Ch 18 Effects of Maternal Disease on Pregnancy Flashcards
What does TORCH stand for?
Toxoplasmosis, others viruses, rubella, cytomegalovirus + herpes
What is TORCH?
-It is common maternal infections associated with fetal congenital anomalies
-These tests check for several different infections in a newborn
What is toxoplasmosis?
-Parasitic infection transmitted through undercooked/raw meat that is contaminated
-Pregnant pt should not handle cat litter b/c of risk of contracting the parasite by inhaling the dust
Does the obstetric pt typically experience symptoms with toxoplasmosis?
No, asymptomatic
(15-17% of maternal infection in 1st trimester can transfer to the placenta + fetus causing anomalies)
Severe toxoplasmosis infection can present as what 3 things in the fetus + neonate?
-CNS anomalies
-Ascites
-Hypatosplenomegaly
Is acquiring toxoplasmosis in early or late pregnancy more likely going to spread to the fetus?
Late - acquiring the infection during 3rd trimester will more likely affect fetus
What does “others” represent in TORCH?
-Syphilis
-Varicella-zoster
-Parvovirus B19 (5th disease)
Infections with syphilis in early pregnancy may result in what?
Spontaneous abortion
Fetal contamination with maternal chickenpox infection results in what?
Fetal varicella-zoster
The risk for fetal anomalies is highest in which trimesters?
1st + 2nd
List the sonographic evidence of varicella-zoster virus in the fetus that is displayed in the image on the lecture slide?
Echogenic hepatic foci + abdomen
What are the 2 fetal complications when exposed to acute parvovirus B19?
-Death
-Nonimmune hydrops
(these occur within 12 weeks following infection in pregnancy)
What are noninvasive ways to diagnose fetal anemia + nonimmune hydrops?
An anatomic survey + measurement of peak systolic flow of MCA
What infection was one of the 1st recognized maternal infections that resulted in fetal anomalies?
Rubella (aka German or 3 day measles)
(malformations occur with 1st trimester exposure)
How does gestational herpesvirus infections reach the embryo/fetus?
Through the placenta by ascending through the cervix OR through fetal contact with birth canal during vaginal delivery
What is the m/c known cause of congenital infections in humans?
CMV (cytomegalovirus virus)
Is there a high or low rate of transmission of the herpes simplex virus infection to the neonate?
High - associated with cranial malformations, microphthalmia + hepatosplenomegaly
The presence of the virus in the maternal genital tract at time of delivery indicates the need for what?
C-section - b/c of high neonatal infection rate with vaginal delivery
What is a typical finding when a maternal infection has crossed the placenta?
Polyhydramnios
CMV infection + toxoplasmosis m/c result in what?
Periventricular calcifications
What is the m/c maternal disorder the OB sonographer encounters?
Diabetes mellitus
What are the types of diabetes mellitus?
Type 1: insulin dependent (juvenile onset)
Type 2: noninsulin dependent (adult onset)
Secondary: pancreatic disease, hormones, drugs, chemicals, genetic syndromes
Impaired glucose tolerance + gestational diabetes is a condition that only occurs when?
During pregnancy
High blood sugar levels (hyperglycemia) in the mother results in the disruption of what?
Embryonic organogeneisis
What pathology occurs in 6.4% of diabetic mothers?
SUA
(may also experience IUGR or macrosomia - due to hyperglycemia)
What is fetal macrosomia?
-Newborn who is much larger than average
-Fetal weight over 4,500g (9 lb 9 oz) or above 90th percentile for gest age
If a mother has diabetes, an anatomic survey b/w what weeks will allow for screening for malformations? When should follow up exams occur?
-B/w 18-22 weeks for anatomic survey
-Follow up exams done every 4-6 weeks for fetal growth + estimated weight
What causes placental enlargement in fetus’s whose mother has diabetes?
Due to chronic hyperglycemia
Gestational diabetes m/c begins during what month of pregnancy?
B/w month 5 or 6 (24-28 weeks) + disappears shortly after delivery
What type of test is the preferred method to diagnose gestational diabetes?
Glucose tolerance test (done b/w weeks 24-28)
What is the glucose tolerance test?
-Drinking glucose solution + checking glucose level after 1 hour
-A higher glucose level requires a 3 hour glucose tolerance test
-The diagnosis is made when 2 or more high glucose levels during the 3 hour test occur
What is toxemia?
Preeclampsia - 3rd trimester disease characterized by maternal edema, hypertension, proteinuria + CNS irritability
2 stages of toxemia?
1: Preeclampsia (hypertension with proteinuria and/or edema)
2: Eclampsia (when 1 or more convulsions occur, there is an increased maternal + fetal mortality)
When preeclampsia develops before 26 weeks gestation, what happens?
A prenatal mortality rate as high as 20% has been reported
Preeclampsia m/c occurs in what age?
Young primigravidas (preg for 1st time) + in older multiparas (preg multiple times)
What 3 factors are associated with preeclampsia?
-Low birth weight
-Fetal distress
-Placental abruption
What drugs can be prescribed to help control BP + seizures?
BP: antihypertensive drugs
Seizures: anticonvulsant medication
If toxemia is present, will they deliver the fetus right away?
Yes! Immediately
What is the HELLP syndrome?
Hemolysis, Elevated Liver enzymes, Low Platelets
Are HELLP symptoms similar to preeclampsia findings?
Yes - often go together
When does HELLP m/c occur in pregnancy?
3rd trimester - rarely occurs earlier
What women m/c have HELLP?
-African descent
-Nulliparous white women with preeclampsia + family history
We should be suspicious of placental abruption when the mother experiences what signs?
Abdominal pain in a women with chronic hypertension
Can hypertension occur in pregnancy w/o the development of toxemia?
Yes
What do serial S/D ratios detect?
The development of increased placental vascular resistance
Does hypertension of any type pose a risk to the mother + fetus?
Yes
Excessive consumption of alcohol (a teratogen) during pregnancy can result in what?
Fetal alcohol syndrome (FAS)
What is the leading cause of mental retardation in the West?
FAS - results in cognitive + functional disabilities as well as structural + growth anomalies in the fetal period
