Medical and Genetic Considerations

Choosing a donor can be an emotional experience. It’s also one that requires some solid information to help you make your decision. Learning more about a donor's medical background and genetic testing is a great place to start.

During approximately a three- to six-month period, our team of trained and certified experts perform the physical, medical, genetic, and psychological evaluations (including regular testing of sperm and blood samples) of applicants to help ensure they are up to California Cryobank® donor standards.

CMV (cytomegalovirus) is a virus that initially presents as a mild cold, with symptoms resolving quickly. Many people who contract CMV are never symptomatic and most don't even know whether they have ever been infected. Exposure to this virus is quite common, with about 50% to 85% of people in the U.S. having CMV at some point in their life. It typically doesn’t cause problems in healthy people. But in a small number of cases, it can be a risk for a developing fetus. For that reason, FDA, AATB, NYS and Health Canada regulations and standards require us to test all our potential donors to ensure they do not have an active infection. Donors listed as "CMV positive" have blood work showing a remote (past) infection, but not an active infection at the time of donation.

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Medical and genetic updates

We ask our donors to keep us updated on their personal and family medical histories. Our genetics team may notify you about significant donor updates if the information could be relevant to your child's health. You can also call or email us to ask about any updates regarding your donor.

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Medical and genetic updates

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For many families, the donor’s blood type is an important part of deciding on a donor.

Rh negative

The donor's blood type may be medically important to consider if the person carrying the child is Rh negative (Rh-). These individuals may develop antibodies to a fetus that is Rh positive — which could be the case if either the egg or sperm source is Rh positive.

Matching blood types

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Every child (regardless of whether they were conceived with or without assisted reproductive technologies) has a 3% to 4% chance of having a birth defect.It’s impossible to eliminate these risks or test for all of them before becoming pregnant. However, a genetic risk assessment is performed on California Cryobank's donor applicants as part of the donor qualification process. The goal of the risk assessment is to try to reduce the risk for significant medical problems in the donor-conceived children. If a donor applicant has a significantly increased risk (above the 3-5% risk of the general population), of having children with a major birth defect, the donor would not be suitable to participate in our donor program.

A genetic test summary (GTS) tells you which specific tests were performed on a donor and the results of those tests. Our reproductive genetic specialists are available to discuss the tests performed on your donor, the test limitations, and additional testing options you may want to consider. For more information, please contact us.

Genetic tests and technologies are continuously being developed and improved. These new developments may lead to changes in the genetic testing that we perform on our sperm donor applicants. In most cases when we add new genetic tests to our screening process, the tests are performed on new donor applicants. The new tests are not performed retrospectively on retired donors. Therefore, not every donor who has vials available for purchase has had exactly the same genetic testing.

Each moment in this process matters. We’re here to walk you through it all — from the biggest “what ifs'' to the smallest “but hows.”

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Discover more resources

Check out our valuable resources to help you learn more about using donor sperm for your family building.

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