IVF is short for in vitro fertilization. It means that rather than an egg being fertilized within the human body (known as in vivo fertilization), the egg is fertilized within a laboratory outside of the body. IVF is a common procedure in the world of fertility treatment, but it comes with lots of variations. The variations can come in the form of different insemination types, who is providing the eggs and sperm to create the embryos, whether or not you choose to do genetic testing, and eventually when and how you do an embryo transfer to try to get pregnant. We’ve broken down some of the possible types of IVF to help you understand many of the possibilities.
Conventional IVF
Conventional IVF is the most standard version of the process. In conventional IVF, you undergo ovarian stimulation using injectable fertility medications to grow multiple eggs in each ovary. After about 10-14 days of medications, when the eggs are likely mature, your doctor gives instructions to do the trigger shot. The trigger shot prepares the eggs to be retrieved during the egg retrieval procedure that happens 36 hours later.
In conventional IVF, the retrieved eggs are fertilized by a method known as conventional insemination. In conventional insemination, the sperm sample is combined with the eggs in the embryology lab. The sperm are allowed to naturally go about fertilizing the eggs without any assistance from the embryology team.
Mini IVF
Mini IVF is a form of IVF that uses lower doses of stimulation medications (sometimes oral, sometimes injectable, and sometimes a combination of both). One of the reasons why mini IVF is done is to limit the likelihood of a severe response to high-dose fertility medications called OHSS (most frequently seen in patients with very high egg count). Although standard IVF using doses on the lower side (but not low enough to be considered mini) is the more common way to treat these patients. The second reason behind doing mini IVF is that patients can save money in a few ways:
Using lower doses of injectables or using oral medications can save hundreds and sometimes even thousands of dollars in medication costs.
Some mini IVF cycle protocols require less frequent office visits resulting in lower monitoring fees.
With mini IVF, there is less likelihood of having extra embryos that need to be frozen, which also can reduce how much you are spending.
The actual savings of mini IVF varies per clinic and per treatment protocol.
Mini IVF does result in fewer mature eggs being retrieved at the egg retrieval, so there are fewer chances to create a normal embryo for transfer. Some doctors and clinics claim that mini IVF may result in higher quality eggs, but there is currently little research to confirm this.
It’s important to note that not all clinics offer mini IVF. If you think that mini IVF is something that you are interested in, talk with your doctor about your likelihood of success with mini IVF.
IVF with egg donation
IVF using donor eggs can happen one of two ways: frozen or fresh.
Frozen donor eggs
In the frozen case, an egg donor goes through ovarian stimulation for 10-14 days, and then eggs removed during the egg retrieval belong to the egg bank where they remain frozen. The donor eggs then can be purchased, thawed, fertilized, and eventually transferred into a person or couple who purchases them.
Fresh egg donor
Conversely, in a fresh egg donor IVF cycle, a person or couple chooses either a known or anonymous egg donor. The donor undergoes ovarian stimulation for 10-14 days, followed by an egg retrieval. The retrieved eggs are then fertilized by the sperm of the person or couple who selected this donor.
Purchasing eggs from an egg bank can speed up the IVF process because the eggs have already been retrieved and you know exactly how many eggs you are purchasing. Egg banks typically sell eggs in lots of 6 or 8. When doing a fresh donor cycle, starting treatment may take longer because you have to work around the schedule of the donor and there is no way of knowing exactly how many eggs you’ll get from the fresh donor cycle in advance. Your clinic can help guide you through your donor egg options to determine which route may be best for you.
IVF with ICSI
IVF with ICSI refers to the method in which the retrieved eggs are fertilized, known as Intracytoplasmic Sperm Injection. In IVF with ICSI, you undergo ovarian stimulation using injectable fertility medications to grow multiple eggs in each ovary. After about 10-14 days of medications, when the eggs are likely mature, your doctor gives instructions to do the trigger shot. The trigger shot prepares the eggs to be retrieved during the egg retrieval procedure that happens 36 hours later.
During ICSI, the embryologist holds each egg still, one at a time, using gentle suction through a glass pipette. Then they draw up one sperm into a tiny needle. Next, they puncture through the outer coating of the egg and inject the singular sperm into the cytoplasm of the egg. Finally, the needle is removed and the rest of the fertilization process (the combining of the sperm and egg DNA) is allowed to happen naturally.
ICSI is used in cases where fertilization has failed in past treatment cycles, in cases of male-factor infertility, and frequently in cycles where the embryos will undergo testing for specific genetic abnormalities.
Conventional Insemination (left) compared to ICSI (right)
IVF with donor sperm
IVF with donor sperm is very similar to conventional IVF, but instead of using the male partner’s sperm, a donor sperm sample is used. The 10-14 day IVF ovarian stimulation and egg retrieval portions are unchanged. There are a few times when donor sperm samples are commonly used:
Same-sex female couples
Male-factor infertility
Single mother by choice (SMC)
Donor sperm can be from a known donor or purchased from a sperm bank. Required testing and fees vary between each type of donor, so it is important to discuss your sperm source options with your doctor.
IVF with PGT
In IVF with PGT (Preimplantation Genetic Testing), you undergo ovarian stimulation for 10-14 days using injectable fertility medications. Once your doctor determines that the eggs are likely mature based on the size of the ovarian follicles, you’ll be instructed to take the trigger shot in preparation for the egg retrieval that takes place about 36 hours later. After the eggs are retrieved, they are inseminated either using conventional insemination or through an assisted insemination process known as ICSI. After the eggs are fertilized, they are now considered embryos. The embryos are allowed to culture in the lab for up to 7 days. Embryos that reach a stage known as Blastocyst on days 5, 6, and 7 of development are biopsied for PGT.
The biopsy consists of removing a few cells from the embryo’s outer portion, known as the trophectoderm. The trophectoderm cells will eventually become the placenta as the embryo continues to develop. The biopsied cells are sent out to a special laboratory that assesses the embryos to confirm that they are chromosomally normal (46XX for female or 46XY for male), determine the sex of the embryos, and in some cases determine if the embryos are affected by any genetic conditions that are carried by their parents.
Most people do not do an embryo transfer at the end of their IVF with PGT cycle. This is because it takes about 10-14 days to get your PGT results back, which is well beyond the window for a fresh embryo transfer to occur. Typically, the blastocyst embryos are biopsied, frozen, and a frozen embryo transfer (FET) is planned once the results of the PGT testing have been received.
If a fresh transfer is planned at the end of an IVF with PGT cycle, the embryo that is transferred will not have undergone genetic testing prior to transfer, but the remaining blastocyst stage embryos will be biopsied and frozen for later use.
Reciprocal IVF
Reciprocal IVF, also known as partner IVF, co-maternity, or simply RIVF, is a type of IVF involving same-sex female couples. During RIVF, one partner undergoes the 10-14 day ovarian stimulation where they use injectable stimulation medications to encourage their ovaries to grow multiple eggs to maturity. Once the doctor determines the eggs are ready for retrieval, they give instructions to take the trigger shot. The egg retrieval happens about 36 hours later. After the egg retrieval, the eggs are fertilized with donor sperm to create embryos that will grow in culture in the lab for up to 7 days.
The reciprocal part happens when it’s time to plan an embryo transfer. The other partner (the one who did not undergo ovarian stimulation to create the embryos) has the embryo transferred into their uterus to carry the pregnancy. RIVF is a great way for both partners to be able to physically play a role in the family building process.
IVF with a fresh transfer
The first half of IVF with a fresh transfer looks the same as a standard IVF cycle. You’ll undergo ovarian stimulation using medications for 10-14 days to get the ovaries to grow multiple eggs. When the eggs are mature, you’ll be instructed to take the trigger shot in preparation for the egg retrieval that takes place about 36 hours later. After the egg retrieval, the eggs are given to the embryology lab. Once the eggs are in the lab, they are fertilized either through conventional insemination or ICSI. The resulting embryos will culture in the lab for up to 7 days.
Simultaneously, after the egg retrieval happens, you’ll be instructed to begin taking estrogen and progesterone medications to prepare your body to transfer an embryo into your uterus. Depending on the embryo development, the embryo transfer typically takes place either 3 days or 5 days after the egg retrieval procedure. Your clinic will keep you updates about how your embryos are growing and when to come into the clinic for the embryo transfer.
Most times, your doctor will transfer the single best graded embryo. This is known as an eSET (elective single embryo transfer). There are circumstances where providers may consider transferring more than one embryo, for instance in patients who have experienced recurrent pregnancy loss or implantation failure.
If you have more than one embryo, the remaining embryos will be frozen for later use. If you choose to, you can have genetic testing known as PGT done on the remaining embryos that reach the blastocyst stage.
IVF freeze all
IVF freeze all is essentially just an embryo freezing cycle. It is very similar to egg freezing, but rather than freezing eggs to use at a later date, you’ll fertilize the eggs and freeze embryos to use in the future. This means that you go through the IVF ovarian stimulation portion to stimulate the ovaries to create lots of mature eggs. Then, when the eggs are likely mature, the doctor gives instructions to do the trigger shot and the eggs are retrieved about 36 hours later and given to the lab for fertilization. The lab will do either conventional insemination or ICSI to create the embryos. The fertilization can be done using a partner sperm sample or donor sperm. The embryos will grow in culture in the embryology lab for up to 7 days. At that point, the embryos that make it to the blastocyst stage can be biopsied if you are doing PGT testing. Then the embryos are frozen.
In freeze all cycles, there is not necessarily any plan to transfer the embryos in the immediate future. Sometimes, freezing the embryos is considered more of a measure for fertility preservation. Freezing embryos gives a person or couple an open timeline to reach their family planning goals without as much pressure from their biological clocks. Once the embryos are created, they can remain frozen indefinitely, until you’re ready to plan a frozen embryo transfer to get pregnant.
Because there are so many variations, we’ve summarized some of the key differences in this table:
