Routine HSV Screening in Pregnancy is NOT Recommended
Pregnant women should NOT be routinely tested for HSV with type-specific serologies during pregnancy 1. This recommendation is based on current guidelines from the American College of Obstetrics and Gynecology, which advise against universal screening due to lack of evidence for cost-effectiveness 1.
When HSV Testing IS Indicated During Pregnancy
While routine screening is not recommended, targeted testing is appropriate in specific clinical scenarios:
1. Active Genital Lesions During Pregnancy
- If a pregnant woman presents with genital lesions and has no prior history of genital herpes, perform PCR testing of the lesion AND HSV type-specific IgG serology 2
- This combination distinguishes between:
- True primary infection (highest risk for neonatal transmission)
- Non-primary first episode (moderate risk)
- Recurrent infection (lowest risk)
- This testing influenced clinical management in 79% of pregnant patients in one recent study 3
2. Known HSV History - Determining Dual Infection
- If a pregnant woman has known genital HSV but you need to determine whether she has antibodies to both HSV-1 and HSV-2, type-specific serology is indicated 1, 3
- This impacted management in 96% of cases 3
3. Serodiscordant Couples
- Testing to identify serodiscordance with partners during pregnancy is appropriate 3
- This influenced management in 100% of tested couples 3
4. What NOT to Do
- Do NOT perform genital sampling or serology in pregnant women with a history of genital herpes who have no active lesions 2
- Do NOT order HSV IgM testing - it is useless for diagnosis 2
- Do NOT perform PCR testing of amniotic fluid routinely (0% detection rate in 4,383 tests) 4
The Epidemiologic Context
Recent meta-analysis data shows that HSV-1 IgG seroprevalence is 79.1% and HSV-2 IgG is 28.6% among pregnant women globally 4. However, acute infection markers (IgM) are uncommon: only 1.9% for HSV-1 and 4.7% for HSV-2 4. This high IgG seroprevalence reflects widespread prior exposure and protective maternal immunity rather than active infection risk, further supporting the recommendation against universal screening 4.
Management Focus Instead of Screening
Rather than screening, management should focus on:
- Taking a careful history of genital herpes in all pregnant women 1
- Suppressive antiviral therapy starting at 36 weeks for women with known recurrent genital herpes (acyclovir 400mg TID or valacyclovir 500mg BID) to reduce viral shedding, recurrences, and cesarean deliveries 1
- Clinical assessment at delivery for active lesions
- Recognizing and treating primary infection during pregnancy when it occurs
Important Caveat on Antiviral Safety
One case-control study showed a 4.7-fold increased odds of gastroschisis among women using antiherpes medications between one month before conception and the third month of pregnancy 1. However, this finding had significant limitations including demographic differences and possible recall bias, and acyclovir remains pregnancy category B 1. The established benefits of suppressive therapy from 36 weeks onward are well-documented 1.