Understanding the IVF Process Step by Step

Overview

This guide is the foundational, mechanics-focused piece in our fertility cluster — a real walkthrough of what IVF actually involves, stage by stage, for anyone who hasn't been through it and wants to understand the process before researching specific clinics or destinations. The other guides in this cluster cover cost, legal considerations, and what to ask a clinic; this one covers what actually happens during a cycle, with real timeframes.

What this guide covers

Stimulation and monitoring

Trigger shot and egg retrieval

Fertilization: conventional insemination vs. ICSI

Embryo culture and grading

Embryo transfer: fresh vs. frozen

The two-week wait, and when a cycle gets cancelled

Stimulation and monitoring

Before stimulation begins, some patients are prescribed birth control or estrogen for a short period beforehand — this isn't contradictory, it's used to prevent ovarian cysts and control the timing of the cycle so retrieval can be scheduled precisely.

The stimulation phase itself typically lasts 8-14 days. You'll self-administer injectable hormone medication daily to encourage multiple eggs to mature at once, rather than the single egg a natural cycle produces. During this window, you'll have monitoring appointments — ultrasounds and bloodwork — every few days so your clinic can track how your follicles are developing and adjust your medication dose in real time. This is also the phase that determines your actual trip length if you're treating abroad, since these appointments generally need to happen in person; see our fertility treatment abroad guide for how clinics typically structure this.

Trigger shot and egg retrieval

Once your follicles reach maturity (generally over 14mm), you'll get instructions for a final "trigger shot" — a hormone injection timed precisely 36 hours before your scheduled egg retrieval. This precision matters: the trigger shot is what causes final egg maturation, and retrieval is timed to happen right before those eggs would be released naturally.

Egg retrieval itself is a short procedure done under sedation, using an ultrasound-guided needle to collect eggs from the follicles. Most patients don't experience this as a major recovery event, though clinics generally recommend arranging a ride home and taking it easy for the rest of that day.

Fertilization: conventional insemination vs. ICSI

The day after retrieval, your eggs are fertilized using one of two methods, and which one your clinic uses is worth understanding:

Conventional insemination places multiple sperm in a dish with each mature egg and lets fertilization happen the way it would naturally, without manual intervention — generally used when sperm parameters (count, motility) are normal.

ICSI (intracytoplasmic sperm injection) involves an embryologist manually injecting a single sperm directly into each egg using a microscopic needle. This is typically recommended for male-factor infertility (low sperm count or motility) or after a previous cycle had unexpectedly low fertilization with conventional insemination.

On average, about 70% of mature eggs fertilize successfully, regardless of which method is used — a useful number to keep in mind, since not every egg retrieved is mature, and not every mature egg fertilizes.

Embryo culture and grading

Fertilized eggs (now embryos) are cultured in the lab for 5-6 days, with embryologists monitoring their development and assigning a grade based on how they're progressing. On average, about 50% of fertilized embryos progress to the blastocyst stage — the stage at which embryos are generally considered strong candidates for transfer or freezing. This is one of the more emotionally difficult parts of the process for many patients: starting with a number of retrieved eggs and watching it narrow at each stage (mature eggs → fertilized → blastocyst) is normal, not a sign that anything went wrong.

Embryo transfer: fresh vs. frozen

Embryo transfer itself is a quick procedure — generally under 10 minutes, done without sedation, placing the embryo directly into the uterus via a thin catheter.

Fresh transfer happens 3-7 days after retrieval, using an embryo from the same cycle. Frozen embryo transfer (FET) uses a previously frozen embryo, transferred in a separate, later cycle.

A common assumption is that fresh transfer must be more effective, since it skips the freeze-thaw step — but a peer-reviewed study found live birth rates of 50.2% for fresh transfer versus 48.8% for frozen transfer, a difference that isn't statistically significant for patients with normal ovulation. The same research found a real advantage to frozen transfer: it meaningfully reduces the risk of ovarian hyperstimulation syndrome, since the transfer happens in a later cycle after hormone levels from stimulation have settled. Which approach is right for you is a genuinely individual decision your clinic should walk through with you, not a default either way.

The two-week wait, and when a cycle gets cancelled

After transfer, most patients wait 9-14 days before a blood test can reliably confirm pregnancy — commonly called the "two-week wait," and often the most emotionally difficult stretch of the whole process, since there's genuinely nothing more to do but wait.

It's also worth understanding upfront that not every cycle reaches transfer. The most common reason a cycle is cancelled before retrieval is poor ovarian response to stimulation — put simply, too few follicles developing to justify proceeding with retrieval. (One clinic's specific criteria, cited here only as an illustration of the general concept rather than a universal standard: cancelling if fewer than 3 mature-size follicles are visible on ultrasound.) A less common reason is the opposite problem — an excessive response that raises OHSS risk. Neither outcome is a reflection of anything you did; response to stimulation varies by age, ovarian reserve, and individual biology, and a cancelled cycle is something your clinic should walk you through, including what it means for your next steps.

How VouchX helps

Understanding what actually happens during a cycle — not just the cost or the destination — puts you in a much stronger position to ask specific, informed questions of any clinic you're considering. Through VouchX's matching flow, you can bring your own situation and get matched with clinics ready to walk you through exactly how they'd handle each of these stages for you.

Get my 3 best matches → — five short questions, about 90 seconds.