What Is IVF? A Clear Step-by-Step Guide
IVF (In Vitro Fertilisation) is a fertility treatment where eggs are collected from the ovaries, fertilised by sperm in a laboratory, and the resulting embryo is transferred back into the uterus. It is the most effective form of assisted reproduction, accounting for over 99% of all ART cycles globally.
Who Is IVF For?
IVF is recommended for: blocked or damaged fallopian tubes; severe male factor infertility (used with ICSI); failed ovulation induction or IUI; unexplained infertility after 2–3 years; moderate-to-severe endometriosis; diminished ovarian reserve; women over 38 where IUI is time-inefficient; and couples needing embryo genetic testing (PGT-A or PGT-M).
Step-by-Step: The IVF Process
Step 1 — Baseline Assessment (Day 2–3 of cycle) Blood tests (FSH, LH, E2, AMH) and transvaginal ultrasound (antral follicle count) determine your medication doses and expected response.
Step 2 — Ovarian Stimulation (Days 2–12) Daily FSH injections (Gonal-F, Menopur, Fostimon) stimulate multiple follicles. A GnRH antagonist (Cetrotide, Orgalutran) prevents premature ovulation. Monitoring scans every 2–3 days track follicle growth (target: 8–15 follicles ≥14mm).
Step 3 — Trigger Injection (Day 10–12) When follicles reach 17–20mm, a trigger injection (hCG or GnRH agonist) finalises egg maturation. Retrieval is timed exactly 34–36 hours later.
Step 4 — Egg Retrieval (OPU) A 15–20 minute procedure under sedation. A needle guided by transvaginal ultrasound aspirates fluid from each follicle. Eggs are identified immediately by the embryologist. Most patients go home the same day with mild cramping.
Step 5 — Fertilisation Conventional IVF: 50,000–100,000 sperm placed with each egg; fertilisation occurs naturally. ICSI: A single sperm injected directly into each egg — used for male factor, low counts, or previous fertilisation failure. Fertilisation confirmed 16–18 hours later.
Step 6 — Embryo Culture (Days 3–6) Fertilised eggs develop in the incubator. Most clinics culture to Day 5 blastocyst stage — blastocysts have significantly higher implantation rates than Day 3 embryos (40–60% vs 20–35% per ESHRE 2023).
Step 7 — Preimplantation Genetic Testing (Optional) Blastocysts can be biopsied and tested for chromosomal errors (PGT-A) or inherited conditions (PGT-M). Results take 7–14 days; embryos are frozen and transferred in a later cycle.
Step 8 — Embryo Transfer One embryo is placed into the uterus through a thin catheter — a painless 10-minute procedure. ASRM and ESHRE recommend single embryo transfer (SET) for most patients to minimise twin risk.
Step 9 — The Two-Week Wait Progesterone support maintains the uterine lining. Beta-hCG pregnancy blood test is done 11–14 days after transfer.
How Long Does IVF Take?
- Pre-treatment assessment: 2–4 weeks
- Stimulation phase: 10–14 days
- Egg retrieval to Day 5: 5 days
- Two-week wait: 11–14 days
- Total per cycle: approximately 5–6 weeks
If PGT-A testing is done, embryos are frozen and transferred in a separate cycle — adding 4–6 weeks.
IVF Success Rates (ESHRE 2023, live birth per egg collection)
| Age | Live Birth Rate |
|---|---|
| Under 35 | 40–50% |
| 35–37 | 30–40% |
| 38–40 | 20–28% |
| 41–42 | 10–15% |
| 43–44 | 5–8% |
| Donor eggs | 40–50% any age |
Cumulative success rates across 3 cycles reach 60–70% for women under 40.
Reference: ASRM 2023 — In Vitro Fertilization. ESHRE Guideline — Ovarian Stimulation for IVF/ICSI, 2023.
Frequently Asked Questions
What is IVF in simple terms?▾
IVF means fertilising eggs with sperm outside the body. Eggs are collected from the ovaries after hormone stimulation, combined with sperm in a laboratory, and the resulting embryo is transferred back into the uterus. One cycle takes approximately 5–6 weeks.
Is IVF painful?▾
The daily injections are mildly uncomfortable. Egg retrieval is done under sedation and most patients feel period-like cramping afterwards. The embryo transfer is usually painless — similar to a cervical smear. Most patients find the emotional stress of waiting for results more difficult than the physical procedures.
How many IVF cycles does it take to get pregnant?▾
Most successful IVF pregnancies occur within 2–3 cycles. Cumulative live birth rates across 3 cycles are 60–70% for women under 40 (ESHRE data). Per-cycle success depends primarily on age. A fresh egg collection plus 2–3 frozen transfers from surplus embryos can constitute multiple attempts from one stimulation.
What is the difference between IVF and ICSI?▾
In conventional IVF, 50,000+ sperm are placed with each egg and fertilisation happens naturally. In ICSI, a single sperm is injected directly into each egg. ICSI is used for male factor infertility, low sperm counts, or previous failed fertilisation. Most Indian clinics use ICSI for all IVF cycles.