IVF is a process that involves the creation of an embryo outside the body, which is then transferred into a woman’s uterus. The embryo must be created and transferred within a certain period, otherwise, it will not have the chance to survive in the uterus.
A complete IVF cycle involves steps like ovarian stimulation, egg and sperm retrieval, fertilization, and finally embryo transfer. The process typically takes between two to three weeks, and more than one IVF cycle may be needed to realize successful outcomes.
Here are the stages of IVF
Stages of IVF: Preparatory Phase
Before starting IVF, it is customary for a medical center to obtain consent from involved parties, evaluate medical history and perform a physical examination to ensure a high probability of conception.
Various blood tests are also taken to detect and exclude infections that may be sexually transmitted and blood-borne.
Downregulating Natural Hormone Cycle
Downregulation is often the preliminary stage of a high stimulation IVF mechanism. The term downregulation refers to the use of medication to interrupt a woman’s natural menstrual cycle, in effect prompting artificial menopause.
Women who are experiencing ovulation are treated with prescription hormones at a suppressive dose. These are taken either in the form of self-administered daily medication or nasal spray, taken for about two weeks.
There are different medicinal protocols used to stimulate multiple ovulations aimed at producing multiple embryos. This is done at the start of an IVF cycle to stimulate the ovaries to produce multiple eggs at once.
Typically, a single egg is produced during ovulation each month. The IVF process requires multiple eggs to increase the chances of normal development after fertilization.
Some of the medications for ovarian stimulation include injectable medication that contains follicle-stimulating hormone (FSH), luteinizing hormone (LH), or a combination of both medications in some cases.
Ovarian stimulation is also achieved through medications for oocyte maturation. This may include human chorionic gonadotropin (HCG) or other medications taken to help the eggs mature once the follicles are ready for egg retrieval. These are generally taken after 8 to 14 days after ovarian stimulation begins.
In some cases, reproductive experts prescribe medication to prevent premature ovulation. This is done to prevent a woman’s body from releasing the developing eggs sooner than what is ideal for a successful outcome.
When the eggs are ready for retrieval, doctors recommend progesterone supplements to prepare the lining of the uterus, making it more receptive to implantation.
There are slightly varying timelines for these medications, and doctors work with individuals to determine what medications to use and when to use them.
Around 36 hours after a “trigger shot” to help the eggs mature, eggs are retrieved in an office-based procedure. The timing of the retrieval is critical because waiting too long can risk ovulation and the loss of viable eggs. It is a minor procedure that typically takes between 15 to 20 minutes.
Women are sedated and the eggs are extracted using a needle guided into each ovary using ultrasound to carefully retrieve the eggs from each follicle. The eggs are then kept in a culture medium, to which sperm is added later to achieve fertilization
Reports from reproductive experts and experienced women indicate that some cramps or a small amount of vaginal bleeding are common after the procedure. Doctors typically prescribe some medication for the cramping and pain to grant relief after the retrieval procedure.
If fertilization is to be done using a partner’s sperm, a semen sample is requested on the morning of the procedure. If donor sperm is to be used in a certain case, it is harvested well in advance and frozen in a sanitary environment.
In most circumstances, a semen sample is collected through masturbation. However, depending on various fertility and health factors in general, sperms may be harvested surgically in a procedure known as testicular aspiration. Sperm is then separated from semen fluid by experts in a laboratory.
This is often attempted using two primary methods. These methods include;
Healthy eggs and sperm are mixed in a laboratory petri dish and left to incubate overnight, aimed at achieving natural fertilization.
Intracytoplasmic Sperm Injection (ICSI)
Standard insemination depends on the availability of between 50,000 to 100,000 motile sperm. If the sperm parameters are abnormal, ICSI is used to pick a single sperm with microneedles which are injected into the cytoplasm. Reproductive specialists inject the sperm into the oocyte using a high-power microscope.
Intracytoplasmic Sperm Injection allows fertilization to occur in the presence of disorders like oligospermia, asthenospermia, teratozoospermia, and azoospermia. Thus, ICSI increases the chances of fertilization if the semen sample shows low sperm count, motility, poor morphology, or progression.
The fertilized eggs henceforth referred to as embryos, are allowed to develop in the laboratory setting for up to 6 days before being transferred.
The healthiest one or two embryos are then selected for transfer, and any remaining healthy embryos are frozen and stored safely in case they are needed for use in later cycles.
Embryos are transferred into the womb using a catheter, a thin medical tube passed into the vagina. The process is relatively straightforward compared to egg collection and thus does not require one to be sedated.
The number of transferred embryos depends on the age and health of a woman undergoing the process. Up to three embryos are transferred for women above the age of 40, while up to two embryos are used per cycle for women under the age of 40.
After embryo transfer, progesterone supplements are recommended until a positive pregnancy diagnosis is confirmed by testing within 12 to 14 days of the transfer.
Stages in IVF are a complex medical process that involves retrieving eggs from a woman’s ovaries and fertilizing them with sperm in a laboratory environment. The process has several steps, all of which are central to the successful outcome of conception.
IVF is incredibly popular in traditional pregnancy and surrogacy alike. Find out more about IVF from our surrogacy community to learn more about the medical process and how it can play a role in your life.