Most babies are born healthy, but 3-5% have a birth defect or problem with development. Some of those problems happen by chance, and some can be inherited. For those building their family through egg or sperm donation, how can a genetic counselor help to avoid the risks? We talked to Amy Vance, of Bay Area Genetic Counseling about her role in the fertility journey and how genetics and family health history play a role in the journey to becoming a parent through egg donation.
What is a Genetic Counselor?
Genetic counselors are masters-trained licensed health professionals with expertise in the science of genetics who are trained to translate technical and complex science and research into user-friendly terms for patients and providers. Genetic counseling is not the same thing as genetic testing.
With the vast amount of genetic information and testing available, Genetic Counselors are an invaluable resource for the IVF clinic However, one basic component of risk assessment before a pregnancy for all gamete providers that’s important, and often overlooked, is the family history evaluation.
Family history is the cornerstone of the genetic risk assessment. A thorough family history evaluation by a Genetic Counselor provides the foundation for evaluating risks for genetic conditions and offering appropriate testing before undergoing fertility treatment and before a pregnancy occurs.
What happens when an egg donor meets with a genetic counselor?
First, the donor will complete a health questionnaire through her agency. Collecting family health history involves asking questions about a person’s health and their family. Most people have family members with different health issues, some of which can be inherited. Most of these inherited genetic conditions are not detectable by standard genetic screening done by fertility clinics. For an egg donor cycle, both the egg donor and the sperm contributor may provide this information.
Next, the questionnaire is reviewed by the genetic counselor
Taking a detailed family history helps ensure that important genetic information is not overlooked and that any appropriate testing and/or information is provided to the patient or donor prior to pregnancy. Guidelines from the American Society for Reproductive Medicine (ASRM) suggest a review of personal and family history of genetic disease and prior genetic test results that may affect the course of treatment, with patients being counseled about additional genetic testing that may be indicated before starting treatment relating to their personal or family history.
Genetics Consult
After the review of the questionnaire, the donor is provided with detailed instructions about the purpose of the consultation, how to prepare, and some tips about talking with family members. I’ll schedule a call with her and we’ll have the Genetics Consult. Family history risk assessment for ovum donors by a genetic counselor provides a thorough, standardized method of screening ovum donors. This is a really important step because the consult, combined with the health questionnaire, identifies at least 20% more important family history information. One reason is because of the preparation and instruction given to the donor prior to the consult. The conversational nature of the consultation allows for additional information to be requested as needed. I may ask her to follow up with family members to gather more information based on what comes up during our session. Occasionally I may even request a medical document on a family member if there is a condition that requires that level of detailed evaluation.
But I had Genetic Carrier Screening, isn’t that enough?
There is a misconception that genetic carrier screening panels take the place of a family history. The family history seeks to identify actual conditions that may run in a family that increase the risk to offspring. The genetic carrier screening is for hidden genetic traits and is used for matching purposes. Most of the diseases on the carrier screening panels are recessive, and carriers for most recessive diseases don’t have symptoms- that is why the testing is used. Conversely, family history can’t identify which recessive traits a person carries. There are other patterns of inheritance such as autosomal dominant (when only onegenetic parent is a carrier and therefore there is a 50% chance of the child inheriting thegene) and multifactorial (inheritance pattern involving multiple genes - most common diseasesare inherited this way -there is a risk to close relatives of affected individuals) which the familyhistory is meant to capture since these can confer a risk to offspring.
Real Life Cases
As the following cases demonstrate, implementation of a routine genetic counseling screeningprogram for all egg and sperm donors is an important step in identifying possible genetic riskfactors that may be present in the donor’s family so that the intended parents have anopportunity for informed decision-making about potential genetic risks prior to donor selectionand pregnancy.
Case 1: A 5-time egg donor was referred by a clinic for genetics consult (family history assessment by genetic counselor). During the consultation, it was discovered that the donor’s maternal grandmother and maternal great grandmother have a genetic eye disease. The donor’s mother is too young to have symptoms appear and there has been no genetic testing in the family and the mother has not been evaluated. This condition follows an autosomal dominant inheritance pattern and there is an increased risk to the donor’s offspring. According to the ASRM criteria, she is not considered an ‘eligible’ donor (IPs can still choose to use the donor after comprehensive genetic counseling). The donor asked me, “why is this the first time I am having the genetics consult? Why have I been allowed to donate 5 times before and this has never come up?” The answer is that the consult was not required as part of the other donations. Unfortunately, now the previous intended parents must be informed of this new information and the potential risk to their offspring. This puts everyone in a difficult position that could have been avoided had this information been available from the beginning.
Case 2: A Donor’s paternal uncle has a brittle bone disorder, diagnosed as a teen, causing over 20 broken bones. This condition is autosomal dominant and can be highly variable even within a family. Some people have symptoms that only a trained geneticist may identify, but even mildly affected people can have more severely affected offspring. The donor’s father has not had a genetics evaluation and there has been no genetic testing done in the family. As in the case above, this condition is autosomal dominant and there is an increased risk to the donor’s offspring and by ASRM criteria, she is not considered an ‘eligible’ donor. The question from the agency was, “why don’t we screen for dominant conditions (by genetic testing).” Genetic testing for dominant conditions is not part of carrier screening, because that would be ‘diagnostic testing’, since people with a single mutation for a dominant condition are ‘affected’. That is not the purpose of genetic carrier screening for egg donors but it IS the purpose of the family history.
As a side note, none of the information above was included in the donors’ profiles. This information became available as a result of the targeted follow-up and detailed information requested as part of the genetic consult. Most of the time the donors don’t know this information about their own family until the consultation process is complete.
Is a genetic consult with a genetic counselor required?
A genetic consult is not always required but I feel it's good practice. I think that many clinicians don’t understand the value of family history evaluation and there is an ongoing misconception that carrier screening identifies all risks to offspring. Additionally, there is a cost for genetic counseling, but it is minimal. In my practice a donor family history is $325. The turnaround time for the reports is less than a week. If the consult is factored into the overall cycle as part of routine screening, there is no time delay. Even if the clinic does not require the genetics consult, if the intended parent feels it would be desirable they can always request it.
References:
Family history risk assessment by a genetic counselor for ovum donors: data for 582 in house ovum donors from a single clinic demonstrates its value. Amy Vance, MS, LCGC fertstert.org
Family history by a genetic counselor is a critical step in screening all patients in the ART clinic. Amy Vance, MS, LCGC www.ncbi.nlm.nih.gov
The importance of family history risk assessment in the infertility setting. Fertil Steril. 2005;84(Supplement 1):S125. doi: 10.1016/j.fertnstert.2005.07.305. [CrossRef] [Google Scholar] Vance A, Zouves C.
Family history risk assessment: data for 723 consecutive ovum donors from a single agency demonstrates the value of the genetics consult. Fertil Steril. 2011;96(3):S218. Vance A. doi: 10.1016/j.fertnstert.2011.07.839. [CrossRef] [Google Scholar]
Amy Vance is a licensed, board-certified genetic counselor in practice for 32 years. She founded Bay Area Genetic Counseling in 2001, a boutique private practice focusing primarily on serving couples and egg donors pre-IVF, but also offering cancer risk assessment and genetic counseling for other genetic indications. Her passion has been continuing to educate providers about the value of genetic counseling in the ART practice, focusing specific attention to family history. She has authored several articles and abstracts and delivered dozens of invited presentations on the topic of the importance of family history for egg donors and couples preconceptionally, genetic testing and carrier screening, cancer risk assessment, and preimplantation genetic testing.