In vitro fertilisation (IVF) 2025: indications, process, evidence, risks & decisions

Author photo
Zappelphilipp Marx•
Embryologist checking embryo culture under a microscope in an IVF laboratory

In vitro fertilisation (IVF) is a standardised procedure in assisted reproduction. After hormonal stimulation, oocytes are retrieved, brought together with sperm in the laboratory, and transferred to the uterus as embryos. This article provides precise, level-headed guidance without exaggeration: indications, realistic success factors, the clinical pathway, safety aspects, the role of adjunct procedures, and how IVF differs from ICSI and IUI.

What is IVF?

Under controlled stimulation, multiple follicles mature. Mature oocytes are aspirated, incubated with prepared sperm, and cultured further. A suitable embryo is transferred; additional good-quality embryos can be cryopreserved. A clear patient overview is provided by the public health portal NHS.

Who is IVF suitable for?

  • Tubal factors (blocked or severely damaged fallopian tubes).
  • Endometriosis with a relevant impact on fertility.
  • Unexplained infertility after several well-planned IUI cycles.
  • Selected male-factor issues where conventional IVF appears sufficient; with pronounced impairment, often ICSI.
  • Fertility preservation and donor treatments according to local law and medical counselling.

Principle: the method follows the diagnosis. Proceed stepwise, avoid unnecessary complexity, and document decision pathways.

Evidence & success rates

The chance of a live birth per cycle is chiefly determined by age and oocyte quality, the cause of infertility, embryo quality, and the transfer strategy. National guidance recommends discussing expectations by age and by centre; figures vary between centres and cohorts. A sober overview of realistic expectations and how to avoid unproven extras is available from NICE.

Step-by-step process

  • Preparation: History, investigations, infection screening; discuss alternatives, chances, and risks.
  • Stimulation & monitoring: Individual dosing, ultrasound and hormone tracking; active OHSS prevention.
  • Follicle puncture: Retrieval of mature oocytes under ultrasound guidance.
  • Semen collection/preparation: Selection of motile sperm; partner or donor sperm per standards.
  • Fertilisation: Conventional IVF (co-incubation) or—where clearly indicated—ICSI.
  • Embryo culture: Assessment of development, possibly culture to blastocyst.
  • Embryo transfer: Transfer of a suitable embryo; number according to guidance, age, and embryo quality.
  • Cryopreservation: Freezing of additional suitable embryos/oocytes.
  • Luteal phase & test: Progesterone support; pregnancy test about 10–14 days after transfer.

Patient-friendly, step-by-step information is also provided by an NHS centre: Guy’s & St Thomas’.

Embryo culture & transfer

The goal is a healthy singleton pregnancy with the lowest possible risk. Where feasible, professional societies recommend single embryo transfer (SET) to avoid multiple pregnancy. Guidance on embryo number and timing of transfer is provided by the European society ESHRE: Embryo transfer guideline.

Risks & safety

  • Stimulation: Ovarian hyperstimulation syndrome (OHSS)—now rarer thanks to modern protocols, trigger strategies, and “freeze-all”, but still requires active prevention.
  • Procedures: Rare bleeding/infection after retrieval; post-transfer symptoms are usually mild and transient.
  • Multiple pregnancy: Higher risk when transferring more than one embryo; hence SET is preferred.
  • Psychological load: Cycle-related stress is common; plan structured counselling and psychosocial support.

Public information bodies such as HFEA and the NHS recommend clear stopping criteria when OHSS risk is present and a conservative embryo number per transfer.

Lab add-ons: what is evidenced?

Many add-ons do not reliably increase live-birth rates for most patients. The UK regulator assesses add-ons transparently and advises restraint unless there is a clear indication: HFEA add-ons.

Comparison: ICI · IUI · IVF · ICSI

CriterionICIIUIIVFICSI
PrinciplePlacement of the sample near the cervixWashed sperm into the uterusOocyte and many sperm in the laboratoryA single sperm is injected into the oocyte
Typical indicationEntry option without severe factorsUnexplained infertility, mild male factors, donor spermTubal factors, endometriosis, unsuccessful IUIPronounced male factor, fertilisation failure
Per-cycle successRather low, timing-dependentModerate; depends on age/diagnosisHigher than IUI; age-dependentSimilar to IVF; advantage mainly with male factor
ComplexityLowLow–mediumMedium–highHigh (micromanipulation)
Main risksSmall; hygiene/testing are centralMultiple-pregnancy risk with stimulationOHSS, procedural risks, multiplesAs in IVF + potential cellular damage

Consequence: use ICSI selectively for a clear indication; use IUI as a stepwise entry; if success is lacking, transition in a structured way to IVF/ICSI.

Planning & good practice

  • Clarify indication, alternatives, and objectives transparently; discuss expectations by age.
  • OHSS prevention: measured stimulation, appropriate trigger strategy, consider “freeze-all” when at risk.
  • Prefer single embryo transfer to minimise multiple-pregnancy risk.
  • Evaluate add-ons critically and use only with a plausible indication; rely on transparent evidence.
  • Define switch criteria: number of cycles, adjustments, and, if needed, changing method or pausing.

For guidance and patient information, NHS, NICE, and ESHRE are suitable sources. A small number of vetted references in text is sufficient.

RattleStork – well-prepared decisions around IVF

RattleStork is not a clinic and does not replace medical advice. The platform supports personal organisation: verified profiles and secure messaging, private notes on appointments, medications, and questions for the care team, as well as simple checklists for consultations and decision-making. This keeps information together—from the first appointment to embryo transfer.

RattleStork app showing verified profiles, secure chat, and private notes for IVF planning
RattleStork: Find support, organise information, and make well-informed IVF decisions.

Conclusion

IVF is an effective, well-standardised procedure. The main drivers of success are age, cause, embryo quality, and a cautious transfer strategy. Safety comes from modern stimulation protocols, clear OHSS prevention, single embryo transfer, and a critical approach to add-ons. Informed decisions and structured planning improve the chances—at the lowest possible risk.

Disclaimer: Content on RattleStork is provided for general informational and educational purposes only. It does not constitute medical, legal, or other professional advice; no specific outcome is guaranteed. Use of this information is at your own risk. See our full Disclaimer.

Frequently Asked Questions (FAQ)

The likelihood of success per cycle depends mainly on age, ovarian reserve, the cause of infertility, and embryo quality; laboratory quality, transfer strategy, and factors such as endometrial thickness and timing also influence outcomes, so centres often give age- and finding-dependent ranges rather than a fixed percentage.

In IVF, oocytes are co-incubated with many sperm, whereas in ICSI a single sperm is injected directly into the oocyte; ICSI is used primarily for pronounced male-factor issues or previous fertilisation failure and typically offers no benefit without such reasons.

In most situations, a single-embryo transfer is recommended because it combines the chance of live birth with the lowest multiple-pregnancy risk; multiples increase maternal and neonatal risks and are therefore avoided where possible.

With blastocyst transfer, embryos are cultured to day 5 or 6 and then transferred, allowing more precise selection; whether this improves success depends on oocyte yield, embryo development, and laboratory performance, and is not uniformly advantageous for everyone.

A frozen embryo transfer can be advantageous when there is OHSS risk or when the endometrium can be prepared more favourably in a later cycle; with good baseline conditions, a fresh transfer can be equivalent, and the decision depends on findings and centre practice.

Relevant risks include ovarian hyperstimulation syndrome, rare complications after retrieval, possible multiple pregnancy if more than one embryo is transferred, and psychological stress; with a tailored protocol, single-embryo transfer, and close monitoring, risks can be markedly reduced.

Follicle retrieval is usually performed under sedation and is generally well tolerated; mild cramping or a pressure sensation may last one to three days, and most patients can resume everyday activities promptly if no complications occur.

A review is often undertaken after two to three well-conducted cycles with adequate embryo yield and an optimised luteal phase; depending on age, findings, and prior results, adjustments such as protocol changes, different triggers, embryo number, or a switch to adjunct procedures may be considered.

PGT-A can aid embryo selection in selected situations but does not consistently improve live-birth rates across all groups; benefit depends on age, number of embryos, laboratory quality, and the clinical question, and should be weighed individually.

Many add-ons show no consistent live-birth benefit in studies; they should be used only with a clear indication and after a transparent benefit–risk discussion, with evidence-based counselling being essential.

With increasing age, oocyte quality declines and embryo aneuploidy rises, reducing fertilisation, implantation, and live-birth rates; markers such as AMH and antral follicle count estimate expected egg yield but do not reliably predict embryo quality.

Beyond stopping smoking and moderating alcohol, adequate sleep, regular physical activity, a healthy body weight, balanced nutrition, and stress reduction help; supplements should be targeted and used following medical advice.

With “freeze-all”, all suitable embryos are frozen and transfer is postponed to a later cycle, for example to prevent OHSS, with suboptimal endometrial preparation, or when additional diagnostics are planned; the approach can enhance safety and simplify planning.

Time-lapse systems allow continuous observation and can support embryo assessment, but a general live-birth benefit has not been shown for everyone; usefulness depends strongly on laboratory processes and selection algorithms.