Oocyte cryopreservation is a technology that has helped many women undergoing in vitro fertilization. The technology allows for the extraction, freezing, and storage of their oocytes for future fertilization and transfer. It allows women to fertilize only as many eggs as they need for an IVF cycle without developing excess embryos and facing the ethical challenge of disposing of them.
The data on pregnancy rates for oocyte cryopreservation are encouraging. Fertilization and pregnancy rates for egg donation cycles using cryogenically preserved oocytes are similar to cycles using fresh eggs. Additionally, a recent compilation of research studies on egg freezing has found that babies born due to oocyte cryopreservation do not demonstrate an increased chance of having congenital abnormalities over their naturally conceived counterparts.
Oocyte cryopreservation is still an advancing technology, but at the same time, it is no longer considered experimental.
Pre-implantation Genetic Diagnosis is one option to consider during an IVF cycle involving oocyte cryopreservation. Much like prenatal diagnosis, PGD is the genetic profiling of embryos before implantation. It can be used to screen for specific genetic diseases, such as single-gene disorders and even X-linked and mitochondrial disorders.
Transferring only the most healthy and viable embryos to the uterus eliminates the chances of selective termination of pregnancy in the future and increases the chance of giving birth to a healthy baby.
PGD also allows for the diagnosis of late-onset diseases and predisposition to cancer, as well as the presence of disease or disability such as deafness, which is particularly useful if the mother or father has a family history of relevant illnesses.
PGP is largely justified for women of advancing maternal age (over 35 years of age) or who have undergone repeated failed IVF cycles. The screening for detecting chromosomal abnormalities such as aneuploidy, chromosomal inversions, and deletions can help shed some light on why previous IVF cycles had failed.
After implantation, there are also common prenatal screening and diagnosis that are important components of prenatal care. This includes first-trimester exams such as Fetal Cells in Maternal Blood and Cell-free fetal DNA in Maternal Blood tests, which are both non-invasive methods in the diagnosis of aneuploidy and such diseases as Down Syndrome, Edwards Syndrome, and Patau Syndrome
Prenatal examinations are also important later in pregnancy. During the second trimester, less invasive screening exams such as maternal serum alpha-fetoprotein and beta-HCG can be used to screen for other deformities such as neural tube defects.
During the third trimester, fetal well-being can also be monitored using the non-stress test, which monitors the frequency of accelerations and decelerations of fetal heart rate.