IVF explained: the steps, who it is for, risks and what to expect

In vitro fertilisation, usually called IVF, is the best known fertility treatment. This article explains what it is, who it may suit, how a treatment cycle works and what risks to know about, using information from the NHS, the US CDC and MedlinePlus.

1. Introduction

The NHS describes IVF as a treatment in which eggs are fertilised with sperm in a laboratory and the resulting embryo is placed in the womb. It may be recommended if you are having difficulty getting pregnant and other treatments have not worked ^[1]. The CDC says IVF is the most common type of assisted reproductive technology (ART), a group of treatments in which eggs or embryos are handled to help achieve a pregnancy ^[2]. MedlinePlus calls it the most common and most effective form of ART ^[3].

MedlinePlus says assisted reproductive technology can use donor eggs, donor sperm or embryos that were frozen earlier, and may involve a gestational carrier, who becomes pregnant with the couple's egg and sperm ^[3]. The CDC says ART also includes freezing eggs and embryos and egg and embryo donation ^[2].

2. Who may be offered IVF

In the UK, the NHS says you may be able to have IVF on the NHS if you are 42 or under and eligible. The details are as follows ^[1]:

• Aged 39 or under: you may be eligible for 3 full cycles if you have tried to conceive through regular sex without contraception for at least 2 years, or have had 12 cycles of artificial insemination, at least 6 of them using intrauterine insemination (IUI). If tests show you are unlikely to conceive without IVF, you should be referred straight away.
• Aged 40 to 42: you may be eligible for 1 full cycle if you have tried to conceive for at least 2 years through regular sex without contraception, have had 12 cycles of artificial insemination with at least 6 using IUI, and have not had IVF before. Tests first check that your ovaries respond normally to fertility medicine, and your doctor will discuss the risks of IVF at this age.

Local integrated care boards decide who is funded, and some only offer IVF to people under a certain age, at a healthy weight, who do not smoke and who have no existing children. Private clinics usually set their own age or weight ranges and prices ^[1]. The NHS warns that clinics abroad may not be regulated to the same standard as in the UK, so check the rules and licensing wherever you plan to be treated ^[1]. If you live in India or the United States, ask your doctor which national rules and clinics apply to you.

3. The steps of an IVF cycle

The NHS says a full cycle takes about 3 to 6 weeks and usually has six steps ^[1]:

1. Switching off natural egg production. A daily injection or nasal spray for 2 to 3 weeks, with an ultrasound to check progress.
2. Boosting the egg supply. Daily self-injections for about 2 weeks, with monitoring.
3. Egg collection. A needle is passed through the vagina to collect eggs. It takes around 20 minutes, and a sedative may be offered.
4. Sperm sample. The partner gives a sample, or donor sperm is prepared in the laboratory.
5. Fertilisation. Eggs and sperm are combined in the laboratory, and the clinic calls the next day to say how many embryos there are.
6. Embryo transfer. A few days later, an embryo is placed in the womb through a thin tube passed through the vagina.

Before starting, you normally have blood tests, including for HIV and hepatitis B and C. You may be given the contraceptive pill or progestogen tablets to time treatment, and you must give consent. Spare suitable embryos may be frozen, which can carry extra storage costs. A pregnancy test is done about 16 days after transfer, and if it is positive a scan is usually arranged at around 7 weeks ^[1].

4. Risks

The NHS says IVF is generally safe and most people have no health or pregnancy problems, but there are risks ^[1]:

• Ovarian hyperstimulation syndrome (OHSS): enlarged, painful ovaries, which may mean stopping the cycle.
• Multiple pregnancy: more than one baby, which raises risks for the mother and babies. MedlinePlus says multiple pregnancy is the most common complication of assisted reproductive technology, and that limiting the number of embryos transferred can reduce it ^[3]. The NHS says the risks and benefits of transferring more than one embryo will be discussed with you ^[1].
• Ectopic pregnancy: the embryo implants outside the womb.

The NHS says IVF can affect you emotionally and physically, and recommends counselling for anyone having IVF ^[1]. MedlinePlus says counselling and support groups can help people with infertility ^[4].

5. How likely is IVF to work?

The NHS gives no single success figure. It says your chance of having a baby depends on the cause of your fertility problem, your age, your body mass index and lifestyle factors such as smoking and alcohol ^[1]. The CDC points readers to national clinic success rates and an online estimator, and a doctor can explain what the figures mean for you ^[2]. Statistics for a whole group cannot predict what will happen in one person's cycle.

6. When to see a doctor

See a fertility specialist or your doctor if you are thinking about IVF. During treatment, contact your clinic, or in the UK NHS 111, urgently for abdominal pain and bloating, nausea and being sick, feeling faint, coughing up blood, vaginal bleeding or brown watery discharge, or pain when passing stools or urine ^[1].

Seek emergency help without driving yourself for difficulty breathing, chest or upper back pain, severe thirst with passing little urine, swelling in any part of the body, shoulder-tip pain, or low tummy pain on one side ^[1].

In an emergency, call your local emergency number (112 in India, 911 in the United States).

7. Conclusion

IVF places eggs and sperm together in a laboratory and returns an embryo to the womb, usually over 3 to 6 weeks. The NHS describes it as generally safe, but it carries risks including OHSS, multiple pregnancy and ectopic pregnancy. The chance of a baby depends on age, the cause of infertility and lifestyle. A fertility specialist decides whether IVF is suitable for you and explains the benefits, risks and costs.