Top things to know about IVF
In vitro fertilization (IVF) is a method of assisted reproduction in which eggs are combined with sperm and fertilized outside the body in a laboratory.
It is most commonly performed as a treatment for infertility.
IVF can increase the chances of conceiving and live birth, but the success rates will depend on individual factors.
Trying to conceive can be a different experience for different people. While many couples will conceive in the first few months, for others, it can often take longer—even up to a year (1). Some may experience difficulty becoming pregnant or will be diagnosed with infertility. Luckily, there are different treatment options available that can increase the odds of conceiving.
This article will explain one of the more widely known types of assisted reproductive technologies (ART); how it works, why it’s done, the risks, and the success rates. If you are wondering if you should see a fertility specialist, we have written this guide for you.
So, what is in vitro fertilization (IVF)?
In vitro fertilization (IVF) is a medical procedure in which eggs (oocytes) are surgically removed from the ovaries and combined with sperm in a Petri dish to fertilize them (“in vitro” is Latin for “in glass”) (2,3). The fertilized eggs are incubated for several days to grow to the embryo stage and then placed into the uterus for the individual to try and become pregnant (2).
Why is IVF performed?
Your fertility doctor may suggest less invasive treatment options before trying IVF, depending on your specific situation. This includes taking medications to increase the production of eggs (ovulation induction) and/or intrauterine insemination (IUI)—a procedure in which washed sperm are placed directly inside the uterus around the time of ovulation (4). But when these treatments aren’t successful, or in cases where there is damage to the fallopian tubes, a medical or genetic condition, or issues with egg or sperm health, IVF may be the best option for conceiving (4-6).
You may consider IVF if you or your partner has any of the following conditions:
Polycystic ovary syndrome (PCOS): PCOS can cause hormonal disturbances that can affect ovulation and conception (7). If there are no other factors affecting fertility, ovulation induction therapy is typically the first and second line of treatment before moving on to IVF (7).
Endometriosis: Endometriosis is a common condition where tissue similar to the uterine lining grows in other areas outside the uterus (8). Endometriosis can affect the function of the ovaries, fallopian tubes, and uterus, making it more difficult to conceive (8). IVF may be recommended in moderate to severe endometriosis cases (4,9).
Blocked or damaged fallopian tubes: The fallopian tube is where fertilization (sperm meeting egg) happens. Blocked or damaged fallopian tubes can make it difficult for an egg to be fertilized or for an embryo to travel to the uterus (5). A history of pelvic inflammatory disease and previous tubal surgery are common causes of tubal damage and account for 25–35% of all female-factor infertility (5)
Previous tubal ligation or removal: Having your “tubes tied” permanently prevents pregnancy by blocking or removing the fallopian tube (5). To conceive after tubal ligation or removal, IVF may be an alternative to tubal ligation reversal surgery (5).
Issues with sperm production or sperm quality: Atypical structure or function of sperm such as altered motility (the ability for sperm to swim towards the egg), atypical shape, DNA or protein changes, and a lower sperm count are all factors that impact the ability to conceive (10,11). Sperm health may be the sole underlying factor in up to 20% of infertile couples and a contributing factor in another 30–40% (12).
Primary ovarian insufficiency (POI): Primary ovarian insufficiency is the medical term for when the ovaries have fewer functioning follicles (fluid-filled sacs that contain eggs) than is typical in someone under 40 years old. Individuals with POI who are unable to produce their own eggs may consider IVF with donor eggs (13).
Risk of passing on a genetic disorder: IVF allows for the opportunity to perform preimplantation genetic testing to screen embryos for specific genetic conditions that can be inherited from one or both partners (6). Embryos that don’t carry the genetic disorder can be transferred to the uterus (6). Not all genetic conditions can be tested for, however (6).
Unexplained infertility: Unexplained infertility is diagnosed when there is no apparent cause for infertility found after testing for the common causes. For couples experiencing conception challenges, up to 30% are diagnosed with unexplained infertility (14).
Using donor eggs or a surrogate: IVF with donor eggs is an option for individuals who can’t use their own eggs for various reasons (15). Intended parents who do not have a functional uterus or for whom pregnancy poses a health risk may choose to use a gestational carrier or surrogate (a person who did not provide the egg used in conception but carries the fetus through pregnancy and birth for the intended parent/s) (15).
What are the steps of the IVF process?
1. Consultation and testing
The first step in the IVF process is to have a consultation with a doctor called a Reproductive Endocrinologist (REI) at a licensed fertility clinic. They will perform a blood test called an anti-Müllerian hormone (AMH) test, along with testing of other hormones, and an ultrasound (sonogram) of your ovaries to determine your ovarian reserve (16). These tests give your doctor an indication of the number of eggs in your ovaries that can be collected for fertilization. Your blood will also be tested for certain infectious diseases, thyroid function, and other markers of your overall health (3,16).
2. Ovarian stimulation
Once you’ve completed all the tests, your doctor will make a plan called a protocol. It’s based on your age, hormones, and any medical condition that you or your partner have experienced or continue to experience (17). You’ll begin by tracking your cycle. In some cases, you may take the oral contraceptive pill or another medication called a gonadotropin-releasing hormone agonist (GnRHa) to prime your ovaries for stimulation (3,18).
When you’re ready to begin stimulation, you’ll be taught how to give yourself injections of gonadotropin hormones such as follicular stimulating hormone (FSH) and luteinizing hormone (LH). These injections will stimulate your ovaries to produce more follicles (3). Some people may choose to enlist the help of a partner, family member, or friend. It’s also possible to do IVF without ovarian stimulation, in what’s called a natural cycle IVF—but this method is less common (3).
During ovarian stimulation, you’ll have frequent blood tests to monitor your hormone levels and ultrasounds to watch how the follicles grow and how your uterine lining thickens (17). The ovarian stimulation part of your IVF cycle can take between eight and 12 days (19).
Once your follicles have reached a certain size and your hormones are at a certain level, you’ll be instructed to give yourself an injection of human chorionic gonadotropin (hCG) at home (20). This injection is sometimes called a trigger shot and is designed to help the eggs mature. Depending on your protocol, you may receive a GnRHa trigger instead (20).
3. Egg retrieval and sperm collection
Approximately 36 hours after the trigger shot, you’ll be ready for egg retrieval (21). The procedure typically takes place at your fertility clinic while you are asleep under anesthesia or sedation and typically takes around 30 minutes (22). The most common way to retrieve the eggs is through vaginal ultrasound aspiration, in which an ultrasound probe is inserted into your vagina to locate the follicles (21).
A needle is then guided through the vaginal wall and into a follicle (21). A suction device connected to the needle is used to remove the egg from the follicle (21). The number of eggs that can be collected from one ovarian stimulation cycle will depend on your age, ovarian reserve, the cause of infertility, and how you respond to the hormones (23).
After your egg retrieval, you may experience mild to moderate pelvic and abdominal pain (24). These sensations usually go away in a day or two and can be managed with over-the-counter pain medications (24). After the procedure, you may still feel groggy from the anesthesia or sedation, so you’ll need someone else to drive you home.
On the same day of the egg retrieval, your partner may provide a sperm sample in the clinic (or bring one from home), or the clinic will thaw your partner’s previously frozen sperm or the frozen sperm of a donor (25).
4. Fertilization and embryo development
Shortly after egg retrieval and sperm collection, the eggs will be combined with sperm in a Petri dish to allow fertilization. In some cases, an embryologist (a scientist that works with embryos) will carefully select one sperm and inject it directly into the egg (2). This method of fertilization is called intracytoplasmic sperm injection (ICSI) and is most commonly done when there is an issue with sperm quality or a history of prior unsuccessful IVF attempts (26).
Over the next three to five days, an embryologist will monitor the fertilized eggs as they develop into embryos (3). By day five, the embryos will have reached the blastocyst stage, and this is when the embryo transfer typically happens, though in some cases, the embryo transfer may happen earlier (3,27). Extra embryos that are not transferred can be frozen for future use (27). Typically, not all eggs will fertilize, and not all fertilized eggs will develop into blastocysts (23,27).
Soon after fertilization, your doctor will likely prescribe supplemental progesterone as an injection, vaginal suppository, or vaginal gel (28). This hormone will help to prepare your uterine lining in anticipation of embryo transfer and implantation (28). This medication is typically continued until a positive pregnancy test and up to 12 weeks of pregnancy, but your doctor will advise you on this (28).
5. Testing the embryos
If preimplantation genetic testing (PGT) is planned, the embryos will be biopsied (a few cells are removed from the embryo and genetically tested) (6). PGT can test for aneuploidy (if the embryo contains the wrong number of chromosomes) or for a specific known genetic condition (6). Not all genetic conditions can be tested for (6). Embryos that are tested are typically frozen until the results are available. If the embryo contains the right number of chromosomes (euploidy) or does not carry the specific genetic condition, then it may be transferred into the uterus (6).
6. Embryo transfer
The embryo transfer typically takes place three to five days after egg retrieval, or if you are using frozen embryos (a frozen embryo transfer or FET), whenever your uterine lining is ready for implantation (2). The number of embryos transferred will depend on your age, embryo stage, embryo quality, and personal preference (3). The embryo transfer doesn’t require any anesthesia or sedation, so you’ll be awake for the procedure (29). Guided by ultrasound, the doctor will place a thin catheter through the cervix and into the uterus. A syringe containing the embryo(s) is attached, and the doctor will push the plunger to complete the transfer into the uterus (29). Other than possible mild discomfort, the procedure is typically pain-free, and you can return home immediately after (24,30).
7. Pregnancy test
About two weeks after the embryo transfer, you’ll have a blood test to confirm that the embryo implanted into the uterus and created a pregnancy. In some cases, you may be advised to take a home pregnancy test and let your clinic know the result. It’s important not to take a home pregnancy test before your clinic advises, as testing too early can give you a false-positive result (if your trigger shot contained hCG) or a false-negative (if it’s too soon for the pregnancy to produce enough hCG) (31).
What are the risks associated with IVF?
IVF is a common procedure that is considered a minor surgery. Serious complications associated with the medications and egg-retrieval process are rare (24). However, like all medical procedures, things can happen unexpectedly.
The risks include:
Ovarian hyperstimulation syndrome (OHSS): OHSS is a complication of ovarian stimulation (32). Most symptoms of OHSS (nausea, bloating, and ovarian discomfort) are mild and treated with over-the-counter pain medication (32). In very rare cases, severe OHSS can be life-threatening (32). It’s important to contact your fertility clinic if you have:
Continued vomiting or nausea
Difficulty tolerating fluids
Sudden onset of abdominal pain
Complications from the egg retrieval procedure: Your healthcare provider will give you specific instructions, but some potential issues could be bleeding, infection, and thrombosis (blood clots blocking veins or arteries) (24). Being put to sleep, or under anesthesia can also come with some unexpected events. Your anesthesiology provider can tell you about these.
Multiple pregnancy (pregnancy with more than one fetus): Guidelines for fertility treatment aim to maximize the chances of pregnancy while minimizing the chances of a multiple pregnancy (33). Transferring multiple embryos increases the live birth rate per transfer but also increases the risk of a multiple pregnancy (33). Pregnancy with more than one fetus increases the likelihood of serious, even life-threatening complications for both the birthing parent and the infant (33). The best way to limit the risk of a multiple pregnancy is to transfer a single embryo (33).
Emotional implications: A diagnosis of infertility can bring up many difficult emotions, including sadness, shame, guilt, anger, and loss of control (34). The use of IVF can be physically, emotionally, and financially draining (35). IVF is sometimes considered the “last chance” at biological parenthood, but there is no guarantee the procedure will be successful or result in a live birth (35). Practicing self-care and seeking out support from friends and family, and fertility counselors can help you cope with the uncertainties of treatment (35).
What are my chances of a live birth with IVF?
Fertility clinics and organizations like the Society for Assisted Reproductive Technology (SART) report data on the outcomes of IVF cycles carried out each calendar year (36). While this data can give you an idea of the average chances of success per IVF cycle and embryo transfer, it’s important not to let these numbers guide your medical decisions. These statistics may not apply to an individual person or couple because the success rates of IVF will vary greatly based on individual factors and treatment characteristics (37).
These individual factors include:
Maternal age: The younger you are, the more likely IVF will result in a live birth when using your own eggs (37, 39).
Embryo quality and quantity: A higher number of good-quality embryos available for transfer is associated with a higher live birth rate (38,39).
Cause of infertility: Some causes of infertility may have a better IVF outcome than others, but this varies by study (38, 39). For example, IVF treatment for PCOS-related infertility may have a better live birth outcome than other causes of infertility (39).
Reproductive history: If you’ve previously given birth, you may be more likely to have a live birth with IVF than someone who has never given birth (38, 39). Success rates are lower for individuals who have previously used IVF but did not become pregnant (38, 39).
While this article aims to give you an overview of IVF and what to expect, it’s important to speak to your healthcare provider about your specific case and any factors that may affect your treatment.