Preimplantation genetic testing raises important concerns related to whether and when it should be used, its safety and effectiveness, costs and access and what it would mean to live in a society where one’s genetics become more a matter of choice than chance. These are complicated dilemmas about which there has been little discussion or opportunity to form agreement.

The extent to which these issues command attention will likely be tied to how often and for what purpose preimplantation genetic testing is used. Since preimplantation genetic testing requires IVF, it is mainly used today by a relatively small number of parents who are willing to undergo IVF to avoid a known serious or fatal genetic condition or who are unable to get pregnant without IVF because of infertility problems. For the moment, one would expect very few people who otherwise have no problems achieving a healthy pregnancy to utilize preimplantation genetic testing. Nonetheless, that could change as IVF techniques improve and the number of genetic tests that can be employed successfully in preimplantation genetic testing increases.

The cost is another factor where there are concerns that it will end up being accessible and affordable only to the wealthy. As with all new medical treatments and techniques, the availability of preimplantation genetic testing will be influenced by a health care system in which cost-benefit considerations largely drive coverage. If there is to be widespread insurance reimbursement of preimplantation genetic testing, those who underwrite coverage mainly employers and insurance companies must view it as cost effective. Otherwise, the cost of test will be paid out-of-pocket by patients.

The global preimplantation genetic testing market based on application is segmented into aneuploidy, structural chromosomal abnormalities, single gene disorders, X-linked disorders, HLA typing and gender identification. Aneuploidy dominated the market in 2018.

Preimplantation genetic diagnosis (PGD) for aneuploidy testing represents the most common indication of PGD in IVF cycles. Preimplantation genetic screening (PGS) involves the analysis of embryos to identify changes in chromosomes copy number (chromosome aneuploidy), which would compromise embryo viability and will ultimately result in failed implantation or subsequent miscarriage. Most aneuploid embryos show very low implantation rates and those finally implanted usually undergo miscarriage during first trimester of pregnancy. Identification of aneuploid embryos allows only euploid embryos to be transferred to the mother, thus maximizing the likelihood of obtaining a successful pregnancy.

TECNALIA, a company in Spain has implemented Next Generation Sequencing (NGS) technology for the detection of chromosome aneuploidy in embryos from IVF cycles. This technology enables the analysis of 24 chromosomes in a single test with a higher resolution than previous technologies.

For single gene disorders, preimplantation genetic testing aims to identify, whether a specific embryo carries a DNA mutation responsible for single gene disorder, for which one or both parents are carriers, to prevent the transmission of heritable genetic disorder to their offspring. Before the mutation responsible of the family disorder is searched on the embryo biopsies, it may be necessary a pretest work up, in which parents and affected relatives are tested in order to rule out false positives and false negatives as a result of ADO (Allele Drop-Out). The NGS technology allows to simultaneously analyze more than 500 genes associated with single gene hereditary disorders.

North America accounted for the largest share of the global preimplantation genetic testing market in 2018. The US has been a lucrative market for preimplantation genetic testing.

In the US, IVF and PGD providers, together with patients, determine whether PGD is appropriate for particular indications or in particular situations. Although government oversight is limited, voluntary professional organizations are playing an increasing role in the oversight of PGD. The Centers for Disease Control and Prevention (CDC) requires IVF clinics to report a variety of data to the federal government on pregnancy success rates and noncompliant clinics are listed on the CDC’s website (there are no other penalties for failure to comply with the law). However, IVF clinics are not required to report the use of diagnostic tests such as PGD or the health status of babies born after the procedure.

The Food and Drug Administration (FDA) regulates drugs and devices, including those used in IVF treatments. However, the FDA does not regulate most genetic tests, and does not regulate those genetic tests used in PGD, there is no uniform system to assure test accuracy or validity. The Centers for Medicare and Medicaid Services (CMS) administers the Clinical Laboratory Improvement Amendments of 1988 (CLIA). CLIA’s requirements include standards and testing to monitor laboratory performance. CMS has taken the position; however, PGD is not covered by CLIA but rather ‘‘is an assessment of a product and therefore falls under FDA’s oversight of reproductive tissue’’. Thus, laboratories that perform genetic analysis for PGD are not subject to regulation as clinical laboratories under CLIA.

Human research subject protections are mandatory for research carried out at institutions supported with federal funds or research conducted to support an application to the FDA for product approval. However, because PGD involves embryos, it is not likely to be eligible for federal research funding nor to result in an FDA application; thus, PGD research largely falls outside federal requirements for protecting human research subjects.