Are TORCH (Toxoplasmosis, Other, Rubella, Cytomegalovirus, and Herpes) panels useful at 25 weeks in cases of Intrauterine Growth Restriction (IUGR)?

From the Guidelines

TORCH panels are not useful at 25 weeks in cases of Intrauterine Growth Restriction (IUGR).

Key Points

• The Society for Maternal-Fetal Medicine recommends against screening for toxoplasmosis, rubella, or herpes in pregnancies with FGR in the absence of other risk factors 1.
• The use of polymerase chain reaction for cytomegalovirus (CMV) is recommended in women with unexplained FGR who elect diagnostic testing with amniocentesis 1.
• The diagnosis and management of FGR should be based on early diagnosis, optimal fetal surveillance, and timely delivery that reduces perinatal mortality and minimizes short- and long-term morbidity 1.
• The decision to deliver is typically guided by maternal factors, such as the presence of maternal hypertension, and by fetal comorbidities, such as the degree of growth restriction and the severity of abnormal fetal surveillance results 1.
• Umbilical artery Doppler assessment is recommended to assess for deterioration in FGR 1.

Rationale

The evidence suggests that TORCH panels are not useful in the management of FGR at 25 weeks gestation. The Society for Maternal-Fetal Medicine recommends against screening for toxoplasmosis, rubella, or herpes in pregnancies with FGR in the absence of other risk factors 1. Instead, the focus should be on early diagnosis, optimal fetal surveillance, and timely delivery to reduce perinatal mortality and minimize short- and long-term morbidity 1. The use of umbilical artery Doppler assessment is recommended to assess for deterioration in FGR 1.

Clinical Implications

• Clinicians should not routinely order TORCH panels in cases of FGR at 25 weeks gestation.
• The diagnosis and management of FGR should be individualized based on fetal and maternal factors.
• Umbilical artery Doppler assessment should be used to monitor fetal well-being in cases of FGR.
• The decision to deliver should be guided by maternal and fetal factors, including the presence of maternal hypertension and the severity of abnormal fetal surveillance results.

From the Research

Usefulness of TORCH Panels at 25 Weeks in Cases of IUGR

• The usefulness of TORCH panels at 25 weeks in cases of Intrauterine Growth Restriction (IUGR) is a topic of debate, with some studies suggesting that routine TORCH screening may not be necessary 2, 3, 4.
• A study published in 2013 found that out of 319 patients with FGR, no cases of maternal or congenital infection with toxoplasma, rubella, or herpes simplex virus were found, and only 1.8% were diagnosed with congenital CMV infection 2.
• Another study published in 2024 found that the diagnostic yield of TORCH screening for obstetrical indications, including IUGR, is unclear, and that routine TORCH screening in pregnancies complicated with IUGR should be avoided 3.
• A 2000 study found that the yield of workup for TORCH infection among infants with IUGR is poor and does not justify the incurred costs 4.
• However, some studies suggest that individual TORCH tests may be useful based on the clinical presentation and history of the patient, and that suggestive maternal symptoms and specific fetal sonographic features should prompt testing for CMV and Toxoplasma infection 5, 3.

Specific Findings

• A 2013 study found that a complete maternal TORCH screening for cases of FGR appears to be unnecessary, although a maternal CMV test can be considered 2.
• A 2024 study found that the rates of positive maternal TORCH screening in IUGR were 2.1%, and that none of the neonates with congenital infection were screened for TORCH during pregnancy due to polyhydramnios, oligohydramnios, or IUGR 3.
• A 2000 study found that none of the infants with IUGR had positive IgM titers for toxoplasma, rubella, CMV, or HSV, and that only one infant had a positive urine culture for CMV 4.

Cost-Effectiveness

• A 2000 study found that the costs associated with workup for TORCH infections among 75 infants with IUGR included $17,816 for TORCH titers determination, $1318 for total IgM titers, $5734 for urine culture for CMV, and $28,165 for head ultrasound 4.
• The study concluded that the yield of workup for TORCH infection among infants with IUGR is poor and does not justify the incurred costs 4.