Immunological Factors in Pregnancy and Infertility

Dr. Friberg has extensive knowledge of immunological factors in infertility. These involve the presence of an anti-sperm immune reaction capable of interfering with fertility variables in one or both partners.

He has a special interest in multiple miscarriages which are also called habitual abortion. They can be caused by endocrine, anatomical and immunological factors as well as infections, and may need an extensive and careful evaluation.

The Role of Antibodies

Antibodies can impact fertility in both men and women:

  • In men, they interfere with sperm function, preventing sperm from penetrating into cervical mucus.
  • In women, the antibodies prevent sperm migration into the uterus and can even immobilize sperm.

In both cases, these antibodies can make it very difficult for sperm to reach and fertilize the egg.

In 1974, Dr. Friberg’s research resulted in creation of the sperm antibody test — now known universally as “The Friberg Test.” As a leading expert in this field, there is no better person to help you and your partner address these difficult issues.

Understanding Sperm Antibodies in Men

Sperm develops and are transported in a special “compartment” that the immune system cannot access. If the integrity of this barrier is broken, sperm can get out into the surrounding tissue, make contact with the immune system, and antibodies can form.

This initiation of sperm antibody production can be seen after infections and severe testicular trauma. It can also occur after surgery that damages the “blood-testis barrier” such as inguinal hernia operations in young boys. However, in some patients we cannot find a cause for the antibody production.

Here is how these antibodies impact fertility:

  • Sperm antibodies circulate in the blood and reenter into the ejaculate through the prostatic secretions (as IgG Ab antibodies) but are also locally produced in the different sperm ducts (as IgA Ab antibodies).
  • These antibodies clump the sperm together (agglutination) and prevent them from entering the cervical mucus.
  • The antibodies are usually not detected in a regular semen exam since these aggregates are dispersed when the ejaculate is handled for analysis. The ejaculate needs to be undisturbed for some time to appreciate the degree of agglutination (clumping).

The Friberg Test

In the “Friberg Test,” the ejaculate is kept in a micro-chamber under liquid paraffin oil for 2 hours, allowing the degree of sperm agglutination to be easily seen.

  • The amount of sperm antibodies can be measured in blood and seminal fluid with a stepwise dilution or titration.
  • Values < 1:64 leave some sperm free to travel to the egg.
  • With titers of 1:128 to 1:256, very few spermatozoa are free to enter the cervical mucus, and the patient can be considered severely oligozoospermic (semen with a low concentration of sperm).
  • At titers above 1:1024, no fertility is usually encountered, and all sperm are clumped together.

Other Sperm Antibody Tests

Sperm antibodies attached to the spermatozoa can be detected with IgA- and IgG-coated small particles. If these antibody coated particles attach to the sperm cell, sperm antibodies are present. If more than 50% of the sperm carry antibody-coated immunobeads or red blood cells (in the MAR test), severe immunological infertility exists.

In the past, multiple treatments have been proposed for sperm antibody production, but most have severe risks for health. We recommend use of in vitro fertilization IVF with intra-cytoplasmic sperm injection (ICSI).

Sperm Antibodies in Women and Infertility

Circulating sperm antibodies in women have not been shown to interfere with fertility. However, locally produced antibodies in the female genital tract can induce long-standing infertility.

The cause of female sperm antibody production is not known, but one theory is that there are bacterial antigens attached to or shared with spermatozoa that the body considers “foreigners.” As a result, a woman may produce an antibody to these bacterial antigens that cross reacts with antigen on the sperm cells and stops their motility.

All female genital tract secretions are difficult to analyze for sperm antibodies because of blood contamination when the fluid is collected and destruction of antibodies when they are prepared from the sticky mucus.

Instead, the best way to observe sperm antibodies in women is to do a post-coital test (PCT) and cross in vitro capillary sperm penetration test using the male partner’s sperm, the female partner’s cervical mucus, donor sperm and donor cervical mucus. If no sperm are detected in the cervical mucus 8 hours after intercourse and the husband and donor sperm do not penetrate the capillary tube with the wife’s cervical mucus but function well in the donor mucus, the presence of local sperm antibodies is likely.

Female sperm antibodies are usually active to all sperm samples, but exceptions have occasionally been seen.