Prenatal tests assess the risk or the presence of chromosomal abnormalities in a fetus. Copy number variation or chromosomal imbalances (amplifications or deletions) can have devastating effects on a pregnancy—even causing loss of the fetus.
Another focus in prenatal testing is the risk assessment and diagnosis for Down syndrome (DS), which has an incidence of 1 out of 800 to 1 out of 1,000 births. Risk probabilities for DS increase with advancing maternal age and as women are delaying their first pregnancy until later in life these days, prenatal testing will become an even more important measure for concerned parents-to-be.
Currently, genetic testing on the fetus involves sampling material by amniocentesis or chorionic villus sampling (CVS). Due to the slight risks of miscarriage and potential complications associated with both procedures, maternal blood tests were developed to screen the larger population for the at-risk subset that should have an invasive procedure performed for conclusive diagnostic testing.
Clinical publications report a reduction in the number of invasive procedures conducted as a result of prenatal screening practices. Concurrently, detection rates for DS have improved, likely as a result of these effective prenatal screening algorithms.
U.S. prenatal testing was a $1.3 billion market in 2010. Prenatal screens provided 75% of revenues, and prenatal diagnostic testing generated the remaining 25%. Considering that 60% to 70% of the 5 million births in the U.S. receive prenatal care, the screening segment would be large relative to the diagnostic segment. However, the clinical utility of microarrays and sequencing in prenatal applications will lay the foundation for tremendous growth in the prenatal diagnostic segment.
The much anticipated commercial launch of noninvasive prenatal diagnostics (NIPD) in 2012 will bring to market a diagnostic-level analysis of rare fetal cells and nucleic acids circulating in maternal blood. The NIPD competitive landscape includes Verinata Health, Sequenom, LabCorp (Genzyme Genetics), QuantaLife, Ravgen, and Novartis/Fluidigm.
The exciting technological developments in the prenatal diagnostic segment make this one of the most anticipated clinical diagnostic segments, which will contribute to the long-term health of prenatal testing markets.
Market restraints in prenatal testing include slightly falling fertility rates, conservative action by the influential American College of Obstetricians and Gynecologists, and the individual attitudes of patients in their choices for prenatal care.
Key market participants include PerkinElmer, LabCorp, and Quest Diagnostics. Market share is quickly captured by clinical companies through acquisition of specialty prenatal testing service providers.
Preimplantation genetic diagnosis (PGD) is a lesser known application area for genetic technologies. PGD is the genetic analysis of embryos that are produced by in vitro fertilization (IVF) cycles. PGD testing is done prior to implantation to help select the embryos for implantation that are free of inherited genetic disorders.
PGD screening of embryos for aneuploidy will be a major growth application since approximately half of the cases of embryonic loss within assisted reproductive technology (ART) are associated with aneuploidy.
Of the total PGD testing in the U.S., 78% search for chromosomal abnormalities such as aneuploidy, translocations, and gender determination. The remaining 22% of PGD testing search for single-gene mutations and human leukocyte antigen (HLA) typing.
HLA typing is a critical factor for biological compatibility between a donor embryo and a sibling. Chromosomal analysis is more frequent because some aneuploidy detection by fluorescence in situ hybridization has been reimbursed and also because couples that are undergoing IVF cycles have less awareness of the ability to test for single-gene mutations.
The 8,000 PGD cases per year include chromosomal and single-gene mutation analysis. ART couples that use PGD must add thousands of dollars in addition to the cost of an IVF cycle and PGD fees, which are usually paid out of pocket. The size of the U.S. PGD market is less than 2% of the U.S. prenatal testing market since it is still considered experimental.
In the long term, prenatal testing and infertility associated service markets like PGD will be in demand as women are delaying motherhood. The market stages range from relatively mature (prenatal screens), growing (prenatal diagnostics), and early stage (PGD).