Understanding In Vitro Fertilisation (IVF): Process, Guidelines, and Expectations
When other fertility treatments fail after several cycles, in vitro fertilisation (IVF) is often the recommended next step. At its core, IVF is the process of fertilising a woman’s egg with a man’s sperm in a laboratory setting to generate embryos, which are then transferred to the uterus.
Subfertility affects approximately 15% to 20% of couples trying to conceive. While the process can seem daunting, understanding the clinical steps and the latest medical guidelines can support patients navigate their journey with confidence.
The Step-by-Step IVF Process
Whether a patient is undergoing conventional IVF or IVF with intracytoplasmic sperm injection (IVF-ICSI), the general procedure follows a structured sequence of steps. The primary difference between the two is how the egg and sperm are joined.
- Controlled Ovarian Stimulation: The process begins by stimulating the growth and development of multiple follicles. This is typically achieved using gonadotrophins, which are often combined with a gonadotrophin-releasing hormone (GnRH) agonist or antagonist.
- Follicular Puncture: Once follicles are mature, they are retrieved from the ovaries.
- Collection and Preparation of Semen: Sperm is collected and prepared for the fertilisation process.
- Fertilisation: The egg and sperm are united. In conventional IVF, this happens naturally in the lab; in IVF-ICSI, a single sperm is injected directly into the egg.
- Checking Fertilisation: Specialists verify if the eggs have been successfully fertilised.
- Embryo Culture: The resulting embryos are grown in a controlled environment.
- Preparation of the Endometrium: The lining of the uterus is prepared to ensure the best environment for implantation.
- Embryo Transfer: One or more embryos are transferred into the uterus.
- Freezing Embryos: Any remaining viable embryos are frozen for future use.
- Pregnancy Test: A final test is conducted to confirm if the treatment was successful.
For a detailed breakdown of these stages, you can review the IVF process guide.
Pre-Treatment and Lifestyle Recommendations
Preparing the body for IVF can improve the overall experience and potential for success. Medical experts suggest specific lifestyle adjustments and adherence to evidence-based clinical guidelines.
Lifestyle Optimization
To optimize the chance of success, patients are encouraged to follow basic health recommendations, such as taking a daily multivitamin supplement that contains at least 400 mcg of folic acid, as recommended by the Massachusetts General Hospital Fertility Center.
Clinical “Do Not Use” Guidelines
Recent guidance from the National Institute for Health and Care Excellence (NICE) provides clear instructions on treatments that should not be offered as a means of improving IVF outcomes:
- Endometrial Scratch: This should not be offered as a pre-treatment to improve outcomes.
- Screening Hysteroscopy: This is not recommended as a pre-treatment to improve outcomes, though it remains necessary if uterine or endometrial abnormalities are suspected.
- Endometrial Receptivity Testing: This includes both gene expression analysis (such as the endometrial receptivity array) and microbiological analysis (such as metagenomic analysis of the endometrial microbiome).
- Immunological Agents: The use of steroids (glucocorticoids), intralipids, or intravenous immunoglobulins is not recommended as part of fertility treatment.
Comparing IVF Methods
Depending on the couple’s specific needs, different IVF protocols may be used. While standard IVF relies on controlled ovarian hyperstimulation (COH) to produce multiple eggs, some couples may opt for natural cycle IVF to avoid the risks and costs associated with intensive hormone therapy.
| Feature | Standard IVF (COH) | Natural Cycle IVF |
|---|---|---|
| Hormone Use | High (Gonadotrophins/GnRH) | Minimal to none |
| Egg Yield | Multiple follicles stimulated | Typically one egg |
| Risk Profile | Higher risk of adverse effects | Lower risk of stimulation side effects |
More information on the differences in approach can be found via the Cochrane Database of Systematic Reviews.
Key Takeaways
- IVF is a multi-step process involving ovarian stimulation, egg retrieval, laboratory fertilisation, and embryo transfer.
- IVF-ICSI is used when a more direct method of sperm injection is required.
- Folic acid (400 mcg) is a critical pre-treatment supplement.
- Modern guidelines (NICE 2026) advise against using endometrial scratches, receptivity testing, or immunological agents to improve IVF success rates.
- Subfertility affects 15% to 20% of couples, making IVF a vital tool for achieving pregnancy.
As reproductive medicine evolves, the focus remains on using evidence-based procedures that prioritise patient safety and genuine efficacy. Couples are encouraged to consult with their specialists to determine which protocol—whether standard or natural cycle—is best suited for their specific medical history.