Yet this incredible breakthrough is also a complex medical process, and one that comes with risks, side effects, and limitations that aren’t always understood. We’ve dug deep into the latest research on egg freezing to bring you everything you need to know.

Egg freezing, medically known as oocyte cryopreservation, is a procedure in which a person’s eggs are retrieved from their ovaries, rapidly frozen, and stored in liquid nitrogen tanks at subzero temperatures. Later, if the person wishes to have children, those eggs can be thawed, fertilized with sperm, and implanted through in vitro fertilization (IVF).

It’s important not to confuse egg freezing with embryo freezing, a process in which eggs are fertilized before being frozen. Embryo freezing has been used successfully for longer, although in recent years, egg freezing success rates have approached those of embryo freezing.

Egg freezing is, naturally, the preferred option for people who don’t know who they might want to fertilize their eggs with or who prefer to preserve their reproductive material without committing to a partner or donor.

The primary motivation for egg freezing is timing. Eggs decline in both number and quality with age, especially after thirty-five. By freezing eggs earlier, people can preserve them at a younger biological age.

The procedure isn’t new. The first successful live births from frozen eggs happened in 1986, when a pair of twins were born thanks to early cryopreservation techniques. At the time, however, egg freezing was unreliable. The problem was ice. Freezing eggs slowly often causes ice crystals to form inside the cells, damaging them and reducing the chances of survival.

That changed with the development of vitrification, a rapid freezing method in which eggs are cooled so quickly that water molecules don’t have time to form crystals but instead enter a glass-like state. Add to that the improvements in lab culture conditions, IVF techniques, and hormone treatments, and egg freezing went from being a risky experiment to a mainstream option. In 2012, the American Society for Reproductive Medicine announced that the procedure should no longer be considered experimental. Since then, its use has expanded considerably.

Everyone’s fertility journey is different, and so are the reasons for freezing eggs. Yet motivations tend to fall into a few categories.

For many, it’s about delaying parenthood. Women or people with ovaries may want more time to travel the world, build their own business, earn another master’s degree, or learn the trickiest move in pole dancing: the Rainbow Marchenko. Starting a family before their fertility begins to decline isn’t always what they want. Egg freezing gives people more time.

Others undergo egg freezing for medical reasons. Cancer treatments like chemotherapy and radiation can damage fertility, so patients sometimes freeze eggs beforehand as a protective measure. Similarly, people with endometriosis, autoimmune diseases, or conditions linked to reduced ovarian reserve may use egg freezing as a safeguard.

Then there is the hard fact, to quote Diana Ross, that “you can’t hurry love.” Some people want children one day but haven’t yet met a partner with whom they’d like to have them. Freezing eggs makes swiping on apps and going on first dates a little less stressful, giving people more breathing room in their timeline.

Egg freezing is also an option for transgender individuals. For trans men planning to undergo hormone therapy or surgery that could impact fertility, preserving eggs beforehand offers a chance at biological children in the future.

The egg freezing cycle involves several different stages. You can expect each cycle to take two to six weeks.

Step One: Consultation and Testing

The process begins with a consultation and fertility evaluation. Doctors use blood tests and ultrasounds to assess ovarian reserve and reproductive health.

Two key hormone tests are commonly used: Anti-Müllerian Hormone, which indicates the number of eggs remaining in the ovaries, and Follicle Stimulating Hormone, which shows how well the ovaries are functioning. An antral follicle count via ultrasound also helps estimate the number of eggs that could potentially be retrieved.

Other tests may include genetic screening or a transvaginal ultrasound to check for ovarian cysts or fibroids. Doctors then review your medical history, such as previous pregnancies, miscarriages, or illnesses, and discuss your fertility goals.

The amount of time between this initial consultation and the next step will depend on where you are in your menstrual cycle.

Step Two: Ovarian Stimulation

In a normal menstrual cycle, only one egg matures. During egg freezing, the goal is to retrieve as many mature eggs as possible in a single cycle. To achieve this, patients self-administer daily hormone injections over ten to fourteen days that stimulate the ovaries, leading to the maturation of more eggs.

The medications used include gonadotropins, which stimulate the ovaries to produce multiple eggs, and gonadotropin-releasing hormone agonists, which prevent premature ovulation. Once the eggs are nearly mature, an injection of human chorionic gonadotropin triggers final maturation and loosens the eggs for retrieval. Throughout this stage, patients visit the clinic every few days for ultrasounds and blood tests to monitor progress.

While the idea of daily injections can feel daunting, most patients report that it becomes routine, though the hormonal changes can cause bloating, mood swings, and fatigue.

Step Three: Egg Retrieval

When the eggs are ready, they are collected in a short outpatient procedure under sedation. Using ultrasound guidance, a doctor inserts a thin needle through the vaginal wall to aspirate the eggs from the ovarian follicles. The process takes about fifteen to thirty minutes, and while mild discomfort or cramping is common afterward, recovery is usually quick.

Step Four: Freezing and Storage

The collected eggs are immediately evaluated for maturity and frozen through vitrification. They are then stored in liquid nitrogen at –196°C, where they can remain indefinitely. Research suggests that long-term storage does not harm eggs, though most data is based on storage periods of fewer than ten years.

Some labs may have a maximum age at which you can use your eggs, since the risks of pregnancy increase with age, so make sure you are fully aware of the conditions before choosing a clinic.

When a person decides to use the eggs, they undergo a thawing process called oocyte warming. The eggs are then fertilized, usually via intracytoplasmic sperm injection, a form of IVF in which a single sperm is injected directly into each egg. If fertilization is successful, embryos are cultured for several days before being transferred into the uterus.

Egg freezing is considered safe, but like any medical procedure, it carries risks. The most common complication is ovarian hyperstimulation syndrome (OHSS), in which the ovaries over-respond to fertility drugs, becoming swollen and painful. Most cases are mild, causing bloating and discomfort, but in rare cases, OHSS can lead to serious complications like fluid buildup and blood clots.

The egg retrieval procedure also carries small risks of infection, bleeding, or injury, though these are uncommon. The hormonal medications can cause side effects such as mood swings, headaches, or fatigue, and the overall process can be emotionally draining.

Long-term health risks appear minimal, but research is ongoing. For most patients, the psychological uncertainty—the not knowing whether the investment of time, money, and physical effort will eventually result in a child—is one of the hardest parts. Going through egg freezing and IVF can take a serious toll on mental health.

It is also important to note that egg freezing does not guarantee a successful pregnancy. On average, about 90 percent of vitrified eggs survive thawing, and 70–80 percent of those can be successfully fertilized. The likelihood of achieving a live birth depends heavily on the age at which the eggs were frozen. One 2022 study found that women who froze twenty eggs at age thirty-five had about a 70 percent chance of having at least one child. By contrast, eggs frozen at forty or older are significantly less likely to result in a live birth, even with higher numbers.

If your partner or a loved one is going through egg freezing, they may need your support. The first way to provide this is to educate yourself on the procedure and the steps they will be going through.

The second, and most important thing, is to let them be your guide. For some people, it might be a massive emotional upheaval. Some might suffer severe side effects from the hormones. Others might approach the procedure casually and need you not to make a big deal out of it. Listen to what they are experiencing, and ask them what they need from you. Cut them some slack if they are more irritable than usual. Be patient and kind.

Lastly, know that you should never pressure someone to undergo egg freezing. You might be anxious about your partner’s fertility, and what it means for your possibility of having children with that person. But fundamentally, the choice to go through egg freezing can only be made by the person with the eggs. All you can do is love and support them.