Not sure which best fertility specialist you need?
Message our care team on WhatsApp. Tell us what’s going on and we’ll help you find the right best fertility specialist — free, with no obligation.
Chat with our care team on WhatsAppNot sure who to see? Find the right specialist →
In a medical emergency, or for severe or sudden symptoms such as breathing difficulty, chest pain, fainting or stroke signs, call 995 immediately.
Coming to Singapore from overseas for treatment? See our guide for international patients — costs, visas, travel and language support — or chat with our care team on WhatsApp.
At a glance
- ICSI (intracytoplasmic sperm injection) is a laboratory technique used during IVF.
- A single, carefully selected sperm is injected directly into each mature egg.
- It is mainly used for male-factor infertility or when previous IVF fertilisation failed.
- It overcomes problems with sperm reaching or entering the egg.
What ICSI is
ICSI is a specialised form of IVF. In a standard IVF cycle, prepared sperm and collected eggs are placed together in a laboratory dish and left to fertilise on their own, much as they would inside the body. In ICSI, an embryologist takes a single, carefully selected sperm and injects it directly into a mature egg using a very fine glass needle under a high-powered microscope. The aim is to help fertilisation happen when the sperm might otherwise struggle to reach or enter the egg by itself. Everything else about the treatment — the medicines, the egg collection, the way embryos are grown, and the transfer to the womb — follows the usual IVF path. ICSI simply changes the single moment at which egg and sperm come together.
How ICSI differs from standard IVF
In standard IVF, eggs and prepared sperm are placed together in a dish to fertilise on their own. In ICSI, an embryologist injects one sperm into each egg under a microscope. The rest of the IVF process — ovarian stimulation, egg collection, embryo culture and transfer — is the same. Because the injection is done for each mature egg individually, ICSI is a more hands-on laboratory step that relies on the skill of the embryology team.
Who ICSI is used for
ICSI is chosen mainly for significant male-factor infertility — a low sperm count, poor movement, or an unusual shape that makes natural fertilisation unlikely. It is also used when sperm has to be retrieved surgically from the testicle because there is little or no sperm in the ejaculate. Another common reason is a previous IVF cycle in which the eggs failed to fertilise even though healthy-looking sperm and eggs were placed together. ICSI may also be suggested when only a small number of sperm are available, when frozen sperm samples are limited, or in certain situations where the fertility team wants to give each egg the best chance. Because it targets the moment of fertilisation, ICSI helps most when the difficulty lies with the sperm rather than the egg. Your specialist will look at your semen analysis, medical history, and any earlier treatment before advising whether it is likely to help.
How ICSI fits within an IVF cycle, step by step
An ICSI cycle follows the same stages as IVF, with the injection added in the laboratory:
- Ovarian stimulation. Hormone medicines are used over a number of days to encourage the ovaries to grow several eggs at once, rather than the single egg of a natural cycle. Progress is followed with ultrasound scans and blood tests so the dose can be adjusted and the timing judged.
- Egg collection. When the eggs are ready, they are collected in a short procedure under sedation or light anaesthetic. A fine needle, guided by ultrasound, gently draws the fluid and eggs from the ovaries.
- The ICSI step in the lab. The embryologist examines the collected eggs and selects the mature ones. A single healthy-looking sperm is picked and injected directly into each mature egg. The eggs are then kept in a special incubator and checked to see which have fertilised.
- Embryo culture. Fertilised eggs are grown in the laboratory over several days, during which the embryologist watches how the embryos develop and divide.
- Embryo transfer. Usually a single embryo is placed gently into the womb through the cervix in a quick, straightforward procedure that does not normally need anaesthetic. Any suitable spare embryos can be frozen for later use.
- The wait and the pregnancy test. After the transfer there is a waiting period before a pregnancy test can reliably show a result. This stretch of waiting is often the most emotionally testing part of the cycle.
Reassuringly, ICSI only changes how fertilisation happens in the laboratory. Once an embryo has formed and been transferred, the pregnancy and the baby develop in the same way as any other.
How sperm is obtained
For many couples, sperm is provided as a fresh sample on the day of egg collection, or from a sample that has been frozen and stored beforehand. When there is no sperm in the ejaculate, or the count is extremely low, sperm may be obtained directly from the testicle or the tubes behind it through a minor surgical procedure carried out by a specialist. Even a small number of sperm retrieved this way can be enough for ICSI, because only one sperm is needed for each egg. The team will explain which approach suits your situation and what any procedure involves.
Preparation and what to expect
Before a cycle, the couple usually has a semen analysis, blood tests, and scans, and both partners may be advised on general health — a balanced diet, staying active, avoiding smoking and excess alcohol, and reaching a healthy weight where possible. Treatment involves regular clinic visits for monitoring during stimulation, so it helps to plan around work and daily commitments. On the day of egg collection you will need someone to accompany you home after sedation. Some bloating, cramping, or light spotting can be normal in the days around collection. Your clinic will give clear instructions on medicines, timings, and who to contact with questions.
Success and realistic expectations
ICSI improves the chance of fertilisation when sperm quality is the barrier, but it does not by itself improve the quality of the eggs, and it cannot make an egg or embryo develop that was never going to. Overall success still depends heavily on the woman’s age, the number and quality of eggs and embryos, the underlying cause of infertility, and sometimes on factors that remain unclear. Importantly, ICSI is not automatically better than standard IVF for couples who do not have a sperm problem, and it adds an extra laboratory step. It helps fertilisation happen; it does not guarantee a pregnancy or a baby, and more than one cycle is sometimes needed. Setting expectations honestly at the start, together with your specialist, helps you prepare for the range of outcomes. You can read more about IVF success rates when weighing your options.
Risks to be aware of
ICSI carries the same risks as IVF in general. Ovarian stimulation can occasionally lead to the ovaries over-responding, a condition called ovarian hyperstimulation syndrome (OHSS), which causes swelling and fluid build-up and, when severe, needs medical care. Egg collection is a minor procedure but carries small risks of bleeding, infection, or discomfort. If more than one embryo is transferred there is a higher chance of a multiple pregnancy, which brings added risks for mother and babies, so single-embryo transfer is often preferred. There are also considerations specific to ICSI that a specialist will discuss with you, relating to how it bypasses the natural selection of sperm; these are best understood through an open conversation about your particular circumstances.
The emotional and practical side
Fertility treatment can be demanding, both emotionally and practically. The daily medicines, frequent appointments, the two-part waiting — first for eggs and embryos, then for a pregnancy test — and the uncertainty of the result can be stressful for individuals and couples alike. It is completely normal to feel hopeful one day and low the next. Support is available: fertility clinics can arrange counselling, and talking openly with your partner, trusted friends, or a support group can ease the strain. Looking after your emotional wellbeing is a genuine part of the treatment, not a distraction from it.
Where ICSI is done in Singapore
In Singapore, ICSI is carried out at licensed assisted reproduction (ART) centres, within both public and private hospitals, by fertility specialists working with trained embryologists. These centres are regulated under the Ministry of Health’s assisted reproduction framework, which sets standards for laboratory practice, safety, and the handling and storage of eggs, sperm, and embryos. HealthHub offers general information on assisted reproduction for people in Singapore. Choosing an accredited centre and a fertility specialist you trust means your care follows recognised standards.
When to see a doctor and red flags
A fertility specialist can advise whether ICSI is appropriate based on your semen analysis and history, as part of planning IVF treatment. During a cycle, seek urgent medical care if, after egg collection or during stimulation, you have severe tummy pain or bloating, breathlessness, reduced urination, or a rapidly swelling abdomen — these can be signs of ovarian hyperstimulation (OHSS). Also seek urgent care for heavy bleeding or a fever. If you are ever unsure, contact your fertility clinic promptly; they would far rather hear from you early.
Common questions
Is ICSI better than IVF?
It is better when sperm quality is the problem, but for couples without a sperm issue it does not necessarily improve success and adds cost.
Is an ICSI baby different from an IVF baby?
No. ICSI only changes how fertilisation happens in the lab; pregnancy and the baby develop as normal.
When is ICSI recommended?
Mainly for male-factor infertility, surgically retrieved sperm, or after failed fertilisation in standard IVF.
Related guides
Sources
- Ministry of Health Singapore — assisted reproduction guidelines.
- KK Women’s and Children’s Hospital — IVF and ICSI.
- HealthHub Singapore — assisted reproduction.
This article is for general information only and does not replace a consultation with a qualified doctor. Please seek personalised medical advice for your situation.