23.4 Perinatal Infections: Triple Elimination (HIV, Syphilis, Hepatitis B), Group B Streptococcus, Chorioamnionitis, Gonorrhea & Chlamydia, Condyloma, Herpes and the TORCH Infections

Why this area matters

TOS area J asks you to:

• classify the microorganisms that infect pregnant women and their fetuses, including vertical transmission;
• correlate symptoms with the course of pregnancy;
• treat without fetal or maternal harm, applying the physiologic changes of pregnancy to drug therapy;
• choose screening tests and preventive measures, including the manner of delivery.

The DOH pursues the elimination of mother-to-child transmission of HIV, syphilis and hepatitis B ("triple elimination"). The Philippines has a high hepatitis B burden and a rapidly growing HIV epidemic, so screening at the first antenatal visit and linkage to treatment are essential.

Hepatitis B

• Transmission: most mother-to-child transmission happens at delivery. Without prophylaxis, about 90% of infants of HBeAg-positive mothers become chronic carriers.
• Screening: all pregnant women are tested for HBsAg.
• Infants of HBsAg-positive mothers:
  • hepatitis B vaccine and hepatitis B immune globulin (HBIG) within 12 to 24 hours of birth;
  • complete the vaccine series;
  • test for HBsAg and anti-HBs after the series.
• Mothers with high viral load (HBV DNA above about 200,000 IU/mL) or positive HBeAg: give tenofovir from about 28 weeks to further reduce transmission.
• Delivery and breastfeeding: cesarean delivery is not needed, and breastfeeding is allowed once the infant has received immunoprophylaxis.

HIV

• Screening: screen at the first visit, and repeat in the third trimester for women at high risk.
• ART: all pregnant women with HIV start or continue lifelong ART (a dolutegravir-based regimen) as early as possible.
• Delivery:
  • with a suppressed viral load near term, delivery is vaginal;
  • with a high or unknown viral load near term, planned cesarean at 38 weeks and intrapartum zidovudine are considered;
  • avoid prolonged ruptured membranes, fetal scalp electrodes and routine episiotomy.
• Infant: antiretroviral prophylaxis, and early nucleic acid testing because maternal antibodies persist.
• Feeding: where safe replacement feeding is not assured, WHO supports breastfeeding with maternal ART.

Syphilis, gonorrhea and chlamydia

• Syphilis:
  • screen at the first visit with RPR or a rapid treponemal test, and again in the third trimester for women at high risk;
  • treat with benzathine penicillin G, desensitizing women with penicillin allergy;
  • untreated, it causes miscarriage, stillbirth, hydrops, prematurity and congenital syphilis;
  • treat partners;
  • test the infant at birth.
• Gonorrhea and chlamydia:
  • cause cervicitis, PPROM, preterm birth, postpartum endometritis and ophthalmia neonatorum;
  • gonococcal conjunctivitis appears in 2 to 5 days and is hyperacute and purulent, risking corneal perforation;
  • chlamydial conjunctivitis appears in 5 to 14 days, and chlamydia also causes neonatal pneumonia;
  • treat gonorrhea with ceftriaxone and chlamydia with azithromycin (doxycycline is avoided in pregnancy);
  • all newborns receive eye prophylaxis.

Group B streptococcus and intra-amniotic infection

• GBS:
  • colonizes the vagina and rectum of 10% to 30% of women;
  • causes early-onset neonatal sepsis, pneumonia and meningitis;
  • prevented by screening at 36 to 37 weeks and intrapartum IV penicillin or ampicillin, given at least 4 hours before delivery, for carriers and women with risk factors;
  • details of the regimen are in the prenatal care section.
• Intra-amniotic infection (chorioamnionitis):
  • an ascending polymicrobial infection, often after prolonged rupture of membranes or many vaginal examinations;
  • maternal fever with fetal tachycardia, maternal leukocytosis, uterine tenderness or foul or purulent amniotic fluid;
  • treat with IV ampicillin plus gentamicin, adding clindamycin or metronidazole for anaerobes after a cesarean, and deliver;
  • complications are neonatal sepsis, cerebral palsy, maternal sepsis, atony and PPH.

Condyloma acuminatum and genital herpes

• Condyloma acuminatum (HPV 6 and 11):
  • warts may enlarge rapidly in pregnancy;
  • treat with cryotherapy, trichloroacetic acid or excision;
  • avoid podophyllin and imiquimod;
  • cesarean delivery is needed only if warts obstruct the birth canal or risk massive bleeding;
  • rarely, infants develop recurrent respiratory papillomatosis.
• Genital herpes:
  • the risk to the newborn is highest after a primary infection in late pregnancy;
  • give suppressive acyclovir or valacyclovir from 36 weeks to women with a history of herpes;
  • perform cesarean delivery if there are active genital lesions or prodromal symptoms at labor.

TORCH and other congenital infections

Dengue and malaria in pregnancy raise the risk of hemorrhage, preterm birth and maternal death, and need hospital care. COVID-19 in pregnancy raises the risk of severe illness and preterm birth, and vaccination is recommended.