Australian Herpes Management Forum

Herpes Simplex in Pregnancy

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Compiled by the Board of the Australian Herpes Management Forum

Management of pregnant women with first episode genital herpes

Obtain HSV serology (type specific) + type genital culture and ideally test the serum in parallel with first antenatally collected sample to define the episode as primary or first episode.

First and second trimester acquisition

Management of the woman should be in line with the clinical HSV presentation and may involve the use of either oral or intravenous (IV) aciclovir in standard doses. Providing that delivery does not ensue, and no lesions are evident at delivery the pregnancy should be managed expectantly with vaginal delivery anticipated. Continuous suppressive aciclovir in the last four weeks of pregnancy may be indicated for the patient with multiple clinical recurrences to prevent recurrences at delivery and hence the need for Caesarean section.

 That is:

• Primary HSV at less than 34 weeks with no lesions in labour should be managed by vaginal delivery.
• Primary HSV less than 34 weeks and with lesions in labour and ruptured membranes for less than 6 hours should be managed with Caesarean section.

Third trimester acquisition

Apart from aciclovir treatment Caesarean section should be considered for all women, particularly those developing symptoms with- in 6 weeks of delivery as their infants are most at risk of viral transmission due to the lack of time for development of maternal neutralizing antibodies with consequent passage across the placenta. If vaginal delivery occurs, IV aciclovir treatment of mother and baby are indicated. The neonatal attack rate for those exposed before development of maternal seroconversion is in the order of 30 to 50%.

Management of the neonate

Babies born to mothers with first episode genital herpes at the onset of labour

To allow early identification of infected babies HSV culture and/or polymerase chain reaction (PCR) of surface swabs including oropharynx, eyes, urine and CSF should be performed. In addition EDTA blood for PCR should be taken. Intravenous aciclovir 20mg/kg/tds for 14 days should be commenced and continued for 21 days if the CSF is abnormal. If aciclovir is not started immediately the neonate should be closely monitored for signs of lethargy, fever, poor feeding or lesions. Aciclovir should be commenced immediately should any cultures become positive.

Neonatal Herpes

Neonatal herpes is a very rare, but serious infection with high morbidity and mortality. The incidence in Australia is – 3.9/ 100,000 live births.

Risk of neonatal HSV and delivery mode:

• Recurrent HSV - no lesions and vaginal delivery (shedding risk is in the order of 1.4%) and the risk of neonatal HSV is 0.02 to 3% (non-shedding vs HSV shedding respectively)
• For those with recurrent lesions and vaginal delivery (shedding risk by culture is 20%) and the risk of neonatal HSV is =<1%.
• For primary initial episode with seroconversion prior to delivery (prior to 30-34 weeks) the shedding risk is 7% and neonatal HSV =<3%. Whereas for primary/initial episode less than 6 weeks before delivery the risk of neonatal HSV is 30-50%

Management of pregnant women with recurrent genital herpes

Sequential third trimester cultures to predict viral shedding at term are not indicated.

Caesarean section to prevent neonatal herpes should not be performed in women who do not have genital lesions evident at delivery.

Symptomatic recurrences of genital herpes during the third trimester will be brief and vaginal delivery is appropriate if no lesions are present at delivery. For those with multiple recurrences in pregnancy and in order to avoid a Caesarean section, consider suppressive aciclovir treatment at 400mg tds. Specimens for HSV culture (sweep genital swab) are advised at delivery if the baby is delivered vaginally, in order to identify the babies exposed to women asymptomatically shedding HSV.

Management of women with genital lesions at onset of labour

• Current practice is for delivery by Caesarean section, particularly if the membranes have been ruptured for less than six hours.
• There is evidence that the risks of viral transmission to the neonate following vaginal delivery are small and must be weighed against risks of Caesarean section to the mother

Management of the neonate

Babies born to mothers with recurrent genital herpes at the onset of labour

One set of specimens for viral culture should be collected after delivery for early identification of infection. If cultures are positive, aciclovir treatment of the infant is advised. Parents should be advised to report early signs of infection (lethargy, fever, poor feeding or lesions).

Babies born to asymptomatic mothers with a history of genital herpes

Routine viral culture is not recommended. Parents should be advised to report early signs of infection (lethargy, fever, poor feeding or lesions).

Post-natal care of mother and child

Breastfeeding is recommended unless the mother has lesions around the nipples. Aciclovir is excreted in breast milk but its use is not contra-indicated as it does not cause harm to the infant.

Prevention of acquisition of infection

There is a dearth of evidence on which to formulate guidelines for prevention. Any strategy for prevention of neonatal herpes needs to involve both parents.

All women should be asked at their first antenatal visit if they or their partner have ever had genital herpes.

Women whose partners have a history of genital herpes should be strongly advised not to have sex at the time of lesion recurrence. Type specific serology may help confirm risk of primary infection and identify potential risk of asymptomatic shedding in those women already infected but undiagnosed. Conscientious use of condoms throughout pregnancy may diminish the risk of acquisition.

Pregnant women should be advised of the risk of acquiring genital HSV-1 as a result of oro-genital contact. Identifying susceptible women by means of type-specific antibody testing has been evaluated in Australia with a seroprevalence of HSV 2 of 12.5% and HSV 1 of 80% reported. Whilst 3% acquired HSV 2 during pregnancy, none seroconverted to HSV 1 and no cases of neonatal HSV were seen. Therefore it was concluded in low prevalence communities, it is not cost effective to offer type specific serology to pregnant women and their partners.

All women, not just those with a history of genital herpes, should undergo careful vulval inspection at the onset of labour to look for clinical signs of herpes infection. Foetal scalp electrode, forceps and vacuum delivery should be avoided.

Mothers, staff and other relatives/friends with active oral lesions should be advised about the risk of post-natal transmission.

Bibliography

1. Arvin A, Hensleigh PA, Prober CC, et al. Failure of antepartum maternal cultures to predict the infants risk of exposure to herpes simplex virus at delivery. New England Journal of Medicine 1986; 315: 796-800.
2. Brown IA, Vontver LA, Benedetti J, et al. Effects on infants of a first episode of genital herpes during pregnancy. New England Journal of Medicine 1987; 317: 1246-1251.
3. Brown ZA, Benedetti J, Ashley RL, et al. Neonatal herpes simplex virus infection in relation to asymptomatic maternal infection at the time of labor. New England Journal of Medicine 1991; 324: 1247- 1252.
4. Brown ZA, Selke S, Zeh J, et al. The acquisition of herpes simplex virus during pregnancy. New England Journal of Medicine 1997; 337:509.
5. Brown ZA, Wald A., Ashley R., et al. Effect of serologic status and caesarean delivery on transmission rates of herpes simplex virus from mother to infant. Journal of the American Medical Association 2003; 289-203.
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13. Palasanthiran, P., Starr M., Jones C. (Editors) "Management of Perinatal Infections". Australasian Society for Infectious Disease. 2002. http://www.racp.edu.au/asid/resources_perinatal.htm.
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15. Prober CG, Sullender WM, Yasukawa LL, et al. Low risk of herpes simplex virus infections in neonates exposed to the virus at the time of vaginal delivery to mothers with recurrent genital herpes. New England Journal of Medicine 1987; 316: 240-244.
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18. Spangler JG, Kirk JK, Knudson MP. Uses and safety of acyclovir in pregnancy. Journal of Family Practice 1994; 38: 186-191.
19. Stone KM, Brooks CA, Guinan ME, Alexander ER. National Surveillance for neonatal herpes simplex virus infection. Sexually Transmitted Diseases 1989; 16: 152-156.
20. Stray-Pederson B. Acyclovir in late pregnancy to prevent neonatal herpes simplex (letter). Lancet 1990; 336: 756. Tookey PA, Peckham CS. Neonatal herpes simplex virus infection in the British Isles. Paediatric and Perinatal Epidemiology 1996; 10: 432- 442.
21. Van Everdingen JJE, Peeters MF, ten Have P. Neonatal herpes policy in the Netherlands: five years after a consensus conference. Journal of Perinatal Medicine 1993; 21: 371-375.

Herpes Virus Clinical Guidelines

The Australian Herpes Management Forum aims to improve the awareness, understanding, management and control of herpes virus infections in Australia.

The AHMF has several guidelines related to genital herpes and herpes viruses, these include:

• Managing Genital Herpes
• The Use of Type-Specific Serology for the Diagnosis of Genital Herpes
• Counselling and Communication Skills for Patients with Genital Herpes
• Preventing the Sexual Transmission of Genital Herpes
• Managing Herpes Zoster
• Managing Oral Herpes

These guidelines are published on the AHMF website at www.ahmf.com.au/guidelines. Australian health professionals wishing to receive hard copies of these guidelines should contact the AHMF on (02) 8230 3843 or AHMF Membership at www.ahmf.com.au/health_professionals/resource_kit.htm.

Disclaimer

The AHMF have made considerable efforts to ensure the information upon which the guidelines are based reproduces the evidence as accurately as possible. Users of these guidelines are strongly recommended to confirm that the information contained within them, especially drug indications, is correct by way of independent sources. The AHMF accept no responsibility for any inaccuracies, information perceived as misleading, or the success of any treatment regimen detailed in the guidelines.

Related information:

Research update - Valaciclovir to prevent recurrent herpes at delivery