Introduction to Paternal Lymphocyte Immunization Therapy (PLI / LIT)

If you’ve been through the heartbreak of losing a pregnancy more than once, you’re not alone. Many couples struggling with recurrent miscarriages often find that the cause remains unclear. In some cases, it isn’t a problem with the embryo or uterus, but rather with how the mother’s immune system responds to the pregnancy. This condition is known as pregnancy loss due to immune system imbalance, and it can deeply affect your journey to parenthood.


Lymphocyte Immunization Therapy (LIT), also known as Paternal Lymphocyte Immunization (PLI), is a treatment that may offer hope. It helps prepare the mother’s immune system for pregnancy by creating tolerance toward the paternal cells carried by the fetus. Simply put, it helps your body recognize the baby as part of you and not as a foreign invader. While not yet a universally accepted treatment, LIT is considered an option in selected cases, particularly when all other causes of recurrent loss have been ruled out.

Xenith Hope Circle

Join our new WhatsApp community

Are you facing fertility issues or undergoing IVF treatment? You’re not alone in this journey; we’re here to provide support.
* All identities remain anonymous, ensuring a safe and confidential space.

When is Lymphocyte Immunization Therapy Recommended?

Lymphocyte Immunization Therapy may be right for you if:

  • You have experienced multiple miscarriages (usually three or more).
  • You’ve had repeated IVF failures, even when the embryo quality was good.
  • You’ve been diagnosed with unexplained infertility, and other common causes have been ruled out.

In such cases, doctors may consider the possibility that your immune system is reacting negatively to the pregnancy. LIT helps by teaching your body to accept the paternal genetic material from the embryo, promoting a more supportive environment for implantation and growth.

Not all fertility clinics offer LIT.

For couples facing challenges in their fertility journey, LIT can bring renewed hope. Some of the key benefits include:

  • Improved embryo implantation rates
    By reducing immune rejection, LIT helps the embryo successfully attach to the uterus.
  • Reduced chances of miscarriage
    When your immune system is more accepting, it’s less likely to attack the developing embryo, helping sustain the pregnancy.
  • Strengthened maternal immune tolerance
    The therapy helps the mother’s immune system become familiar with the father’s genetic markers, preparing your body for a healthy pregnancy.

In essence, LIT works like a “training session” for your immune system. It introduces your body to your partner’s lymphocytes (a type of white blood cell) in a controlled way, encouraging your immune system to respond positively rather than defensively.

One of the comforting things about Lymphocyte Immunization Therapy is that side effects are usually minimal.
You may experience:

  • Mild redness or swelling at the injection site
  • Temporary discomfort, similar to a routine vaccination

An Allergic reaction testing is done prior in many clinics to ensure compatibility. Serious complications are rare, especially when the procedure is done by experienced professionals. Your medical team will screen both partners carefully before the procedure to ensure safety. If you have concerns, always feel free to ask your doctor—they are there to help guide you through every step.

The process of Lymphocyte Immunization is fairly straightforward and generally well tolerated. Here’s what you can expect:

  1. Blood is collected from the male partner (the biological father).
  2. The lymphocytes (white blood cells) are separated from the rest of the blood.
  3. These lymphocytes are injected into the skin of the mother’s forearm in small doses.
  4. Over time, this exposure helps the mother’s immune system recognize and accept the paternal cells.
  5. The treatment may be repeated depending on your doctor’s recommendations often before conception and again during early pregnancy.

This step-by-step method is designed to gently “educate” your immune system and prepare it to welcome a future pregnancy.

In many protocols, LIT is done twice before pregnancy and repeated once or twice in early pregnancy though protocols vary by clinic. In some clinics, donor lymphocytes (from an HLA-compatible third party) are used when partner’s lymphocytes aren’t viable.

The cost can vary by clinic and region but usually ranges between $300 to $1000 per session. Your doctor can give you a clearer estimate based on your treatment plan.

LIT Therapy is a process where the mother is injected with the father’s white blood cells to help her immune system accept and support the pregnancy.

Side effects are usually mild and may include redness or swelling at the injection site. Serious reactions are rare when done under professional care.

Choosing the right fertility clinic is essential for the success of oocyte freezing by vitrification. Our clinic offers:

  • Experienced fertility specialists with a proven track record of high success rates in egg freezing and IVF.
  • State-of-the-art laboratory technology ensuring optimal conditions for egg preservation.
  • Transparent pricing & flexible payment plans, making egg freezing accessible to more women.
  • Best clinic for oocyte freezing by vitrification – Our expertise in vitrification technology ensures the highest survival rates for frozen eggs.
  • Best clinic for egg freezing – Recognized for outstanding patient care and cutting-edge fertility treatments.
  • Is egg freezing safe? Yes, the vitrification method has been extensively researched and is considered a safe and effective fertility preservation method.
  • Book egg freezing consultation – Contact us today to discuss your options and begin your fertility journey.

Egg freezing empowers women with reproductive choices and provides a sense of security for their future family-building plans. If you are considering egg freezing, consult with our experts to explore the best options tailored to your fertility goals.

We understand that fertility preservation is a deeply personal choice. Our team ensures each woman feels informed, supported, and empowered.

If you’re navigating the difficult path of repeated pregnancy loss, you’re not alone. Treatments like Lymphocyte Immunization Therapy are helping many couples find hope and success in their fertility journeys.

Why Choose Xenith?

We have years of experience, expertise and the latest reproductive technologies in the area of infertility and treatment plan designed for individual needs. The staff at Xenith is highly trained in the latest embryological, medical and technological know-how as well as counselling and therapeutic communication. We are equipped to offer evidence-based treatment in infertility efficiently.

Book Appointment Today!

    Recent Posts

    Book Appointment