Immune therapy refers to the treatment of immunological dysfunction that affects implantation and pregnancy outcome. The most common immunologic treatment options include steroid therapy before implantation and during the early stages of pregnancy, blood thinners and baby aspirin, intravenous immunoglobulin (IVIG) and more recently Intralipid therapy.
Corticosteroid Therapy (Prednisone, Prednisolone or Dexamethasone)
Steroid therapy has become routine practice in most IVF programs and they are believed to act by inhibiting the cellular immune response. We prescribe oral dexamethasone within ten days of initiating ovarian stimulation with gonadotropins, and continuing until the diagnosis of pregnancy, whereupon, in the event of a negative test, the dosage is tapered over a period of seven to ten days, and then discontinued. Pregnant patients continue treatment throughout the first trimester up to 7-8 weeks of gestation.
Heparin and Baby Aspirin
In cases of recurrent pregnancy loss, current evidence suggests improvement in pregnancy outcome with the use of blood thinners (heparin) and baby aspirin in patients with anti-phospholipid syndrome (a thrombophiliac disorder). It is common practice to administer this regimen in the presence of other thrombophilias, despite lack of strong medical evidence. Typically, the regimen is started with the first positive pregnancy test and continued until the end of the first trimester. In some cases, treatment is continued throughout pregnancy and the postpartum period.
Intravenous Immunoglobulin (IVIG)
IVIG is a concentrated immunoglobulin G (IgG) solution derived from human plasma. It is believed to modulate immunologic function at the time of implantation. It suppresses activated Natural Killer cells (NKa), reduces the activity of T-cells, suppresses B cells to prevent the production of antibodies and opposes other toxic antigens.
It is recommended to administer IVIG at least 7 days prior to embryo transfer and once again when pregnant. The selective use of immunotherapy can result in successful pregnancies in patients who had previously suffered repeated IVF failures.
Intralipid is a solution commonly used for parenteral nutrition. More recently Intralipid has been shown to suppress NKa in culture systems, and is proposed to improve pregnancy outcome. Its use is limited to cases with a history of activated NK cells and poor reproductive outcome.