IVF in Simple Terms: What Happens to Your Body and What Is Essential to Know Before Starting a Protocol

The decision to enter an In Vitro Fertilization (IVF) protocol is always a significant step, one that every woman and every couple approaches with their own unique experience, questions, and emotional state. Some have already studied the subject thoroughly and wish to understand the nuances. Others are just learning about the process. Still, others are seeking not just information, but support and the assurance that everything happening is clear and manageable. This article was written specifically for that purpose.

I want to discuss what an IVF protocol consists of, what happens to the body at each stage, and what to expect physically and emotionally. Not because it is a simple procedure, but because understanding each step helps one feel more confident and mindful on this journey. Over years of practice, I have become convinced: when a patient understands the logic behind what is happening, she interacts better with the physician, pays timely attention to important changes in her well-being, and overall undergoes treatment more consciously.

What is an IVF Protocol and What Does It Entail?

In Vitro Fertilization is a method of assisted reproductive technology (ART) in which the fertilization of the egg occurs outside the woman’s body, in laboratory conditions. The entire process is commonly referred to as a “protocol,” and it includes several clearly structured stages, each of which fulfills a specific clinical objective.

Within the framework of the protocol, monitored ovarian stimulation is performed to obtain several mature oocytes (eggs), followed by their surgical retrieval—follicular puncture. The retrieved eggs are fertilized in an embryology laboratory, where the embryos are cultured for several days under constant specialist supervision. After assessing the quality of the embryos, the most viable one is transferred into the uterine cavity. Subsequently, dynamic monitoring of implantation and pregnancy development is conducted.

A protocol typically begins on day 2–3 of the menstrual cycle and can be chronologically divided into two main phases:

1. Phase One: Ovarian stimulation followed by retrieval and fertilization. This period lasts an average of 10–14 days.
2. Phase Two: Embryo development (3–5 days), the long-awaited transfer into the uterine cavity, and the subsequent waiting period.

Following the transfer, a critical phase begins—approximately two weeks leading up to the blood test for Human Chorionic Gonadotropin (hCG), which allows to determine if pregnancy has occurred. Thus, the entire active process fits within a fairly predictable timeframe, where every step is precisely calculated and result-oriented.

Ovarian Stimulation and Hormonal Therapy: Key Insights

The ovarian stimulation phase often triggers the highest number of questions from patients. Concerns regarding daily injections, hormonal medications, and their potential impact on the body are entirely understandable and natural. It is vital that every woman has the opportunity to receive clear and detailed answers to these concerns.

In a natural cycle, the ovaries typically mature a single egg. In an IVF protocol, the goal is to obtain multiple mature oocytes; this increases the probability of obtaining high-quality embryos and improves the chances of a successful treatment outcome. To achieve this, hormonal medications from the gonadotropin group are prescribed to stimulate the ovaries to develop several follicles simultaneously. Medications are administered subcutaneously, most often in the abdominal area. The needles for these injections are very thin, and most patients describe the sensation as a minor pinch.

Throughout the stimulation, which lasts approximately 10–12 days, regular ultrasound monitoring of the pelvic organs is performed—typically every 2–3 days. This is necessary to track follicle growth dynamics and adjust medication dosages in a timely manner. It is essential to adhere to the appointment schedule and maintain contact with the attending physician throughout this period.

Possible side effects of stimulation include bloating, a feeling of heaviness or pressure in the lower abdomen, mood swings, and mild fatigue. All of these are expected bodily reactions to the hormonal load and generally resolve after the protocol is completed. However, if severe pain, significant abdominal distension, difficulty breathing, or a sharp decline in overall well-being occurs, it is imperative to inform the doctor immediately, as such symptoms may indicate Ovarian Hyperstimulation Syndrome (OHSS), which requires medical intervention.

Retrieval, Fertilization, and Embryo Transfer: Three Key Milestones

When the follicles reach the required size—typically 18–20 mm—an ovulation trigger is administered (an hCG trigger or a GnRH agonist), and exactly 34–36 hours later, follicular puncture is performed. This is a minimally invasive surgical procedure performed under intravenous anesthesia. Under ultrasound guidance, the contents of the follicles, along with the oocytes, are aspirated through the vaginal wall using a fine needle. The procedure lasts 15–30 minutes, after which the patient remains under medical observation for 2–3 hours. If the patient’s condition is stable, discharge occurs on the day of the procedure.

The retrieved eggs are handed over to the embryologist. On the same day, fertilization is performed: predominantly using the Intracytoplasmic Sperm Injection (ICSI) method, where a single sperm is injected directly into the egg. The following day, the embryologist assesses the fertilization results and informs the patient. The embryos grow in specialized culture media under the supervision of embryologists for 3–5 days—up to the blastocyst stage, which is optimal for transfer into the uterine cavity.

Embryo transfer is a painless outpatient procedure and does not require anesthesia. Prior to the transfer, to ensure clear visualization of the endometrium, a woman needs to drink plenty of fluids so that the bladder is full. This may cause slight discomfort; however, the bladder can be emptied immediately after the procedure.

During the procedure, the embryo is introduced into the uterine cavity via a thin, flexible catheter under ultrasound guidance. The manipulation takes only a few minutes, after which the patient can be discharged. Strict bed rest in the following days, contrary to popular misconception, is not clinically justified and does not affect the probability of implantation. Moderate daily activity is perfectly acceptable.

The Waiting Period After Embryo Transfer

After the embryo transfer, a period of dynamic observation begins, lasting about two weeks—until the day of the follow-up hCG blood test. This time often proves to be the most emotionally taxing for patients. The body may exhibit a wide range of reactions during this period—from pronounced symptoms to their complete absence. Both scenarios fall within the normal range.

Some women note sensations characteristic of early pregnancy: breast tenderness, pulling discomfort in the lower abdomen, and increased sensitivity. Other patients do not notice any subjective changes—and this likewise does not indicate a lack of implantation. It must be considered that progesterone medications prescribed after the transfer are themselves capable of mimicking sensations indistinguishable from early pregnancy symptoms. This is why the only reliable method for evaluating the result is the quantitative hCG testing in the blood on the scheduled day.

During this period, it is recommended to exclude intense physical activity, thermal procedures (saunas, hot baths), and alcohol consumption. The question of sexual activity is decided individually—it should be discussed with the attending physician. Moderate physical activity, walking, and working in a routine mode are not contraindicated.

Regarding home pregnancy tests: their results in the first 10 days after transfer are often unreliable due to residual hCG from the administered trigger. This can lead to false-positive or false-negative results, complicating proper interpretation. Therefore, only the result of the blood test conducted on the day agreed upon with the physician is considered clinically significant.

When the Protocol Does Not Result in Pregnancy

This is one of the most difficult conversations in reproductive medicine—and I want to approach it with the thoroughness and sensitivity it deserves. For many couples, a failed IVF protocol becomes a profound emotional experience, especially if there have been multiple attempts. Such a reaction is absolutely natural and understandable. According to global statistics, the success rate of a single fresh embryo transfer in women under 35 is approximately 40–50%; that is, even with flawlessly executed treatment, pregnancy does not occur in every case. This does not mean that anything was done incorrectly—neither by the patient nor the physician.

After every cycle that ends without a pregnancy, a detailed analysis of all parameters is conducted: the quality and development of the embryos, the state of the endometrium, the hormonal profile, and immunological indicators are assessed. Often, it is this data that allows for the adjustment of future tactics and improves the effectiveness of the next protocol. Most patients who achieve pregnancy through IVF have undergone more than one treatment cycle—and it is important to understand this when deciding whether to continue therapy.

A repeat protocol typically becomes possible 1–3 months after the previous one—the timing is determined individually, taking into account the patient’s health and examination results. If embryos were obtained and frozen during the previous cycle, the next step may be a frozen embryo transfer (FET) protocol—which is significantly less taxing, as it does not require repeated ovarian stimulation. This is a distinct and very important topic that deserves a separate article.

The Emotional Side of the Protocol and the Support That Matters

An IVF protocol places significant demands on physical, emotional, and temporal resources. Having a partner or a loved one nearby who understands the essence of what is happening is of great importance. Speaking openly about one’s feelings and concerns helps reduce the emotional tension that often intensifies during periods of isolation and silence. If at any point the need for psychological support arises, it is a completely justified and sensible decision. Many clinics offer psychological counseling as part of reproductive programs precisely because the patient’s emotional state is an integral part of the treatment.

Awareness of each stage of the protocol allows the patient to feel like a full participant in the medical process. Any question that arises during the protocol deserves a detailed and attentive answer. The better a patient understands the logic of the prescriptions and procedures, the more confidently and mindfully she undergoes treatment.

The path to achieving pregnancy through assisted reproductive technologies can be long. Modern reproductive medicine possesses capabilities that were unavailable even two decades ago. A conscious approach to treatment, an understanding of each of its stages, and trust in the specialist accompanying this journey create the foundation upon which the result is built.

Article author: obstetrician-gynecologist, operating