TORCH Infections in Pregnancy
TORCH infections (toxoplasmosis, other, rubella, cytomegalovirus, herpes simplex) cause stillbirth, growth restriction, brain and eye damage, and deafness. This guide covers diagnosis, timing of tests, treatment, delivery, newborn care, and prevention, using the TORCHES approach.
ЁЯОп AT A GLANCE — TORCH INFECTIONS
TORCH stands for Toxoplasmosis, Other infections (syphilis, varicella, parvovirus B19, Zika, listeria, HIV, hepatitis B), Rubella, Cytomegalovirus (CMV), and Herpes simplex virus (HSV)
Shared fetal picture: growth restriction, microcephaly, intracranial calcification, hepatosplenomegaly, jaundice, petechiae, chorioretinitis, and deafness
Maternal illness is often mild or silent; the damage depends on the infection, the gestation at infection, and whether the baby is infected
Do not send a routine 'TORCH panel': test for a reason — exposure, symptoms, or an abnormal scan — and interpret IgM with avidity and PCR (polymerase chain reaction)
Prevention beats treatment: rubella immunity before pregnancy, hygiene and food safety, and screening for syphilis, HIV and hepatitis B in every pregnancy
ЁЯЪи ACT AT ONCE
Abnormal fetal scan — microcephaly, ventriculomegaly, periventricular calcification, hydrops, echogenic bowel, growth restriction, or abnormal liquor: test the mother and refer to fetal medicine Non-immune woman exposed to chickenpox: varicella zoster immunoglobulin or acyclovir within days; chickenpox with breathlessness: intravenous acyclovir and admit Genital herpes lesions or tingling in labour: caesarean section is advised; baby needs herpes evaluation Rash with fever in a pregnant woman: rubella, parvovirus, measles, varicella, Zika — test and avoid contact with other pregnant women ЁЯЧ║️ THE PATHWAY AT A GLANCE
1 · SuspectExposure, symptoms, or a scan finding; note the gestation and date of exposure
2 · TestIgG, IgM, and IgG avidity; paired samples 2–3 weeks apart for rubella or parvovirus
3 · ConfirmAmniotic fluid PCR, 4–8 weeks after maternal infection
4 · TreatSpecific drug or immunoglobulin if available; counsel on the outcome
5 · WatchSerial growth, brain, and Doppler scans; plan delivery and neonatal care
6 · PreventVaccinate, hygiene, safe food; suppress herpes from 36 weeks
STEP 1 · TOXOPLASMOSIS, RUBELLA, CMV — the classic three
ЁЯРИ TOXOPLASMOSIS
| Topic | Details |
|---|
| Source | Undercooked meat, cat faeces, soil, and unwashed vegetables; primary infection in pregnancy only matters (earlier infection protects) |
| Mother | Usually silent; neck lymph nodes, fatigue, or low fever |
| Fetal risk | Transmission rises with gestation (about 15% at 13 weeks, 45% at 26, over 70% near term); damage is worst when infection is early |
| Fetal damage | Hydrocephalus, scattered intracranial calcification, chorioretinitis, seizures, stillbirth; many babies look normal and develop eye disease later |
| Diagnosis | IgG and IgM; high IgG avidity in early pregnancy excludes recent infection; amniotic fluid PCR from 18 weeks and at least 4 weeks after infection |
| Treatment | Spiramycin 1 g three times daily from diagnosis to reduce transmission; if the fetus is infected (after the first trimester): pyrimethamine + sulfadiazine + folinic acid under specialist care |
| Prevention | Cook meat thoroughly, wash vegetables and hands, wear gloves for gardening, avoid cat litter, no raw or cured meat |
ЁЯФ┤ RUBELLA (GERMAN MEASLES)
| Topic | Details |
|---|
| Mother | Mild fever, rash behind the ears, joint pain, lymph nodes; up to half are silent |
| Fetal risk | First 12 weeks: up to 80–90% infected with severe defects; 13–16 weeks: fewer, mainly deafness; after 20 weeks: rare |
| Congenital rubella syndrome (CRS) | Cataract, sensorineural deafness, heart defects (patent ductus arteriosus, pulmonary stenosis), microcephaly, growth restriction, 'blueberry muffin' rash, hepatosplenomegaly |
| Diagnosis | IgM, IgG seroconversion, avidity; PCR on throat or amniotic fluid; immune if IgG is 10 IU/mL or more |
| Treatment | None specific; immunoglobulin is not recommended; counsel early: infection before 16 weeks carries a high risk of defects, and termination is a legal option |
| Prevention | Measles–rubella (MR) vaccine before pregnancy; avoid pregnancy for 4 weeks after it; live vaccine is not given in pregnancy (accidental vaccination is not an indication for termination); vaccinate non-immune women after delivery |
India (national immunisation schedule): MR vaccine at 9–12 months and 16–24 months (up to 5 years if missed); adolescent girls and women of reproductive age without immunity should be vaccinated before pregnancy
ЁЯзл CYTOMEGALOVIRUS (CMV)
| Topic | Details |
|---|
| Importance | Commonest congenital infection (about 0.5–1% of births); most mothers are silent; spread by saliva, urine, and toys of young children |
| Fetal risk | Primary infection: about 30–40% transmission (higher later in pregnancy), but worse damage when early; non-primary (reactivation or reinfection): lower risk |
| Newborn | About 10–15% symptomatic (microcephaly, calcification, jaundice, petechiae, hepatosplenomegaly); 10–15% of silent infections develop sensorineural hearing loss |
| Diagnosis | IgG, IgM, and low avidity in recent infection; amniotic fluid PCR from 21 weeks and at least 6–8 weeks after infection; detailed scan and fetal MRI |
| Treatment | Valacyclovir 8 g daily early in primary infection may reduce transmission (off-label); hyperimmune globulin has not been shown to help; specialist care |
| Newborn | CMV PCR on urine or saliva within 3 weeks of birth; valganciclovir for symptomatic infants; hearing and eye follow-up |
| Prevention | Wash hands after nappy changes and wiping noses; do not share food, cups, or utensils with toddlers; do not kiss on the mouth |
STEP 2 · HERPES, VARICELLA, PARVOVIRUS — viral infections with a clear action
ЁЯФе HERPES SIMPLEX VIRUS (HSV)
| Topic | Details |
|---|
| Risk to the baby | Mainly at delivery: first episode near term: 30–50%; recurrent lesions: under 3%; neonatal herpes: skin, eye and mouth, brain, or disseminated |
| First episode in pregnancy | Acyclovir 400 mg three times daily for 5–10 days (or valacyclovir 500 mg twice daily); take a swab and counsel |
| Suppression | Acyclovir 400 mg three times daily (or valacyclovir 500 mg twice daily) from 36 weeks to delivery for a history of genital herpes or a first episode in pregnancy |
| Delivery | Lesions or prodromal symptoms in labour, or a first episode within 6 weeks of delivery: caesarean section; avoid scalp electrodes and instrumental delivery |
| Newborn | Swabs and bloods if the mother has recent infection or lesions; intravenous acyclovir for suspected or proven neonatal herpes (14–21 days) |
| Breastfeeding | Safe unless there is a lesion on the breast; hand hygiene |
ЁЯЯа VARICELLA (CHICKENPOX)
| Topic | Details |
|---|
| Mother | Pneumonia in 10–20%, the main cause of maternal death; smokers and later gestation are at higher risk |
| Fetus | Congenital varicella syndrome (limb hypoplasia, skin scars, microcephaly, eye damage): about 0.4% before 13 weeks, 2% at 13–20 weeks; neonatal varicella if the mother's rash begins 5 days before to 2 days after delivery |
| Non-immune woman exposed | Varicella zoster immunoglobulin (VZIG) as soon as possible (best within 4 days, up to 10); or acyclovir days 7–14 after exposure |
| Chickenpox in pregnancy | Oral acyclovir 800 mg five times daily for 7 days if seen within 24 hours of the rash and from 20 weeks; intravenous acyclovir 10 mg/kg every 8 hours for pneumonia or severe disease |
| At delivery | Delay delivery to at least 7 days after the rash starts when possible; baby gets VZIG if the rash is within 5 days before or 2 days after delivery |
| Prevention | Live vaccine is not given in pregnancy: vaccinate non-immune women before pregnancy or after delivery, and avoid pregnancy for 4 weeks |
ЁЯФ╡ PARVOVIRUS B19 (FIFTH DISEASE)
| Topic | Details |
|---|
| Mother | Slapped-cheek rash, joint pain, or no symptoms; mild |
| Fetus | Red cell aplasia: anaemia, hydrops; loss in 5–10% (highest at 9–20 weeks); no malformations |
| Diagnosis | IgM and IgG, PCR; if infected, then fetal surveillance |
| Surveillance | Middle cerebral artery peak velocity (Doppler) and scan for hydrops every 1–2 weeks for 8–12 weeks; raised velocity (above 1.5 multiples of the median) means fetal anaemia |
| Treatment | Intrauterine blood transfusion for severe anaemia or hydrops (in a fetal medicine centre); good outcome after recovery |
| Prevention | Hand hygiene; no vaccine; exclusion from work is not required |
STEP 3 · 'OTHER' INFECTIONS AND THE NEWBORN — screen, treat, and examine
ЁЯзм OTHER CONGENITAL INFECTIONS
| Infection | Key points |
|---|
| Syphilis | Screen every pregnant woman at the first visit; benzathine penicillin G; treat partner; see the dedicated sheet on reactive VDRL (Venereal Disease Research Laboratory test) |
| HIV | Test every pregnant woman; lifelong antiretroviral therapy and infant prophylaxis; see the dedicated sheet |
| Hepatitis B | Hepatitis B surface antigen (HBsAg) screening in pregnancy; vaccine at birth, within 24 hours (national schedule) and immunoglobulin for babies of HBsAg-positive mothers; tenofovir in late pregnancy for a high viral load |
| Zika virus | Mosquito-borne; microcephaly and brain damage; PCR in blood and urine; no treatment; avoid affected areas and use repellents and nets |
| Listeria | Unpasteurised dairy, soft cheese, deli and ready-to-eat foods; febrile illness, stillbirth, neonatal sepsis; blood cultures, amoxicillin or ampicillin |
| Others | Enteroviruses, lymphocytic choriomeningitis virus, malaria (see the dedicated sheet), Chagas disease |
ЁЯС╢ THE NEWBORN WITH A SUSPECTED CONGENITAL INFECTION
Look for: small for dates, microcephaly, jaundice, petechiae or purpura, hepatosplenomegaly, cataract or white pupil, heart murmur, and failed hearing screen
Tests: blood count and platelets, liver tests, CMV PCR on urine or saliva, cranial ultrasound, eye and hearing examination, and pathogen-specific tests (IgM, PCR)
Placenta: send for histology and PCR
Treat according to the infection: valganciclovir (CMV), acyclovir (HSV), penicillin (syphilis), pyrimethamine and sulfadiazine for up to 12 months (toxoplasmosis)
Follow-up: hearing, vision, growth, and neurodevelopment; counsel the parents on recurrence risk and prevention in the next pregnancy
⚠️ COMMON PITFALLS
Ordering a TORCH panel for every miscarriage or small baby without a clinical reason
Treating a single positive IgM as proof of recent infection — IgM can persist or be false positive; check avidity and repeat
Amniocentesis too early — PCR is falsely negative if done before the right interval after maternal infection
Giving a live vaccine (rubella, varicella) in pregnancy, or advising pregnancy within 4 weeks of it
Missing herpes lesions or prodrome at admission in labour, or forgetting 36-week suppression
Forgetting the newborn: hearing screen, eye examination, and CMV test
Seven rules for congenital infections.
T
Toxoplasma — spiramycin early, PCR on amniotic fluid, cook meat and wash hands
O
Other — syphilis, HIV, hepatitis B screened in all; varicella and parvovirus have set plans
R
Rubella — vaccinate before pregnancy, never during; no treatment once infected
C
CMV — hygiene, PCR at 21 weeks or later, hearing follow-up
H
Herpes — suppress from 36 weeks, caesarean for lesions or prodrome
E
Evaluate the newborn — scan, hearing, eyes, urine CMV PCR
S
Serial scans — growth, brain and Doppler; test for a reason, not by panel
Remember: prevent, test for a reason, time the test, treat what can be treated, and examine the baby.
