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Maternal-Fetal Medicine

Immunology at the Maternal-Fetal Interface

The maternal-fetal interface is a unique immunological environment that balances fetal tolerance with immune protection and protects both the mother and fetus from infections while preventing the immune rejection of the genetically distinct fetus. This specialized interface, centered around the placenta and involving the decidua, facilitates close interaction between maternal and fetal immune systems. This ensures proper embryonic development while defending against infections, thereby serving a

v1 · Reviewed Nov 7, 2026 by Automated Clinical Reviewer (Strict Verbatim v1)
  • Trophoblast invasion can also occur in organs outside the uterus, such as the fallopian tubes, leading to an ectopic pregnancy.
  • An infective or noninfective insult at the placental level, triggering the secretion of pro-inflammatory cytokines such as IL-6, IL-12, and tumor necrosis factor-alpha (TNF-α), can lead to placental damage and result in complications such as preterm labor, abortion, or preeclampsia.
  • Placental abruption is associated with sterile inflammatory changes resulting from inadequate decidual suppressive activity and elevated levels of cytotoxic immune cells in the decidua.
  • Triggers such as infection, stress, or inflammation during pregnancy can prematurely shift the maternal immune state from anti-inflammatory to pro-inflammatory, triggering preterm labor.
  • Disruptions in immune tolerance at the maternal-fetal interface can lead to complications, including preeclampsia, recurrent pregnancy loss, and infertility.
  • Viral infections during pregnancy can significantly increase the risk of miscarriage, preterm birth, low birth weight, and fetal neurological impairments.
  • In patients with unexplained infertility, endometrial biopsies have revealed significantly fewer NK cells than in fertile individuals.
  • Preeclamptic pregnant women exhibit elevated pro-inflammatory cytokines (TNF-α, IL-6, and IL-8) and reduced anti-inflammatory cytokines (IL-10).
  • RSA patients exhibit increased mature dendritic cells and decreased immature dendritic cells.
  • Neutrophil levels are elevated in the decidua of pregnant women with preterm labor and chorioamnionitis.
  • TORCH infections, which include toxoplasmosis, other infections (such as varicella, syphilis, parvovirus B19, Zika virus, and HIV), rubella, Cytomegalovirus , and herpes simplex virus.
  • Intravenous immunoglobulin and allogenic lymphocyte immunotherapy increased the successful pregnancy rate among RSA patients of unknown etiology pursuing in-vitro fertilization.
  • Cyclosporine A has also been used to enhance Treg cells in RSA patients.
  • Progesterone has been shown to reduce the risk of miscarriage in patients with RSA.
Intravenous immunoglobulin
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Adult
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Renal
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Duration
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Cyclosporine A
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Adult
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Renal
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Duration
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Progesterone
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Adult
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Renal
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Duration
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  • Treg-enhancing drugs, adoptive Treg cell therapy, and low-dose IL are currently being tested for RSA treatment.
  • Biologic agents, such as eculizumab, a monoclonal antibody targeting complement protein C5, offer promise for managing immune dysfunction in conditions such as preeclampsia and HELLP syndrome.
  • Impaired development of the maternal-fetal interface may result in implantation failure, infertility, recurrent miscarriage, or intrauterine growth restriction (IUGR).
  • The trophoblast invasion is superficial in preeclampsia when compared to unaffected pregnancies.
  • In patients with unexplained infertility, endometrial biopsies have revealed significantly fewer NK cells than in fertile individuals.
  • Additionally, infertility and recurrent spontaneous abortions (RSAs) are indirectly correlated with impaired Treg cell function.
  • Preeclamptic pregnant women exhibit elevated pro-inflammatory cytokines (TNF-α, IL-6, and IL-8) and reduced anti-inflammatory cytokines (IL-10).
  • Increased inflammatory response to semi-allogeneic fetal antigens leads to impaired spiral artery remodeling, shallow trophoblast invasion, and placental infarction, predisposing to preeclampsia.
  • Placental abruption is associated with sterile inflammatory changes resulting from inadequate decidual suppressive activity and elevated levels of cytotoxic immune cells in the decidua.
  • Advanced maternal age can disrupt the T-cell profile at the maternal-fetal interface, potentially leading to reduced fetal survival or IUGR.
  • review
    Immunology at the Maternal-Fetal Interface. StatPearls [Internet] — Palanikumar Balasundaram, Aisha Farhana — StatPearls Publishing, 2025

Decision support only. Verify against local protocols and current labeling. Source: www.ncbi.nlm.nih.gov