IVF is used by many different people and families. This includes:

• Couples who have trouble conceiving on their own
• Same-sex couples
• People who decide to become single parents
• Individuals who use donor eggs or who are working with a gestational carrier

Learning how IVF works and what the process involves can help make treatment feel more approachable and less overwhelming.                         

“During IVF treatment, there is a careful balance of advanced science and compassionate care to help support individuals and families through every step of their journey,” says MaryEllen G. Pavone, MD, a reproductive endocrinologist and infertility specialist at Northwestern Medicine and IVF medical director at Northwestern Medicine Center for Fertility and Reproductive Medicine.

What Is IVF and How Does It Work?

IVF is a medical process in which eggs and sperm are combined outside of the body to create embryos. If fertilization occurs, usually one embryo is transferred into the uterus to help establish a pregnancy.

An embryo transfer can occur during the same cycle as the eggs are retrieved (fresh transfer) or at a later time if using frozen embryos (frozen transfer). 

An IVF cycle usually takes about two to five weeks from start to finish. While the process involves several steps, many people find it manageable with support from their care team.

Here’s a step‑by‑step look at how the IVF process works:

1. Ovarian stimulation

The process begins with fertility medications that stimulate the ovaries. These medications help the ovaries grow multiple eggs during a single cycle, rather than the single egg typically released each month.

2. Monitoring and blood tests

Throughout stimulation, regular ultrasounds and blood tests are used to check how the eggs are developing and track hormone levels. This monitoring helps physicians adjust medications and choose the best timing for the next step.

3. Egg retrieval

When the eggs are ready, they are collected during a short outpatient procedure called an egg retrieval. It is done under sedation, and most people go home the same day and recover quickly.

4. Fertilization

In the lab, eggs are placed in a Petri dish and combined with sperm so the fertilization of eggs can occur. In some cases, intracytoplasmic sperm injection (ICSI) is used, where a single sperm is injected directly into each egg to support fertilization.

5. Embryo development

Once fertilized, the eggs develop into embryos over several days while your care team carefully monitors their growth.

6. Embryo transfer

Usually one embryo is transferred into the uterus during a simple procedure that does not require anesthesia. This may occur during a fresh or frozen embryo transfer.

Unused embryos that develop successfully may be frozen for possible use in the future.

Although IVF requires time and planning, most people can continue with their usual daily routines during treatment. Your care team will help you understand what to expect and how to manage the schedule.

Risks and Side Effects of IVF

IVF is widely used and considered safe, but like any medical treatment, it can come with side effects. Most are temporary and manageable.

Common side effects include:

• Bloating, abdominal discomfort, weight gain and changes in mood during ovarian stimulation
• Bruising or soreness at injection sites
• Temporary cramping, fatigue or discomfort after egg retrieval

Less common but more serious risks include:

• Multiple pregnancy if more than one embryo is transferred (In most cases, a single embryo is transferred.)
• Ovarian hyperstimulation syndrome (OHSS), a reaction to fertility medications that is carefully monitored and treated if it occurs
• Bleeding following an egg retrieval, which is rare and may require hospitalization or a possible blood transfusion
• Ovarian torsion, where the ovary twists on its blood supply and requires immediate surgery

“Fertility care teams closely monitor each step of treatment and follow evidence‑based standards, including guidance from the practice committee of the American Society for Reproductive Medicine (ASRM),” says Dr. Pavone. “This careful monitoring helps reduce risks and support safety throughout the IVF process.”

Who Is IVF Recommended For?

IVF is often recommended when other fertility treatments, such as medications or intrauterine insemination (IUI), haven’t led to pregnancy. For some people, IVF may also be suggested as a first option based on medical history or timing.

IVF may be recommended for individuals who have:

• Blocked or damaged fallopian tubes
• Severe male‑factor infertility
• Endometriosis
• Age‑related fertility decline
• A history of miscarriages
• A higher risk of having a genetic disorder

In some cases, embryos may be genetically tested before transfer, which can guide decision‑making and family‑planning options.

A fertility specialist can help explain when IVF may offer the best chance of pregnancy based on your circumstances.

What Are the Success Rates for IVF?

Successful IVF pregnancy rates vary from person to person and depend on several factors. These include:

• Age of the person providing the eggs
• Egg and sperm quality
• Overall health and lifestyle factors
• Number of embryo transfer attempts
• Whether embryos are genetically tested

“In general, IVF offers a higher success rate than many other fertility treatments,” says Dr. Pavone.

IVF Success Rates by Age

According to the preliminary national summary report for 2024 from the Society for Assisted Reproductive Technology (SART), IVF success rates vary significantly by age when using a patient’s own eggs for a single birth.

For women* under age 35, live birth per egg retrieval is about 40%. This number includes one retrieval and all embryo transfers resulting from that one retrieval.

For women age 35 to 37, the live birth rate per egg retrieval is about 29%, and for women age 38 to 40, it is about 18%.            

Fertility clinics track and report success‑rate data to show how often IVF results in pregnancy or live birth under different conditions. A fertility specialist can help interpret these numbers and explain what they may mean for your specific situation rather than relying on averages alone.

IVF Compared With Other Fertility Treatments

Many people try IUI before IVF. With IUI, sperm is placed directly into the uterus, and fertilization happens naturally inside the body.

“IVF offers more oversight. Fertilization takes place in a laboratory, which allows specialists to closely monitor embryo development and, in cases where there are multiple embryos, select the best embryo for transfer,” says Dr. Pavone. “This can be helpful when fertility challenges are more complex.”

Because of these differences, IVF generally has a higher success rate than IUI. A fertility specialist can help explain when IVF may offer better chances based on your circumstances.

“Your fertility doctor will talk to you about your options and fertility goals and together you will come up with a treatment plan,” says Dr. Pavone.

The Role of Lifestyle in IVF Success

Lifestyle habits play an important role in how the body responds to IVF. There are several factors that can affect hormone balance and overall health, which may influence treatment outcomes.

Habits that support an overall healthy lifestyle include:

• Eating a balanced, nutrient‑rich diet
• Maintaining a healthy body mass index (BMI)
• Getting consistent quality sleep
• Staying active with regular movement before starting an IVF cycle
• Managing stress through mindfulness, relaxation techniques or counseling
• Avoiding tobacco and alcohol

These changes don’t need to be perfect to be helpful. Even small, consistent adjustments can support your body before starting fertility treatments and may help you feel better physically and emotionally throughout treatment.

What Experts Wish People Knew About IVF

It’s common to assume that IVF guarantees pregnancy. While IVF is one of the most effective fertility treatments available, it doesn’t promise success every time. Understanding this early can help set realistic expectations and reduce added pressure during treatment.

“IVF works best when care is personalized. Factors like maternal age, diagnosis and overall health all play a role, which is why treatment plans are tailored to each individual or couple,” says Dr. Pavone.

Support from friends and family members along the way can make a meaningful difference. A care team that communicates clearly, listens and tailors treatment to your needs can also help you feel supported throughout the IVF experience.

* Scientists do not always collect information from participants about gender identity. To avoid misrepresenting the results of this research, we use the same terminology as the study authors.