IVF & ICSI: Everything You Need to Know About How These Procedures Work Together

People come from all over the world to be treated at the Arizona Center for Reproductive Endocrinology & Infertility. We’ve pioneered many different techniques and procedures to help our patients get pregnant. About 20 years ago, we received grant money that allowed us to pioneer the ICSI technique. In conjunction with IVF, it’s helped us achieve pregnancies for couples who had previously been unable to conceive together.

What Is IVF?

In vitro fertilization (IVF) is a procedure in which we retrieve all the eggs a woman naturally produces during any given month. The eggs are then paired with several hundred thousand sperm and fertilized in a petri dish in the laboratory. After fertilization, we can monitor the developing health of the embryos to make sure they’re chromosomally competent (and not likely to miscarry). Once the embryos are developed, we re-insert them back into the woman’s uterus and then follow up with the patient in two weeks to determine if she is pregnant.

What Is ICSI?

ICSI, or intra-cytoplasmic sperm injection, is also known as assisted fertilization. With this method, we are able to take a single sperm and, under a microscope, inject it through an egg’s zona pellucida to achieve fertilization.

To understand how this works, you have to understand fertilization. The egg is surrounded by a glycol-protein covering called the zona pellucida; sperm have little packets of enzymes on their heads that help dissolve the zona enough to actually penetrate the egg and cause fertilization. One sperm, or a small amount of sperm will not carry enough enzymes for the zona to dissolve and fertilization to occur. With the ICSI technique, we are able to bypass the zona pellucida and inject the sperm directly into the egg.


ICSI must be done in conjunction with in vitro. We retrieve the eggs during the in vitro process and can then fertilize them with ICSI. Using both the procedures, we are able to achieve a fairly high pregnancy rate, and the embryo will continue to develop normally.

Who Can ICSI and IVF Help?

Men with Low Sperm Counts

When men have a sperm count so low it can’t be overcome by medical treatments or by fertility treatments (like intra-uterine insemination), we can use assisted fertilization. The advantage is that we only have to use one sperm, so even if a man has a very low sperm count, it’s typically still more than enough to fertilize the egg.

Couples Experiencing Idiopathic Infertility

We can often overcome idiopathic, or unexplained, infertility by using the ICSI technique. For example, with some couples, the reason for their infertility isn’t clear, and when we put the egg and sperm together in the petri dish, fertilization doesn’t occur. When we see that fertilization does not occur naturally, we can then use the ICSI technique to help the sperm fertilize the egg. Then once the egg is fertilized and the embryo develops, we transfer the embryo back into the uterus. The couple now has a very good chance at pregnancy because we solved the problem of failed fertilization.

Men with No Sperm in Their Semen

Some men are diagnosed with no sperm in their semen, and occasionally that is due to what we call obstructive azoospermia—a blockage in the ducts that carry the sperm prevent the sperm that’s produced in the testes from reaching the seminal fluid at the time of ejaculation. For example, cystic fibrosis is associated with congenital absence of the vas deferens; men with this disorder have sperm in their testes but not in their semen. We can overcome this through a simple in-office procedure called testicular sperm extraction (TESE). We typically perform the TESE with a urologist and perform a biopsy to obtain sperm from the testes. When we do this procedure, we usually obtain 100 to a few thousand sperm—not enough to achieve fertilization through regular in vitro, but more than enough to fertilize the egg with the ICSI technique and IVF.

Men Having a Vasectomy

Before a man has a vasectomy, the physician will offer to freeze a vial of sperm, in case they want to have kids in the future. In the past, a single vial wouldn’t be enough to achieve a pregnancy through artificial insemination. With that one vial of sperm we could perform the ICSI technique and that man would be able to have many more children.

ICSI and IVF are both highly technical procedures, but they offer an extremely high chance of fertilization. And once the egg is fertilized, the embryo should develop normally, and the couple will have a healthy, happy baby at the end of nine months. To make an appointment and learn more about how IVF and ICSI can help you achieve a pregnancy, visit Arizona Center for Reproductive Endocrinology & Infertility online or call us at 520-326-0001.