrast, the United States has no federal law prohibiting sex selection for family balancing, making it legal in most states. However, major medical organizations in the US advise that providing this service for non-medical reasons warrants “serious ethical caution.” Individual fertility clinics may also have their own policies allowing or prohibiting elective sex selection. Prospective parents must investigate both national laws and the specific guidelines of their chosen clinic.
Practical Considerations of Adding PGT to IVF
Adding PGT for sex selection introduces several tangible factors that impact the patient’s IVF experience. The most immediate consideration is the significant additional expense, typically adding between $3,000 and $6,000 to the total cost of an IVF cycle to cover the biopsy and genetic analysis.
The process also affects the timeline, as the embryos must be frozen while the genetic test results are pending, which usually takes one to two weeks. This necessitates a Frozen Embryo Transfer (FET) in a subsequent menstrual cycle, extending the overall time to a positive pregnancy test by approximately two to four weeks compared to a fresh transfer.
Furthermore, the embryo biopsy carries a small inherent risk, with a chance of one to five percent that the embryo may be damaged or fail to develop further after the procedure. Selecting only one sex also means that chromosomally normal embryos of the non-selected sex will be set aside, potentially reducing the total number of embryos available for future transfers.