Compiling your medical family tree

Your family medical history, sometimes called a medical family tree, is a record of illnesses and medical conditions affecting your family members. Here's why a family medical history comes in handy — and how to create a family medical history of your own.

How is a family medical history used?

You inherit half of your genetic profile from each parent. Along with the genetic information that determines your appearance, you also inherit genes that might cause or increase your risk of certain medical conditions. A family medical history can reveal the history of disease in your family and allow you to identify patterns that might be relevant to your own health.
Your doctor might use your family medical history to:

• Assess your risk of certain diseases
• Recommend treatments or changes in diet or other lifestyle habits to reduce the risk of disease
• Determine which diagnostic tests to order
• Determine the type and frequency of screening tests
• Determine whether you or family members should get a specific genetic test
• Identify a condition that might not otherwise be considered
• Identify other family members who are at risk of developing a certain disease
• Assess your risk of passing conditions on to your children

A family medical history can't predict your future health. It only provides information about risk. Other factors — such as your diet, weight, exercise routine and exposure to environmental factors — also affect your risk of developing certain diseases.

What's the best way to gather family medical information?

Your family might want to work together to develop a family medical history. Consider kicking off the project at a family gathering, such as a holiday or reunion. Keep in mind, however, that some loved ones might be uncomfortable disclosing personal medical information — perhaps due to guilt, shame or a reluctance to face painful memories.
If you encounter reluctance, consider these strategies:

• Share your purpose. Explain that you're creating a record to help you determine whether you and your relatives have a family history of certain diseases or health conditions. Offer to make the medical history available to other family members so that they can share the information with their doctors.
• Provide several ways to answer questions. Some people might be more willing to share health information in a face-to-face conversation. Others might prefer answering your questions by phone, mail or email.
• Word questions carefully. Keep your questions short and to the point.
• Be a good listener. As your relatives talk about their health problems, listen without judgment or comment.
• Respect privacy. As you collect information about your relatives, respect their right to confidentiality. 

What other sources of information may be beneficial?

You might want to consult family documents, such as existing family trees, baby books, old letters, obituaries or records from places of worship. Public records — birth certificates, marriage licenses and death certificates — are usually available in county record offices. If you or your family members maintain electronic personal health records, use them.
If you're adopted, ask your adoptive parents if they received any medical information about your biological parents at the time of your adoption. Adoption agencies also might have family medical information on file. If you were adopted through an open adoption process, you might be able to discuss your family's medical history directly with members of your biological family.

What information should be included in a family medical history?

If possible, your family medical history should include at least three generations. Compile information about your grandparents, parents, uncles, aunts, siblings, cousins, children, nieces, nephews and grandchildren. For each person, try to gather the following information:

• Sex
• Date of birth
• Ethnicity
• Medical conditions
• Mental health conditions, including alcoholism or other substance abuse
• Pregnancy complications, including miscarriage, stillbirth, birth defects or infertility
• Age when each condition was diagnosed
• Lifestyle habits, including diet, exercise and tobacco use
• For deceased relatives, age at the time of death and cause of death

Pay special attention to conditions that develop earlier than usual, such as high blood pressure in early adulthood, or conditions that affect multiple relatives.

How should the information be compiled?

Once you've gathered information about your family, create a diagram that visually depicts the relationships among family members. Record medical information and other details about each person on your tree. If information about a disease or cause of death is unknown, don't guess at the answer. An incorrect guess can result in a poor interpretation of your medical history. Don't worry if some details are missing.
Give your doctor a copy of your family medical history and ask him or her to review it with you. Your doctor might ask you questions for clarification and can help you interpret the relevance of certain patterns in your medical history, including the need for preventive measures or screening tests. Going forward, update your family medical history every couple of years. Be sure to share updates with your doctor.