Freezing eggs one way to preserve fertility after cancer

Q: My sister was diagnosed with cancer, and her doctors say she should consider freezing her eggs. It's not definite that the treatment will affect her ability to get pregnant, but it's a real possibility. I don't know how freezing one's eggs works. Can you explain? Is it expensive?

A: Unfortunately, it's true that certain medical treatments can, in addition to saving the person's life, adversely affect their future fertility. This can occur in both women and men. For men, an option to preserve fertility is to freeze their sperm.

Women who wish to safeguard their future ability to have children can opt to freeze their eggs. The technical term for this is oocyte cryopreservation. The process was developed in the 1980s, with the first birth from a frozen oocyte taking place in Australia in 1986. In the decades since, the techniques have been refined.

Today, oocyte cryopreservation has moved from an experimental procedure to an accepted treatment. It is so widely used that some large employers cover the procedure in their employee health insurance plans.

If your sister chooses to move forward with freezing her eggs, she will begin by seeking out the professionals who will help her. That means an experienced fertility specialist and a reputable reproductive clinic, preferably with an on-site lab. The medical team overseeing her cancer care may be able to offer recommendations.

The actual process begins with one or more prep appointments. These typically include an office meeting to explain the procedure, answer questions and fill out paperwork related to the process. Patients also undergo a blood draw to determine certain hormone levels and have a transvaginal ultrasound to allow the doctor to visualize the ovaries. In order for the ovaries to release multiple eggs, patients are prescribed synthetic hormones with which to inject themselves. This is known as ovarian stimulation, and it takes place on a precise schedule.

Over the next few weeks, patients return to the clinic for further blood tests and ultrasounds. These are used to track the body's response to the injections. When the eggs are ready to be retrieved, the patient receives an injection of a medication that helps the eggs mature. Retrieval takes place at the clinic, with the patient under sedation. Guided by ultrasound imaging, the doctor uses a needle to pierce the sac that contains the egg. A suction device helps to gently remove it. The harvested eggs are then cooled to a subzero temperature and placed in a specialized storage facility, where they are preserved until needed.

The process of oocyte cryopreservation can help preserve fertility, but your sister will be advised that it isn't foolproof. It can also be costly. When not covered by insurance, egg freezing can range from about $10,000 to more than $20,000 per cycle. Multiple cycles can be needed in order to collect enough eggs. Additional costs include an annual fee to store the eggs and the fee for in vitro fertilization when it comes time to use them.

Q: I went to our local pharmacy to get a flu shot for myself and also for my dad. It turns out that because he is 68 years old, he didn't get the same vaccine as me. They gave him something called "fluad quadrivalent." How is that different from the regular flu vaccine? Why did he need it?

A: First, we want to thank you for taking an important step in safeguarding your health and that of your father. Flu season in the United States started early this winter, and it is turning out to be particularly severe. It has resulted not only in widespread illness, but also in high rates of hospitalization. That makes getting vaccinated particularly important.

Due to age-related changes to the immune system, older adults are at increased risk of developing potentially life-threatening complications from a case of the flu. According to data collected by the Centers for Disease Control and Prevention in recent years, well over half of hospitalizations due to the flu, and up to 85% of flu-related deaths, have occurred in adults 65 and older. People of all ages who are living with underlying conditions such as diabetes, asthma, lung disease and heart disease are also at increased risk.

The good news is this year's flu vaccine is proving to be effective at reducing the severity of disease and decreasing the risk of hospitalization. By getting vaccinated, you and your dad are protecting yourselves, as well as the people around you.

To understand the difference between the shots you and your father received, we should first define a few terms. All flu vaccines contain something called an antigen. That's a molecular structure found on the surface of viruses, including the influenza virus. When a virus infects the body, the antigens it contains act as an alarm bell. Their presence triggers the immune system to produce specialized proteins known as antibodies, which attack the invaders.

Flu vaccines work by teaching your immune system to recognize specific antigens. This primes the immune system to be ready with a strong protective response. Although your father got a different shot than the one you received, he did not get a different vaccine. Rather, he was given what is known as a high-dose flu vaccine. That's a shot that contains the same antigens as the regular flu vaccine but is specially formulated to elicit a stronger immune response.

At this time, several types of high-dose flu vaccines are approved for use in the U.S. Each one is formulated in a slightly different way, but all have the same effect - that is, to rev up immune response.

The fluad quadrivalent shot your father received contains something called an adjuvant. That's an added compound that causes a markedly stronger immune response. Another high-dose flu shot, known as Fluzone High-Dose quadrivalent, achieves the same result by upping the quantity of antigens contained in the vaccine.

As with all flu shots, side effects can include soreness or swelling at the site of the injection, fever, muscle aches, headache or nausea. To locate a high-dose flu shot near you, visit vaccines.gov/find-vaccines.

• Dr. Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr. Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health. Send your questions to askthedoctors@mednet.ucla.edu.