infections in pregnancy jonathan schaffir, md associate professor dept of obstetrics &...
TRANSCRIPT
Infections in Pregnancy
Jonathan Schaffir, MD
Associate Professor
Dept of Obstetrics & Gynecology
The Ohio State University College of Medicine
Objectives
Describethe routes of infection in
pregnancy and when infection is likely to
occur
the different types of infections that occur
in pregnancy, including “TORCH” infections, and their clinical significance
At the end of this module, you will learn
how to
Pregnant uterus = sterile environmentFetus with immature immune system (begins development at 14 weeks)
The Fetus
Routes of infection in pregnancy
Transcervical
Transplacental
Iatrogenic
Transcervical infection
Cervical mucus provides barrier between vagina and uterine cavity
Thickened under influence of progesterone
Intraamniotic infection
Intraamniotic infection: pathogens
• Chlamydia• GonorrheaSTDs
• Group B strep• E. coli• Bacteroides• Mycoplasma/ ureaplasma
Pathogenic vaginal
flora
Review question
In which of the following scenarios is an intrauterine infection the most likely?• After having a Pap smear at 14 weeks• After having sexual intercourse at 28 weeks• After having a pelvic exam at 37 weeks• After 12 hours of labor with membranes
ruptured and cervical dilation of 6 cm
Transplacental infection
Viruses and bacteria that have infected the maternal circulation can in theory reach the fetus through the placenta
“TORCH” infections
Refers to a group of pathogens that can cause transplacental infection:
Toxoplasmosis
Other (syphilis)
Rubella
Cytomegalovirus
Herpes /HIV/ Hepatitis (rarely)
Toxoplasmosis
Parasitic coccidium can be asymptomatic in immunocompetent adults
Fecal-oral transmission from cats, soil
May cause infection of brain or retina, leading to blindness, severe mental retardation
Syphilis
Sexually transmitted spirochetal disease Phenotype depends on when in pregnancy infected Can cause mental retardation, deafness
Saddle noseHutchinson’s teeth Saber shins
Rubella
Maternal infection now rarely seen due to vaccination program
Triad of microcephaly, heart defects, and cataracts; deafness also occurs
Cytomegalovirus
Very common (50-80% of adults have had it)
Often contracted by oral route by infected children (day care/ preschool)
Usually mild symptoms Can be reactivated Infant may have mental
retardation, retinitis, hepatosplenomegaly and rash
“Blueberry muffin rash”
Herpes
More commonly a concern at delivery, with vertical transmission due to direct contact
May be transmitted transplacentally when mother has primary infection (acute viremia)
Possible CNS manifestations, death
HIV
Transmission depends on viral load, degree of intra-partum exposure and unknown immunological factors
Not associated with birth defects
Rate of transmission drastically reduced with prenatal and intrapartum treatment
Review question
A boy comes to your pediatric clinic for evaluation of mental retardation and learning delays. You notice that his front teeth are peg-like and his shins are bow-shaped. His mother was most likely infected with:• Toxoplasmosis• Syphilis• Rubella• Cytomegalovirus
Some other important infections to know about
Parvovirus
ListeriaMalaria
Parvovirus
Common infection among children (“5thdisease”) If contracted in pregnancy can induce hemolysis and
severe anemia in fetus Causes hydrops (diffuse swelling) and heart failure
Listeria
Predilection for pregnant women Mild illness in mother; devastating to fetus Frequently causes death in utero Usually contracted through contaminated food
Malaria
Does not cause fetal infection
Infects the placenta, where parasites proliferate
Causes miscarriage, restricted fetal growth, and low birthweight
Prophylaxis recommended in endemic areas
Review question
On a routine prenatal visit at 24 weeks, you find that the fetus has no heartbeat. Which of the following associations would lead you to believe the mother contracted listeria?
• Fetal hydrops• Recent safari in Africa• Recent high fever and shaking chills• Recent stay on a cousin’s farm
Conclusions
Fetus is well-protected from
external pathogens Infections that can breach
these protections may have devastating consequences
Important to prevent infection with careful screening, vaccination, patient education and appropriate treatment
