Ebook ABC of sexually transmitted infections (6E): Part 1

es
Mother
• The risk of vertical transmission of genital herpes depends
whether it is the first episode or recurrent herpes
• It can be difficult to distinguish between recurrent and first
episode genital herpes; type-specific herpes simplex virus (HSV)
serology may be helpful

First episode
•

•
•

•

•

•

Figure 11.3 Congenital syphilis of infant. Courtesy of CDC/Dr Norman Cob.

Give oral or intravenous aciclovir depending on the clinical
severity. (Aciclovir is not licensed for use in pregnancy but has
been used extensively in pregnant women with no reported
problems.)
Vaginal delivery should be planned
Daily suppressive aciclovir from 36 weeks reduces the likelihood
of HSV lesions at term and the need to offer caesarean section
(CS)
The risk of transmission is greater (up to 40%) when the first

episode occurs in the third trimester
CS should be offered to all women with first episode at the time
of delivery, or within 6 weeks of expected date of delivery (EDD)
or onset of labour
If vaginal delivery is unavoidable, aciclovir treatment of the
mother and baby should be considered

Recurrent episodes
•

•

•

•

(a)
•

(b)

Figure 11.4 Congenital syphilis on: (a) teeth, and (b) mouth.

Recurrences during pregnancy pose no threat to the pregnancy
or fetus
The risk of neonatal herpes with recurrent HSV at onset of labour
is <1%. This suggests that passive immunity from maternal
antibodies is protective to the infant
Avoid fetal scalp monitors as they can be a site of inoculation of
virus and increase transmission risk

CS can be considered for women with recurrent HSV at the onset
of labour; risk of transmission with vaginal delivery is small so
needs to be weighed against the risks of CS to the mother
Daily suppressive aciclovir from 36 weeks reduces recurrent
clinical HSV and viral detection at the time of delivery and the
need to offer CS

Infant
• HSV-1 and HSV-2 can cause neonatal herpes
• Incidence is 1 in 60 000 live births in the United Kingdom; this
is lower than other European countries and the United States.
Most cases are from direct contact with infected maternal genital
secretion but postnatal transmission can occur from nosocomial
or community-acquired herpes infection


STIs and HIV in Pregnancy

•

•

•

Neonatal herpes is almost always symptomatic and frequently
fatal
There are three categories of infection: localised to the site of
viral entry (skin, eye, or mouth); encephalitis; and disseminated
infection. Disseminated infection has the worst prognosis
Diagnosis needs a high index of suspicion. Vesicular fluid can be

sent for electron microscopy and HSV polymerase chain reaction
(PCR)

HIV infection
Mother
• In 2008, 0.21% of women giving birth in England and Scotland
were HIV-infected
• HIV prevalence among pregnant women in London has been
stable at 0.37% since 2004
• Prevalence in pregnant women outside London has increased
fivefold in the past decade but remains relatively low at 0.15% in
2008 (Figure 11.5)
• Sub-Saharan African-born pregnant women outside London
have significantly higher HIV prevalence (3.1%) than those living
inside London (2.3%)
• Prevalence in United Kingdom-born women was low in 2008
(0.05%) but there has been a statistically significant increase
since 2000. Detection of HIV in pregnant women in the United
Kingdom remains high; >90% are diagnosed before delivery
• Screening for STIs and genital infections should be performed
early in the pregnancy
• HIV probably has little effect on pregnancy outcome but highly
active antiretroviral therapy (HAART) appears to increase
preterm birth
• HIV can be transmitted to the infant in utero, at delivery, and by
breastfeeding; the majority of cases occur during delivery
• Risk of transmission depends on maternal HIV viral load; higher
viral loads are associated with increased risk
• Prior to the routine use of HAART, the transmission rate was
13% in Europe in non-breastfeeding women. Breastfeeding adds

about a further 15% transmission rate

•

63

With HAART and/or elective CS, transmission rate can be
reduced to <2%

Interventions to prevent mother–child transmission
Women not already taking HAART should commence standard
HAART during the second trimester in order to achieve undetectable viral load by 36 weeks allowing vaginal delivery. Some
mothers who achieve an undetectable viral load still prefer a
planned CS at 39 weeks. Women receiving no HAART, or those
unable to achieve undetectable viral load, should have a planned
CS at 38 weeks.
Infants should be given postexposure prophylaxis with antiretroviral therapy for 4 weeks and breastfeeding should be avoided.

Infant
• Antenatal HIV screening and interventions to prevent
mother–child transmission (MTCT) led to a dramatic fall in
infected infants in the United Kingdom
• The MTCT rate in 1993, when interventions were virtually
non-existent, was 25.6%
• Between 2000 and 2002, the MTCT rate fell to 1.6%; 2003–2006
to 1.0%. Now MTCT rates are 0.7% among mothers on HAART
• No significant difference between mode of delivery (planned CS
versus vaginal delivery) is seen in mothers on HAART
• There is no evidence of congenital abnormalities with exposure
to HAART, even in the first trimester

• Infants are routinely given postexposure prophylaxis with
antiretroviral therapy for 4 weeks
• Strict formula feeding only
• HIV DNA PCR on peripheral blood lymphocytes should be
performed at 1 day, 6 weeks, and 12 weeks of age
• If all tests are negative, and the infant is not being breastfed, the
parents can be informed that the infant is not HIV infected
• Loss of the maternal HIV antibodies should be confirmed at
18 months

Further reading
50

London
Rest of England
Scotland

45
40
35
30
25
20
15
10

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

0

1997

5

Figure 11.5 Rates of HIV prevalence in pregnant women from 1997 to
2007. (Data from unlinked anonymous survey of newborn infant dried blood
spots.)

de Ruiter A, Mercey D, Anderson J, Chakraborty R, Clayden P, Foster G,
et al. British HIV Association and Children’s HIV Association guidelines

for the management of HIV infection in pregnant women 2008. HIV Med
2008;9:452–502.
Giraudon I, Forde J, Maguire H, Arnold J, Permalloo N. Antenatal screening
and prevalence of infection: surveillance in London, 2000–2007. Euro
Surveill 2009;14(9):8–12. Available online at osurveillance
.org/ViewArticle.aspx?ArticleId = 19134.
Goh BT, Thornton AC. Antenatal screening for syphilis. Sex Transm Inf
2007;83:345–6.
National Institute for Health and Clinical Excellence. Antenatal Care: Routine
Care for the Healthy Pregnant Woman. NICE, March 2008.
Royal College of Obstetricians and Gynaecologists. Green-top Guideline no 30:
Management of Genital Herpes in Pregnancy. RCOG, September 2007.