When an expectant couple suffers a miscarriage, it is devastating, not only for the loss of the pregnancy, but also not knowing why it happened.
While many assume the miscarriage happened because of something wrong with the pregnancy, most of the time there was something wrong with the embryo itself.
Chromosomal abnormalities are the main cause of miscarriages. A woman is born with all the eggs she’ll have in her lifetime, and, as she gets older, her eggs do too. With the aging of the eggs, the incidence of abnormal chromosomes goes up, making the embryos nonviable. There also is another abnormality that can cause miscarriage, in what’s called a “balanced translocation,” in which pieces of the chromosome have swapped spots.
Testing for chromosomal abnormalities tells doctors what’s going on with the chromosomes inside cells, both within the parents as well as in the embryos or miscarried tissue itself. In very complex cases, doctors use whole exome sequencing on the parents. Embryos can be tested this way as well.
The woman or the couple will go through the IVF process to produce embryos, and those embryos are screened to ensure they don’t have any abnormalities, such as missing or extra chromosomes. The abnormal embryos are discarded and only the healthy unaffected ones will remain to be put back into the uterus.
This process is expensive and lengthy. Now experts want women to know there’s new testing that can help them get answers faster.
Dr. S. Zev Williams, chief of the Division of Reproductive Endocrinology and Infertility and associate professor of obstetrics and gynecology at Columbia University Medical Center, and his team have been working on new technology to get test results faster.
A handheld DNA sequencer can make genetic screening of these cells or tissue more accessible, and at a fraction of the cost. Instead of waiting weeks for test results to come back, they could have answers that same day.
“It allows us to do very, very rapid DNA sequencing and can be used to pick up chromosomal abnormalities and genetic mutations, and what we sequence depends on the clinical need,” Williams reports, “[DNA] can come from embryos where a couple of the cells are plucked off from the embryo, and that’s what’s used on the sequencer, but the other area where we use it would be miscarriage samples and CCS (comprehensive chromosome screening) samples.”