TORCH Framework

TORCH Screening Framework

Indications & Diagnostic Rationales

Toxoplasmosis

Other (Syphilis)

Rubella

CMV

HSV

Diagnostic Triggers

Maternal Exposure

Known contact with primary infection (especially Rubella/VZV).

Ultrasound Markers

Intracranial calcifications, Hydrops, Organomegaly, Microcephaly.

Seroconversion

Rising IgG or presence of IgM with low Avidity.

Fetal Growth

Severe early-onset Fetal Growth Restriction (<20 weeks).

Clinical Ref: Routine "Panel" testing is discouraged by FIGO/RCOG due to high false-positive rates. Testing should be serial and pathogen-specific based on clinical suspicion.

Guidelines & Evidence

Verified

Last Review: 2026-07-17

When to Use

Differential diagnosis for symmetric Intrauterine Growth Restriction (IUGR).

Evaluation of fetal anomalies on ultrasound (e.g., intracranial calcifications, microcephaly, hydrops).

Screening pregnant patients with concerning exposures or viral prodromes (fever, lymphadenopathy, rash).

Workup for unexplained stillbirth or neonatal jaundice/thrombocytopenia.

Exclusion Criteria

The TORCH framework is a screening heuristic. It is not a single "test" but a diagnostic approach. Routine universal TORCH screening in asymptomatic patients is not cost-effective and is generally discouraged by ACOG.

How it Works

The Acronym Breakdown

T	Toxoplasmosis (T. gondii)
O	Other (Syphilis, Parvovirus B19, VZV, Zika, HIV)
R	Rubella
C	Cytomegalovirus (CMV)
H	Herpes Simplex Virus (HSV)

Pathophysiology

These agents share the ability to cross the placenta (hematogenous spread) or infect the fetus via the birth canal (ascending/contact spread). The severity of fetal impact is generally inversely proportional to the gestational age at the time of primary maternal infection.

Clinical Pearls

Diagnostic Pearls

CMV: The most common congenital infection; look for periventricular calcifications on US.

Toxoplasmosis: Classically presents with the triad of chorioretinitis, hydrocephalus, and intracranial calcifications (diffuse, unlike CMV).

Syphilis: Rising incidence; check RPR/VDRL at first visit and again at 28 weeks in high-risk areas.

HSV: Risk of transmission is highest (30–50%) during a primary outbreak at the time of delivery; recurrent outbreaks carry <1% risk.

Serology Pitfalls

IgM false positives are common; always confirm with IgG avidity testing if available.

Low IgG avidity suggests a primary infection within the last 3–4 months.

Do not wait for seroconversion in HSV; if lesions are present, treat empirically and consider C-section.

Common US Findings

Intracranial Calcifications	CMV (Periventricular) or Toxoplasmosis (Diffuse)
Hydrops Fetalis	Parvovirus B19, Syphilis, CMV
Limb Hypoplasia	Varicella (VZV)
Hepatomegaly	Syphilis, CMV

Last Comprehensive Review: 2026-07-17

Recent Journal Updates

British J HaematologyJul 21, 2026

Optimizing post‐transplant tyrosine kinase inhibitor maintenance in Philadelphia chromosome‐positive acute lymphoblastic leukaemia: A risk‐adapted framework

Clinical Context

We think this might be relevant to the clinical guidance for TORCH Framework — Perinatal Infections.

WHO NewsJul 18, 2026

WHO Member States continue negotiations on the Pathogen Access and Benefit Sharing Annex

Clinical Context

We think this might be relevant to the clinical guidance for TORCH Framework — Perinatal Infections.

Emerging Infectious DiseasesJul 16, 2026

Antimicrobial Resistance in Extragenital Neisseria gonorrhoeae Infections, US Military Centers, 2022–2024

Clinical Context

We think this might be relevant to the clinical guidance for TORCH Framework — Perinatal Infections.

TORCH Framework

TORCH Screening Framework

When to Use

When to Use

Exclusion Criteria

How it Works

The Acronym Breakdown

Pathophysiology

Clinical Pearls

Diagnostic Pearls

Serology Pitfalls

Common US Findings

Next Steps

Next Steps for Positive Maternal Serology

Delivery Considerations

The Evidence

Key Citations

Practice Bulletin No. 151: Cytomegalovirus, Parvovirus B19, Varicella Zoster, and Toxoplasmosis in Pregnancy.

Congenital cytomegalovirus infection: antenatal and postnatal considerations.

Origins & History

History of the Acronym

Recent Journal Updates

TORCH Framework

TORCH Screening Framework

When to Use

When to Use

Exclusion Criteria

How it Works

The Acronym Breakdown

Pathophysiology

Clinical Pearls

Diagnostic Pearls

Serology Pitfalls

Common US Findings

Next Steps

Next Steps for Positive Maternal Serology

Delivery Considerations

The Evidence

Key Citations

Practice Bulletin No. 151: Cytomegalovirus, Parvovirus B19, Varicella Zoster, and Toxoplasmosis in Pregnancy.

Congenital cytomegalovirus infection: antenatal and postnatal considerations.

Origins & History

History of the Acronym

Recent Journal Updates