Second and Third Trimester Complications - Cruz Flashcards
Define:
- First trimester
- Second trimester
- Third trimester
- First: last missed menses to 13 weeks
- Second: 13-25 weeks
- Third: 26 weeks to estimated due date
Name the diseases that make up TORCH
- Toxoplasmosis
- ‘Other’ (syphilis and Parvovirus B19)
- Rubella
- CMV
- HSV
What organism is impicated in toxoplasmosis?
What is the essential reservoir for this disease? Why is this important for pregnant women?
toxoplasma gondii (coccidian parasite)
Cats. Pregnant women should not handle cat feces (fecal->oral->transplacental transmission)
Describe the effects of toxoplasmosis in:
- First trimester
- Second trimester
- Third trimester
How is this diagnosed?
- First: often results in death
- Second: hydrocephalus (ventriculomegaly), intracranial calcifications, chorioretinitis
- Third: often asymptomatic at birth
Dx: maternal +IgM and +IgG, fetal amniotic fluid PCR
Treponema pallidum causes what disease?
Describe its morphology and gram-staining
Syphilis
G(-) spirochete
When does congenital syphilis have the greatest chance of causing spontaneous abortion?
Give some other clinical manifestations
First trimester
- Stillbirth
- non-immune hydrops
- preterm birth
- hepatomegaly
- ascites
- anemia, thrombocytopenia
What screening tests are used to detect syphilis?
What confirmatory tests are used?
Screening: RPR and VDRL
Confirm dx: FTA-ABS, MHA, dark-field microscopy, DFA
Name the TORCH organism that is most closely associated with hemolysis and transient aplastic crisis
How is it transmitted?
Give some (fetal) clinical manifestations
Diagnostic tests?
Parvovirus B19
Tx: respiratory droplets with transplacental transfer
- anemia
- acute myocarditis
- edema/hydrops
- intrauterine fetal demise
Dx: maternal +IgM and +IgG, PCR of amniotic fluid
Increased blood flow velocity in the fetal brain is worrisome for which TORCH bug?
Parvovirus B19
What family of viruses does Rubella belong to?
How is it transmitted to the fetus?
Why (theoretically) should we be less concerned about this virus these days?
Togaviridae family of RNA viruses
Tx: respiratory droplets and transplacental transfer
Vaccine available
What congenital defects are associated with Rubella?
How is it diagnosed?
- Deafness
- Eye defects (cataracts and retinopathy)
- CNS defects
- Cardiac malformations
- microcephaly, mental retardation, pneumonia, growth restriction, hepatosplenomegaly, hemolytic anemia, thrombocytopenia
Dx: increased IgM and IgG titers and PCR of amniotic fluid
Give (3) possible transmission modes for CMV to the fetus/infant
- Transplacental
- Perinatal (inoculation in vagina or breast milk)
- Bodily fluid contact (Don’t kiss the baby, grandma)
Periventricular calcifications are a common finding with which TORCH bug?
Describe the characteristic histologic finding seen?
CMV
“Owl’s Eye” = enlarged (cytomegalic) cells with large basophilic nuclear inclusions
Is transplacental infection common with HSV?
Give some other transmission modes
No. Transplacental infection is rare.
Other modes:
- Perinatal (contact with vagina)
- Contact after membrane rupture
- Direct contact with other affected areas
Describe the clinical manifestation of fetal HSV infections
Microcephaly
ventriculomegaly
spasticity, echogenic bowel, hepatosplenomegaly, flexed extremities
What organism is identified with a Tzanck Smear?
What other diagnostic tools might be used in the identification of this organism?
HSV
Others: culture, PCR, serology
Define cervical insufficiency
Give some risk factors
painless cervical shortening or dilation leading to pregnancy loss
Risk factors:
- collagen abnormalities
- uterine abnormalities
- prior obstetric trauma
- mechanical dilation
- prior 2nd trimester loss
What is cervical cerclage?
A suture technique used to reinforce closure of the cervix in cases of cervical insiffiency
How are gross fetal anomalies usually identified?
fetal ultrasound
What is Preterm Premature Rupture of Membranes (PPROM)?
What are its risk factors?
How is it diagnosed?
chorioamniotic membrane rupture before the onset of labor in pregnancies at less than 37 weeks of gestation
Risk factors: preterm labor, short cervix, advanced cervical dilation
Diagnosis: direct visualization of fluid with ferning on microscopy
Define preterm labor
Labor/birth between 20 weeks and <37 weeks
What is the #1 cause of perinatal morbidity and mortality in developed countries?
Give some risk factors
preterm labor/birth
Risk factors:
- premature activation of the maternal or fetal HPA axis
- exaggerated inflammatory response or infection
- placental abruption
- pathological uterine distension
What is placenta previa?
Is it painful?
- Placenta located near (marginal) or over (complete) the internal cervical os
- Painless with no contractions
Give some risk factors for placenta previa
- Smoking
- Advanced maternal age
- Multiple gestation
- Uterine anomalies
- Scarring from previous pregnancies
Define placenta accreta
Why is this a problem?
Implantation extends into the basal zone of the endometrium
It increases difficulty in removing the entire placenta during delivery, leading to higher risk of hemorrhage and hysterectomy following delivery
What is placenta percreta?
What are its risk factors?
implantation that extends into the uterine serosa and/or adjacent organs
Risk factors:
- multiple cesarean sections
- placentra previa
What is placenta increta?
Implantation that extends into the myometrium
What is placental abruption?
Give some sumptoms/clinical features
Give some key risk factors
Placental separation due to hemorrhage into the decidual basalis before birth
- Vaginal bleeding
- uterine tenderness
- May or may not show uterine heart tones
Risk factors:
- prior abruption
- trauma
- PPROM
- HTN
- Smoking and cocaine abuse
What is velamentous cord insertion?
The umbilical cord attaches to the chorion and amnion rather than the placenta. The umbilical vessels continue on to the placenta between these two membranes. This arrangement makes the umbilical vessels prone to tearing.
Serious fetal blood loss may occur
Define macrosomia
Define intrauterine growth restriction
Estimated fetal weight >4500 grams (~9.9 lbs)
Estimated (via ultrasound) fetal weight <10th percentile
Which maternal anatomical measrement should be a part of a normal 20wks gestation ultrasound scan?
Cervical length (screen for cervical insufficiency)
