Medications are used to stimulate the ovaries to make eggs.

IVF involves a carefully timed combination of medications designed to support egg development and prevent ovulation from occurring too early. Before stimulation begins, some patients take pretreatment medications, most commonly birth control pills, for two to three weeks in the cycle prior to IVF. This helps coordinate follicle growth and improve the chance of retrieving mature eggs, which are required for fertilization. In patients with evidence of diminished ovarian reserve, such as low AMH, low antral follicle count, or elevated FSH, an estrogen priming cycle may be recommended instead. This approach uses estrogen pills or skin patches, along with a short course of subcutaneous Cetrotide injections, to support follicle development.

The main phase of treatment involves ovarian stimulation with injectable hormones called follicle stimulating hormone, or FSH. Common brand names include Gonal F, Follistim, and Menopur. Menopur also contains luteinizing hormone, or LH. These medications are taken for an average of eight to ten days, although the exact duration and dosing depend on how the ovaries respond. During this time, patients are closely monitored with bloodwork to measure hormone levels and vaginal ultrasounds to assess follicle growth. When the follicles are ready, a trigger injection, most commonly human chorionic gonadotropin or hCG, is given to support final egg maturation before retrieval.

Medications to prevent premature ovulation are also an important part of IVF. Some patients use Lupron, which may be started in the second half of the cycle before stimulation begins. Others use Cetrotide, which is added several days after FSH stimulation has started. In certain cases, a microdose Lupron protocol, also called the Microflare protocol, is selected. This involves small doses of Lupron given twice daily starting early in the stimulation cycle. Each medication plan is individualized to support the best possible response and outcome.

During IVF treatment, progress is closely monitored to ensure the ovaries and uterus are responding appropriately and to guide medication adjustments. Patients typically undergo frequent vaginal ultrasounds to measure the number and size of developing follicles in the ovaries and to assess the uterine lining. Blood tests are also performed to track hormone levels, including estrogen and sometimes progesterone, which provide important insight into how the ovaries are responding to stimulation. This combination of ultrasound and hormone monitoring allows the care team to tailor medications, optimize timing, and determine the ideal moment for the trigger injection and egg retrieval, all while prioritizing safety and the best possible outcome.

Hear more from Danielle Vitiello, Ph.D., M.D., Medical Director, Board-Certified in Obstetrics and Gynecology and in Reproductive Endocrinology and Infertility, about the kinds of medications we may recommend to our patients and why.

There are two ways to inseminate eggs so they may be fertilized. These are:

1. Standard Insemination (SI), which is placing 10,000 moving sperm with each harvested egg under a drop of oil in embryo culture media;
2. Intracytoplasmic Sperm Insemination (ICSI), which involves placing one sperm into each egg. ICSI is generally performed in cases where there are problems with sperm, such as low count, motility, or poor morphology; in cases of failed fertilization; and to maximize fertilization. Pre-Implantation Genetic Testing (PGT) will be done.

Following SI or ICSI, the culture plates (petri dishes) containing eggs and sperm are placed in the incubator and checked the next day for fertilization.

While most eggs fertilize successfully in the lab, it is possible that some or even all may not. If fertilization does not occur, your care team will review the cycle to understand potential factors and discuss next steps. Sometimes adjusting the timing, trying a different fertilization technique, or using additional testing can improve outcomes in future cycles. It is important to remember that this is not a reflection of your value or potential to conceive. IVF is a complex process and challenges can happen even in otherwise healthy patients. Your care team is here to support you, answer questions, and guide you through every step, ensuring the best possible plan moving forward.

Not every egg retrieved during IVF will successfully fertilize, and the number can vary depending on factors such as age, egg quality, and sperm health.

Embryologists carefully monitor each egg for signs of fertilization and early development, providing individualized attention to ensure the strongest embryos are selected for transfer or freezing. While the exact number may differ from cycle to cycle, every fertilized egg represents a potential step toward pregnancy, and your care team will keep you informed throughout this important stage.

Embryo transfer (ET) occurs on the fifth day following fertilization and is performed under ultrasound guidance. The transfer is not painful but is generally uncomfortable because it is performed after drinking a liter of water to fill the bladder. A full bladder makes it easier to see the uterus under ultrasound guidance and pushes the uterus down so it is easier to accomplish the transfer. A two-stage process is performed by placing an outer catheter into the uterus and then loading the embryo into a transfer catheter, which is threaded through the outer catheter to approximately 2cm from the top of the uterus. At that point, the plunger on the syringe that is attached to the catheter and the embryo is injected.  In the past, many centers advised patients to have a ‘mock’ or pretend transfer to determine whether the transfer would be difficult. This is no longer necessary as the two-stage technique and ultrasound guidance obviate the need for a ‘mock’ transfer.

How many embryos to transfer depends on many clinical variables, but, in general, an elective single embryo transfer is performed in all women 37 years of age or younger. Remaining embryos of suitable quality can be vitrified (frozen) for later use, if necessary.

Following the transfer, it is not necessary to lie down for more than a minute. A study from Spain showed that higher pregnancy success rates were achieved if the woman got up following transfer compared to lying down for 10 minutes or more. A pregnancy test is performed 10 days following transfer. Most centers continue estrogen and progesterone therapy through this time and into early pregnancy.