In the field of human reproduction, it’s impossible to avoid the topic of genetic testing. At HFI, we offer many types of genetic testing and we want to help patients understand the different types of tests that we may recommend for you.
Genetic screening at your first visit
At HFI, we will provide preconceptional patients to all of our patients who come in for consultation. At your first visit with us, all patients will be offered the opportunity to be screened for recessive genetic diseases which is as easy as a simple blood draw and swabbing your cheek cells. In the world of genetic conditions, there are some diseases known as recessive conditions which will most commonly occur if both parents are carriers of a specific disease. If both sets of patients are carriers, there is a 1 in 4 chance a child will be affected with this condition. Since carriers of recessive disease are healthy, most patients won’t know about their condition unless they have already delivered an affected child. Because recessive diseases can be very severe, it is standard of care for all OB/GYN doctors to offer pregnant patients genetic screening early on in pregnant. The pitfall of this approach is if a woman finds out she is a carrier when she is already pregnant, her options become more complicated. For this reason, we want to empower our patients with the information to make the best decision possible before they become pregnant so they can start off pregnant as healthy as possible.
Preimplantation Genetic Screening (PGS)
One of the most common reasons unsuccessful IVF cycle or miscarriage is that the embryos placed into the uterus are genetically abnormal. Historically, this was avoided by choosing only the most normal appearing embryos to transfer. However, fertility specialists have noticed that there is not a perfect relationship between how an embryo looked at the time of transfer and whether or not a child was born genetically normal at the time of delivery. Over the last 15 years, genetic technology has advanced leaps and bounds. Fertility specialists are now able to biopsy embryos and determine whether or not they carry the correct amount of chromosomes (DNA) before transferring the embryo back into the uterus. Although there are many names for this test, it is most commonly referred to as preimplantation genetic screening (PGS). Because PGS involves the direct testing of embryos, PGS can only be offered during an IVF cycle.
While some patients will opt for PGS simply because higher IVF success rates, your doctor may also recommend PGS for many other reasons such as:
- Desire for maximizing success rates during IVF
- Advanced maternal age (>35)
- Patients who have experienced recurrent miscarriages
- Multiple IVF failures
- Desire to limit number of embryos transferred
Because this technology is so powerful, PGS also has the ability to tell you and your doctor the gender of the embryo prior to transfer. In our experience, some patients want to gender while others do not.
PGS during IVF is generally a helpful procedure so your doctor is likely to recommend it for you to maximize success rates with each IVF cycle. If you have questions about PGS and want to know how it can fit into your plans for parenthood, contact us for a consultation today.
Preimplantation Genetic Diagnosis (PGD)
Occasionally, we meet patients who carry genetic diseases. It’s important to know that carriers of genetic disease are oftentimes healthy and would only know they are a carrier if they have been screened or have affected family members. Amongst the different types of genetic disease, some conditions are recessive which usually means that carriers are healthy and patients wouldn’t know about their carrier status unless they were to be screened or have an affected child (cystic fibrosis, sickle cell, tay sachs). Other types of conditions are dominant, meaning it is more likely for patients to have multiple affected family members such as in the case of recurrent breast or ovarian cancer (BRCA1 and BRCA2 mutations), colon cancer (Lynch syndrome), Huntington’s disease, Marfan’s syndrome, among many others. Still others may be the first in their family to developed a brand new genetic mutation.
Each patient’s risk for genetic disease depends on a variety of factors such as your personal medical history, your family history and your ethnic heritage. In order to help you make the right decisions, our doctors at HFI will talk to you about your risk for genetic disease and may recommend any number of specific tests for you.
In the past, there was no way of helping patients besides educating patients on their pre-pregnancy risk of conceiving an affected child and then offering pregnant women invasive testing once they became pregnant (amniocentesis or chorionic villus sampling). Fortunately for our patients, fertility treatments now give patients the power of choice and planning. At HFI, patients who have or carry genetic illnesses may be able to have an unaffected child through the use of in vitro fertilization (IVF) with preimplantation genetic diagnosis (PGD). To undergo the PGD process, your doctor needs to identify the condition that you and your partner are carrying and a genetic probe needs to be made in the laboratory. Once the probe is made, the standard IVF process begins which starts with ovarian stimulation, followed by the fertilization of egg with sperm. Embryos are grown and then biopsied at the blastocyst stage. The biopsy sample is then genetically analyzed with the probe and the embryos the genetically healthy can then be identified and then transferred back into the uterus at a future date. To date, HFI has helped hundreds of patients who have severe genetic disease become parents of healthy children.
Whatever the case may be, our team of fertility and genetic specialists can help. Read about our list of testable genetic diseases here.