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  • What viral and parasitic infections affect the fetus and can alter maternal, fetal, or newborn outcomes?

  • How are congenital infections prevented, diagnosed, and followed by OB/Gyn providers?

  • What infections can occur at any gestation, but are seen in and managed while a woman is in labor?

  • What is the best way to treat and manage infections that affect the fetus?

CASE 34-1

A 36 y.o. woman presented to L&D at 28 weeks gestation with complaints of fever and malaise for 3 days, 1 day of decreased fetal movement, and regular contractions. The pregnancy was the result of IVF for tubal factors. Her husband was born and raised in Peru. Most of the relatives from both sides of the family live in Peru. The patient had visited outside the United States only as a child. There was no recent family history of similar symptoms. During the hospitalization, the patient’s fever was low grade (38.0 degrees C) and intermittent. Workup for chorioamnionitis was negative. She received magnesium sulfate for fetal neuroprophylaxis and betamethasone for fetal lung maturation. On hospital day 4, she went into active preterm labor, and an emergency C-section was performed for FHR abnormality. The baby was admitted to the NICU and started on treatment for possible early-onset sepsis secondary to the preterm delivery and maternal fever. Postdelivery, the patient’s fever increased and became persistent. She developed tachycardia and shortness of breath. Cultures were obtained. Chest X-ray showed findings consistent with atypical pneumonia. The patient was placed on broad-spectrum antibiotics and transferred to the ICU.

Most infections that occur in pregnant women resolve spontaneously or after treatment. These infections typically have no visual effect on the fetus. This chapter will focus on several microorganisms that initially infect the mother and go on to infect and have an effect on the fetus. Different viruses, bacteria, protozoa, and fungi can infect the pregnant woman and cross the placenta. Maternal infectivity and transmission through the placenta to infect the fetus may be increased at a specific gestational age range, or they can occur at any time during gestation. Women may be minimally symptomatic and have few or no clinical signs. Some infections are fatal, causing miscarriage or fetal or newborn death. The same pathogen infecting women at the same or different gestational age may have no effect (or no visible effect, at least) on the fetus or newborn for many years after birth. Other infections may not affect the fetus until the patient is in labor, or they can cause the patient to go into labor.

There are a few generalizations that can assist in the management of infections during pregnancy. There are many ways that infections may present, progress, and respond to treatment. When a patient is exposed to an infectious agent, the virulence, inoculum size, incubation time, portal of entry, maternal immune response, and ability of the organism to penetrate ...

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