IMSI vs ICSI in IVF—Which Is Better for Male Infertility?

When couples walk into my clinic after failed IVF or ICSI cycles, one common question I hear is, “Doctor, is IMSI better than ICSI?”

It’s an important and valid question. As a fertility specialist, let’s break it down step by step so you can understand what each technique means, when IMSI is useful, and whether it can improve your chances of success.

Before moving ahead, it’s important to understand ICSI and IMSI.

ICSI stands for Intracytoplasmic Sperm Injection. It is one of the most widely used techniques in assisted reproduction. In this process:

• An embryologist selects a single sperm.

• The sperm’s tail is immobilized.

• It is injected directly into the egg (oocyte) under a microscope.

The microscope used in ICSI magnifies the sperm about 400 times, which is usually sufficient for fertilization in most patients.

IMSI (Intracytoplasmic Morphologically Selected Sperm Injection) is an advanced version of ICSI. It uses a special microscope with 6,000 times magnification (compared to 400 times in ICSI).

This high magnification allows us to:

• Closely examine the sperm’s head, tail, and overall structure.

• Identify tiny defects that are not visible under standard ICSI magnification.

• Select the healthiest sperm for injection.

IMSI is not for every patient. It is generally considered in specific situations:

• The male partner has poor sperm morphology (abnormal shape/structure).

• Previous low fertilization rates in ICSI cycles.

• Two or more failed ICSI attempts.

• History of embryo arrest (embryos stop developing).

• Severe male factor infertility, including azoospermia cases (when sperm is retrieved through TESE or microTESE).

These are the clinical situations where IMSI (Intracytoplasmic Morphologically Selected Sperm Injection) comes into use.

This is one of the most common questions patients ask. Let’s break it down:

Benefits of IMSI:

• Better visualization of sperm (6,000x magnification).

• Improved selection of morphologically normal sperm.

• May lead to better-quality embryos, especially blastocyst embryos (Day 5 embryos).

• Slightly higher fertilization rates in select patients.

Limitations of IMSI:

• Time-consuming (sperm selection can take 15–20 minutes or more).

• Does not guarantee higher pregnancy rates compared to ICSI.

• Requires special equipment and expertise, available only in select referral centers.

• Not necessary for all patients—ICSI works well in the majority of cases.

IMSI can be helpful in specific cases (poor sperm morphology, repeated ICSI failures, embryo arrest).

However, current scientific data show no significant increase in overall pregnancy rates compared to ICSI.

As a referral unit for male infertility and complex IVF cases across India, we use IMSI selectively. We strongly believe in being transparent with patients—not every couple needs IMSI.

At Shree IVF Clinic, we often recommend combining IMSI with genetic testing of embryos (PGT-A). This ensures that the embryos not only look good under the microscope but are also chromosomally normal (euploid)—which is crucial for increasing the chances of a healthy pregnancy.

Being a referral unit for male fertility cases from across India, we feel extremely blessed that many patients—especially those who have faced poor embryo quality in the past or have had poor sperm morphology—come to us for treatment. 

We strongly believe that one reason couples travel from different parts of India to consult us is because our treatment requires them to visit our unit only two times during the entire course of therapy, irrespective of where they live in the country.

In certain cases, we may also use the process of IMSI (Intracytoplasmic Morphologically Selected Sperm Injection) on sperm retrieved through a testicular aspirate. This is usually done for patients with obstructive azoospermia or non-obstructive azoospermia using techniques such as TESE or micro-TESE. 

The aim is to carefully select the best quality sperm from the testicular aspirate so that these patients, too, can achieve pregnancy rates almost at par with other infertility patients.

In real-life practice, IMSI is not offered to every patient undergoing fertility treatment. This is because the value of IMSI lies not just in the software itself but in how it is applied by the clinical team, which makes a big difference to the outcome.

It is also important to understand that IMSI is not a replacement for the standard principles of fertility science. A sound clinical protocol, including proper ovarian stimulation and egg retrieval, remains the backbone of treatment.

The IMSI software itself is very expensive—costing around 25 lakh rupees—and very few clinics in India can afford to invest in it on a large scale. 

However, at Shree IVF Clinic, Mumbai, being a referral unit for male fertility, we make IMSI available to our registered patients as part of their treatment, without any additional charge. 

This ensures that even patients who have already spent a significant amount of money on their fertility journey do not need to worry about extra costs for accessing IMSI at our clinic. 

We hope this detailed explanation helps you gain clarity about the IMSI procedure and supports you in making the right clinical decision for your situation.

At Shree IVF Clinic, Mumbai, under the guidance of Dr. Jay Mehta, we specialize in advanced male infertility treatments, including IMSI and ICSI. If you’ve faced repeated IVF failures or poor sperm quality, book a consultation today at  1800-268-4000 . Let’s work together to give you the best chance at parenthood.

• ICSI is the standard, effective technique for most couples.

• IMSI is an advanced version used in selected cases like poor sperm morphology or repeated IVF/ICSI failures.

• IMSI may improve embryo quality and fertilization, but does not guarantee higher pregnancy rates.

• Best results often come when IMSI is combined with genetic embryo testing.