IVF Procedures

In vitro fertilization (IVF) is an assisted reproductive technique where eggs are combined with sperm outside the body, then the resulting embryo or embryos are transferred into a uterus (called an embryo transfer). The process is performed at a fertility clinic and can help couples conceive if they are having trouble doing so, often after completing other, less invasive fertility interventions. IVF can also be an option for individuals without fertility issues, including single females, same-sex couples, and people with certain medical conditions such as cancer.

IVF can be performed using a female’s own eggs and her partner’s sperm, or with donor eggs or donor sperm. Embryos from IVF, whether donor embryos or embryos created from a female’s own eggs and partner’s sperm, may be transferred to either the intended parent’s uterus or into the uterus of a gestational carrier (colloquially referred to as a “surrogate”). Sometimes the term “IVF” is used to refer to the process of freezing eggs (oocyte cryopreservation) even if fertilization and creation of embryos does not take place.

For patients going through in vitro fertilization (IVF) or any type of fertility treatment, the clinic will build a comprehensive plan to examine all risk factors, health conditions, and reproductive issues that may interfere with the patients’ ability to conceive. Much of this plan will be related to the form and function of the female reproductive system, and the uterine lining (also called the endometrium or endometrial lining) is one part of the reproductive system that will be assessed.

The endometrial lining changes in thickness and appearance in response to the changing hormone levels throughout the menstrual cycle; therefore, it is part of the assessment for how a patient is responding to fertility treatment.

Egg donation is a process by which a fertile female donates her eggs (oocytes) to another individual or couple who want to conceive a baby. There are several steps involved in the decision to use donor eggs, and many more things to consider once the choice has been made. For anyone thinking about using donor eggs, it is important to understand the details around how egg donation works and how to find an egg donor. Being aware of egg donation success rates is also key.

Sperm retrieval procedures are used to remove sperm from the testicles for the purpose of fertilizing an oocyte (egg). They may be used for males who have zero sperm count in their ejaculate (azoospermia) but still produce sperm in the testes.

There are two main techniques for surgical sperm retrieval: aspiration and extraction. Sperm aspiration involves using a needle to aspirate (remove) sperm from the epididymis or the testes. Testicular sperm extraction takes a sample of the tissue, known as a biopsy, to collect the sperm. There are also different variations or subtypes of these procedures, as well as non-surgical approaches for individuals with ejaculation limitations.

Preimplantation genetic testing (PGT) is the general term for genetic testing performed on human embryos used for in vitro fertilization (IVF) and before transfer to the uterus. PGT aims to improve the chances of a successful ongoing pregnancy after embryo transfer.

While genetic testing does not impact or change the genetics of an embryo, it gives doctors and prospective parents more information and may help them select the most viable embryo(s) for transfer. It is important to understand that PGT will not improve the cumulative live birth rate of a given IVF cycle and that there are both advantages and disadvantages to PGT.

As part of a reproductive treatment plan to assist in becoming pregnant, a physician may recommend medication to induce ovulation or to accompany timed intercourse, intrauterine insemination (IUI), therapeutic donor insemination (TDI), or in vitro fertilization (IVF). During treatment, a reproductive endocrinologist (RE) will most likely prescribe ovarian stimulation to maximize the number of eggs produced.

With regard to in vitro fertilization (IVF), potential success is highly dependent on being able to retrieve enough high-quality eggs that may subsequently go on to produce healthy embryos. Part of that process involves ovarian stimulation. In some cases, fertility doctors will suggest priming protocols. As patients seeking pregnancy review the various IVF protocols suggested, it is important to understand what priming protocol may be best for them. This includes knowing how these protocols can impact reproductive health, what the protocols are used for, what drugs will be required, and what the success rates are.

Preimplantation genetic testing (PGT) is the general term for genetic testing that is performed on embryos produced by in vitro fertilization (IVF) before the embryos are transferred to the uterus. The purpose of PGT is to improve the chances of having a successful embryo transfer. Genetic testing does not impact or change the genetics of an embryo, but it does give doctors and prospective parents more information and may help them select the most viable embryos for transfer.

There are three types of PGT: PGT for monogenic disorders (PGT-M), PGT for structural chromosomal rearrangements (PGT-SR), and PGT for aneuploidy (PGT-A). PGT-A is the most routine type performed. As such, it is an important area of education for prospective parents.

Menopause is a natural process all females will eventually go through as they reach middle age. During menopause, the ovaries stop releasing eggs, menstrual periods become less frequent and eventually cease, and hormones such as estrogen and progesterone decrease. While menopause marks the end of fertility, there is still a chance to get pregnant during menopause — either naturally or through fertility treatments.

Mitochondrial replacement therapy (MRT) is a highly controversial procedure used to either prevent genetic disease or support in vitro fertilization (IVF) success when advanced maternal age may be an issue. The therapy is not currently practiced or legal in many countries, including in the United States or Canada, as it is considered a very experimental form of genetic modification.

Mitochondrial replacement therapy often comes up when the term “three-person baby” is searched online, even though the two concepts are not synonymous. Several terms are frequently misused in attempting to define mitochondrial replacement, and the procedure itself is often misunderstood.

To increase the chances of a successful pregnancy, embryo grading is completed by an embryologist during an in vitro fertilization (IVF) cycle. Assessing embryos for quality at specific stages of embryo development can be a valuable tool in reproductive medicine to help the doctor decide which embryo to transfer first (when there is more than one embryo available for transfer).

At times, difficulty with conception can be traced to issues within the structure of the reproductive tract, such as the shape of the uterus or blockages in the fallopian tubes. If a physician suspects structural concerns, they may recommend a hysterosalpingogram. The hysterosalpingogram is a relatively common diagnostic procedure in reproductive medicine that gives doctors the ability to see how the uterus and fallopian tubes are shaped.

After an egg retrieval for a fresh cycle, or when contemplating a frozen embryo transfer, patients often wonder how many embryos should be placed into the uterus. Usually, single embryo transfer (SET) is promoted, especially if an embryo is genetically tested, meaning it undergoes preimplantation genetic testing (PGT). However, there are cases where a patient may want to transfer two or more embryos. Examining the pros and cons of multiple embryo transfers can help patients make an informed decision.

An embryo transfer is usually the final step in the process of in vitro fertilization (IVF), in which the embryo is transferred to the patient’s uterus. The embryos used in this procedure may either be fresh or thawed (after being frozen).

During IVF, mature eggs are fertilized, either by conventional IVF (insemination) or intracytoplasmic sperm injection (ICSI). Next, the resulting embryos are grown in an incubator in the embryology laboratory. Finally, an embryo transfer is the procedure whereby one or more of the embryos that have been grown in the lab are then transferred into the patient’s uterus in the hopes of initiating a pregnancy.

Fresh embryo transfers involve transfer to the uterus several days after egg retrieval within the same IVF cycle. The embryo is never frozen.ⁱ Alternatively, embryos can be frozen and preserved (known as cryopreservation), then stored to be transferred in a subsequent cycle. This process is known as a frozen embryo transfer (FET) and requires the cryopreserved embryo to be thawed before transfer into the uterus.ⁱⁱ

Donor eggs (oocytes) are derived from an individual other than the intended parent(s). This involves in vitro fertilization (IVF), where the recipient uses healthy and fertile donor eggs to conceive. Recipients of donor eggs are often uncertain as to whether they should choose to use fresh or frozen donor eggs, and the differences between the options.  This article explores the pros and cons of using fresh vs. frozen donor eggs.

Individuals who are transgender or transitioning face unique issues regarding fertility, family building, and fertility preservation. Still, transgender parenthood is fairly common. Of the respondents to the U.S. Transgender Population Health Survey, 19 percent of trans individuals were parents.ⁱ Below, learn about options for creating a family as a transgender person, fertility considerations for individuals undergoing gender transition, as well as pregnancy, the delivery process, and aspects of postpartum life for trans individuals.

Note: Some transgender individuals prefer to be identified only as men/male or women/female, dropping the term transgender. Others prefer the terms trans man or trans woman. This article will use trans or transgender terminology for clarity, while recognizing the differences in preferred language.

Conceiving through in vitro fertilization (IVF), or other assisted reproductive technology, is a multifaceted process that involves several steps. Once eggs have been retrieved, successfully fertilized, and the embryos have developed, the embryo transfer procedure is planned by the reproductive endocrinologist (REI, also called RE).

IVF embryo transfer processes vary depending on multiple factors, including whether fresh or frozen embryos are used and how many embryos are planned for transfer. Successful embryo implantation into the uterine cavity requires careful planning before the transfer procedure itself. It may also involve lifestyle adjustments for the female during the weeks immediately following the procedure.

Sperm donation is a process in which a fertile male donates semen (ejaculatory fluid containing sperm) that can be used by an individual or couple wanting to have a baby. An understanding of how sperm donation works, what its success rates are, and why people might opt to use sperm donation, are helpful in determining how that fertility journey might look.

Embryo freezing, also known as cryopreservation, is an assisted reproductive technology (ART) that involves storing preimplantation-stage embryos that were created through in vitro fertilization (IVF). The fast-freeze process, known as vitrification, is done at an extremely low temperature (-196°C or -321°F) to halt embryo development and preserve cellular vitality. Following vitrification, these embryos can be safely cryopreserved for extended periods until they are thawed for transfer back to the uterus (called a frozen embryo transfer).

Cryopreservation is necessary when preimplantation genetic testing (PGT) is chosen. Typically, fresh embryos undergo a biopsy before freezing to allow time for the genetic tests to be conducted and results to come back. However, there are cases where patients decide that they want to perform genetic testing of previously frozen embryos. In these circumstances, frozen embryos must be thawed for biopsy, then refrozen until a future date when they might be used. That means the embryos will undergo an additional freeze-thaw round compared to the typical protocol.

Diminished ovarian reserve (DOR) is a condition in which the quantity of oocytes left in a female’s ovaries is low, as determined by ovarian reserve testing. This low number might result in infertility for some individuals. In addition, females with DOR going through fertility treatments are at risk of having a poor response to fertility drugs.

Chromosomes carry DNA, which forms genes that determine multiple aspects of a human’s makeup. A chromosome analysis is often performed to give a healthcare provider more insight into a range of issues, from potential genetic conditions to factors that may be causing recurrent miscarriage.

Embryonic and fetal genetic testing may be recommended for a variety of reasons. Sometimes, individuals or couples have genetic conditions that run in their families. In that case, in vitro fertilization (IVF) with preimplantation genetic testing (PGT) can help select embryos that do not carry the condition. In other cases, patients who have had multiple pregnancy losses may pursue genetic testing of an embryo to help discover a cause. Genetic testing can also give an early glimpse into the sex of the fetus as well as whether the fetus has extra/missing chromosomes that could cause conditions such as Down syndrome or Turner syndrome.

Following an IVF cycle, any resulting embryos that are not transferred to the uterus (fresh transfer) are frozen, or cryopreserved. These frozen embryo(s) will remain frozen until the patient is ready to transfer them (called frozen embryo transfer). However, sometimes there are surplus embryos after the patient has completed their family, or plans change, and embryos remain unused for many reasons. Hundreds of thousands of surplus frozen embryos are currently stored at fertility clinics worldwide – that is, embryos created for fertility treatment and then are not needed by the person(s) that created them.

When a person has frozen embryos in storage that they do not plan to use, it can be difficult to decide what to do with those embryos. When people begin their IVF journey, they may not consider that this is something they may need to think about in the future. Alternatively, if they have considered this, their thoughts on what they plan to do with any unused embryos may have changed. This article outlines the logistical and emotional considerations for the four main options for additional or unused embryos: donation (to medical research, or to another family), destruction, compassionate transfer, and perpetual/indefinite storage.^i,ii,iii

This article will look at broad outlines, practices, and legislation, which do vary depending on where someone lives. Some countries have comprehensive regulations surrounding the handling of surplus embryos, including guidelines on informed consent and storage limits, while others have fewer rules in place, which leaves the decision largely down to clinics and individuals.^iv,v,vi

A Reproductive Endocrinology and Infertility (REI) specialist or fertility clinic can provide more information on local regulations surrounding the options for unused embryos.