Preimplantation Genetic Diagnosis (PGD) for Pregnancy
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Mar. 6, 2013 - A recent study featured in the British Journal of Obstetrics and Gynecology found that the number of multiple births affected by birth defects doubled in the last 30 years. The study also found that within the European population studied, there was an approximately 50% increase in multiple birth rates. The study (visit
http://www.bjog.org/view/0/index.html), conducted by the European Surveillance of Congenital Anomalies (EUROCAT), was based on data collected between 1984 and 2007.
The primary reason for the rise in multiple pregnancies and birth defects is the adoption of in-vitro fertilization services by older women. Looking at the age ranges of women giving birth following fertility treatments over the last 25 years since in vitro technology became more widely available, the biggest increase of IVF patients has occurred in women in their late 30’s and early 40’s. Many of these women elected to postpone pregnancy until later in life for personal and professional reasons. It is a well-established biological fact that advancing age increases the chance of chromosomal abnormalities and birth defects due to declining egg quality. The chances of birth defects also increase with multiple births- a frequent complication of IVF.
Dr. John Jain, a leading IVF expert and head of world-renowned Santa Monica Fertility Center , describes the statistical changes, explaining, “Although there has been a rise in the number of birth defects and abnormalities, technology is catching up. Chromosomal testing methods are being adopted that can test an embryo even before implantation. One such method is Preimplantation Genetic Diagnosis (PGD).” (visit
http://www.santamonicafertility.com/fertility-and-treatme... for details) PGD can accurately identify a chromosomally normal embryo helping to alleviate both multiple pregnancies and chromosomal abnormalities by transferring only one embryo back to the uterus (SET – single embryo transfer). Dr. Jain added, “Early non-invasive prenatal diagnosis is now available by testing the mother’s blood for fetal DNA. Common trisomies such as Trisomy 21 (Down’s Syndrome) can be detected in this manner reducing the need for invasive tests such as amniocentesis or chorionic villus sampling.” The doctor further explained that although this test doesn’t alleviate the risks of birth defects it does give an early warning that the fetus might be affected. Jain notes that the EUROCATS study clearly confirm an increase in birth defects in cases of multiple births. This is primarily due to the use of IVF and the transfer of multiple embryos especially in women over 35. “However,”
Dr. Jain theorizes that, “as new technologies such as PGD and single embryo transfers become more common, we can most likely expect to see less multiple births and chromosomal abnormalities in children, even from mothers of advanced maternal age.”
Photo:
http://www.prlog.org/12093646/1
