what are the different forms of assisted reproductive technology?
If you have been struggling to start a family due to infertility issues, you may have looked into different types of assisted reproductive technology (ART) that can help increase your chances of pregnancy. According to the Center for Disease Control, ART involves procedures and fertility treatments that specifically involve the handling of eggs and embryos, although other definitions can encompass procedures beyond these types of interventions. This article will provide a general overview of the types of ART that offer patients with higher chances of having a healthy pregnancy and birth.
In Vitro Fertilization (IVF)
In vitro fertilization (IVF) is one of the most effective fertility treatments available, though it is also the most expensive and physically taxing. During the IVF process, eggs are surgically removed from a woman’s ovaries, combined with sperm to form embryos in a lab, and then an embryo is transferred into a woman’s uterus with the hope that it will develop into a healthy fetus. IVF is a suitable treatment option for women who have poor egg quality or low egg supply, irregular or no ovulation, blocked fallopian tubes, or issues with her endometrium, as well as men with low quality sperm.
In the first step of IVF, a woman undergoes treatment for ovulation induction, in which she receives hormone injections that stimulate the follicles in the ovaries to grow and mature multiple eggs. These fertility medications might be taken for several weeks, during which hormone levels and the production of eggs are monitored through blood tests and ultrasounds.
The next step of the process is egg retrieval. After a satisfactory number of follicles in the ovaries have grown to a certain size, the patient will take a drug to cause the eggs in those follicles to mature. Around 36 hours later, the fertility doctor will conduct a minor surgical procedure to retrieve these mature eggs. The procedure involves light sedation or anesthesia, and a doctor uses ultrasound to guide a needle into the follicles of the ovaries to retrieve the eggs stored inside. Only about 75% of the follicles that grew produce a mature egg that can be retrieved.
The eggs are then fertilized with sperm in one of two ways: either by surrounding the eggs with washed sperm, or by injecting one sperm cell directly into the egg in a process called intracytoplasmic sperm injection (ICSI). The decision of which technique is used to fertilize the eggs depends on several factors, such as whether the eggs were frozen or if the male has severe male factor infertility. The newly formed embryos then grow for a period of 3-7 days, which is usually the part of the process in which the most eggs and embryos are lost. At this stage, patients can also decide whether to test the embryos for chromosomal abnormalities in a procedure called comprehensive chromosome screening (CCS), or pre-implantation genetic testing (PGT).
The final step is embryo transfer, in which one or more embryos are non-surgically transferred into the uterus. This stage requires several decisions to be made, such as whether the embryos should be transferred “fresh” or be frozen for later use, which embryos should be transferred, and how many embryos should be transferred. Transferring two embryos increases the chances that the transfer will successfully result in a live birth, but also increases the risk of multiple pregnancies which can be harmful to both the mother and baby.
After the embryo is transferred to the uterus, it must implant within the uterine wall for the woman to become pregnant. Around 75% of embryos that are chromosomally normal successfully take hold. The patient will return to the clinic 8 or 9 days after the transfer to check if their levels of hCG, a pregnancy hormone, have increased to indicate a successful pregnancy. The pregnancy will then be monitored by the patient’s doctor until birth.
Intracytoplasmic Sperm Injection (ICSI)
Intracytoplasmic sperm injection (ICSI) is a method of egg fertilization that may be used instead of conventional fertilization during IVF. ICSI is a microsurgery in which a single, promising sperm cell is injected into an egg for fertilization.
Because it’s such a delicate procedure, injecting the egg with a sperm cell poses the risk of damaging the egg. However, there are certain instances in which ICSI can be beneficial, such as if the male has moderate to severe male factor infertility, or poor sperm morphology. ICSI might also be used for patients who have a history of fertilization failure, are using frozen eggs or sperm, or wish to use pre-implantation genetic testing.
Intrauterine Insemination (IUI)
Intrauterine insemination (IUI), also known as artificial insemination, is a procedure in which sperm is delivered directly into a woman’s uterus, near the fallopian tubes. By bypassing the vagina and cervix, the sperm delivered by IUI is more likely to fertilize an egg in the fallopian tube, increasing the chances of pregnancy. Sometimes IUI can be supplemented with fertility medications that induce ovulation, or stimulate the ovaries to produce multiple eggs.
IUI is specifically meant to help patients with irregular periods or PCOS, men with slightly low motile sperm counts, women with one blocked fallopian tubes, single and lesbian women needing sperm, and some couples whose infertility is unexplained, along with a few other circumstances.8 For patients with these issues, IUI may prove to be more successful than simply timed intercourse or ovulation induction medications, while being less costly than IVF. IUI may not be a practical option for women with a low supply of eggs, two blocked fallopian tubes, or an inhospitable uterus, or for men with a severely low motile sperm count.
Third Party-Assisted ART
When traditional methods of assisted reproductive technology don’t successfully lead to pregnancy, individuals and couples may turn to third party-assisted ART. Sperm donation is an option for lesbian couples or single moms, as well as men who produce little to no sperm or have a genetic disease. The sperm that is donated can be used with either IUI or IVF. Egg donation is also a type of third party-assisted ART that can be used for women who do not produce healthy eggs. Surrogates or gestational carriers can be used for gay couples or single dads, or if a woman is unable to carry a pregnancy to term. Embryo donation can also by women who can experience the pregnancy and give birth to an adopted child.
Although there are many available forms of ART, each type of treatment has its advantages and risks that depend on your individual circumstances. However, ART provides hope for individuals couples struggling with infertility, and is a major reason why these patients are still able to have healthy children. If you are struggling to naturally conceive, it might be worth it to discuss with your doctor whether a type of ART is right for you.