1.1 MTB Step 3 - The Uncomplicated Pregnancy (Diagnosing Pregnancy & 1st Trimester Prenatal Screening) Flashcards
Cards Complete:
DIAGNOSING PREGNANCY
What are (3) Clinical Findings in Suspected Pregnancy?
- Amenorrhea
- Enlargement of Uterus
- + Urinary Beta-HCG (pregnancy) test
DIAGNOSING PREGNANCY
What are the (4) parts to Confirming Pregnancy?
- Presence of Gestational Sac with Yolk Sac: seen by transvaginal ultrasound at 4 to 5 weeks. This corresponds to a serum β-hCG level of about 1,500 mIU/mL.
- Fetal Heart Motion: seen by ultrasound at 5 to 6 weeks.
- Fetal Heart Sounds: heard with doppler ultrasound at 8 to 10 weeks.
- Fetal Movements: Felt by physician after 20 weeks gestation.
DIAGNOSING PREGNANCY
- When is an Intrauterine Pregnancy normally seen on Vaginal US?
- When is an Intrauterine Pregnancy normally seen on Abdominal US?
- Vaginal sonogram at 5 weeks gestation when serum β-hCG > 1,500 mIU
- Abdominal sonogram at 6 weeks gestation when β-hCG > 6,500 mIU
PRENATAL SCREENING
FIRST TRIMESTER
- What is the first-trimester screening test for Anemia or Blood Disorders?
- What is the Diagnostic Significance?
- CBC
- Anemia = Hb < 11 g/dL in the first and third trimesters and < 10.5 g/dL in the second trimester.
PRENATAL SCREENING
BASIC SCIENCE CORRELATE
What is Anemia in Pregnancy caused by specifically?
- Anemia in pregnancy is caused by Increased levels of Hepcidin, which Inhibits Iron Transport.
- Pregnancy Increases Iron Demand, but Hepcidin Prevents Absorption.
PRENATAL SCREENING
FIRST TRIMESTER
- What is the Most Common Cause of Anemia in the first trimester?
- Which lab value is considered the Most Reliable Indicator of Anemia?
- What WBC count is considered Abnormal?
- Iron Deficiency
- MCV
- WBC > 16,000/mm3
PRENATAL SCREENING
FIRST TRIMESTER
What is the Next Step in Management for each of the following situations?
- Decreased Hg and Decreased MCV
- Decreased Hg, Increased MCV, Increased RDW
- Thrombocytopenia (<150,000)
- Give IRON. Test for Thalassemia if anemia does not improve.
- Give FOLATE.
- Correlate clinically for ITP or HELLP Syndrome.
PRENATAL SCREENING
FIRST TRIMESTER
What are the (2) first-trimester screening tests for Blood Type, Rh, and Antibody and what is the Diagnostic Significance for each?
- Type & Screen: Rh-negative mothers may become sensitized (anti-D Ab) → risk of erythroblastosis fetalis in the next pregnancy.
- Coomb’s Test (Direct & Indirect): Indirect Coombs test (or atypical antibody test [AAT]) detects atypical RBC Ab’s.
PRENATAL SCREENING
FIRST TRIMESTER
What is the Next Step in Management for Rh-negative Mothers?
Give RhoGAM to Rh-negative mothers at 28 weeks after first rescreening for the absence of anti-D antibodies or after any procedure (CVS, amniocentesis) and after delivery.
PRENATAL SCREENING
FIRST TRIMESTER
What are the (2) first-trimester Genitourinary screening tests and what is the Diagnostic Significance for each?
- Cervical Pap Smear: Detects cervical dysplasia or malignancy.
-
Urinalysis & Urine Culture:
- UA - Screen for underlying renal disease and infection.
- UCx - Screen for asymptomatic bacteriuria (ASB).
PRENATAL SCREENING
FIRST TRIMESTER
What is the Next Step in Management for Asymptomatic Bacteriuria (ASB) in the first trimester?
Cephalosporins, Amoxicillin
- Always treat ASB in pregnancy to prevent pyelonephritis (30% risk when untreated).
- Need test of cure in pregnant women.
PRENATAL SCREENING
BASIC SCIENCE CORRELATE
- What type of parasite is Chlamydia trachomatis?
- What type of parasite is Neisseria gonorrhea?
- Chlamydia trachomatis is an Obligate Intracellular Parasite (It needs a host cell to survive).
-
Neisseria gonorrhea is a Gram-Negative Diplococcus that grows on Chocolate Agar.
- Nuclear acid amplification test (NAAT) is the test of choice.
PRENATAL SCREENING
FIRST TRIMESTER
What are the (2) first-trimester screening tests for Immunization Status and what is the Diagnostic Significance for each?
- Rubella Antibody: (–) Rubella IgG Ab’s means ↑ risk of primary rubella infection.
- Hepatitis B Surface Antigen: (+) HBsAg indicates risk for vertical transmission of HBV.
PRENATAL SCREENING
FIRST TRIMESTER
What is the Next Step in Management for first trimester (-)Rubella IgG status?
- Do not give Rubella immunization in pregnancy.
- Immunize seronegative patients after delivery.
PRENATAL SCREENING
FIRST TRIMESTER
What is the Next Step in Management for first trimester (+)HBsAg status?
(+) HBsAg: Order HBeAg:
- (+) HBeAg signifies a highly infective state.
PRENATAL SCREENING
FIRST TRIMESTER
What are the (2) first-trimester screening tests for Syphilis Infection and what is the Diagnostic Significance?
VDRL or RPR
- Confirm (+) VDRL/RPR with Treponema-specific tests (MHATP or FTA).
- Alternatively, may start with Treponemal-specific tests (EIA/CIA) followed by VDRL/RPR (“reverse algorithm screening”).
PRENATAL SCREENING
FIRST TRIMESTER
What is the Next Step in Management for confirmed Syphilis infection in the first trimester?
(+) Confirmatory Test = Treat with IM Penicillin.
Penicillin Allergy: Desensitize and then treat with Penicillin.
PRENATAL SCREENING
FIRST TRIMESTER
What is the first-trimester screening test for HIV Infection and what is the Diagnostic Significance?
ELISA
Confirm (+) ELISA screen with Western blot test (presence of HIV core and envelope antigens).
PRENATAL SCREENING
FIRST TRIMESTER
What is the Next Step in Management for confirmed HIV+ infection in the first trimester?
- All babies born to HIV (+) women will be HIV antibody (+) (passive transport of maternal Ab’s).
- (+) Ab’s do not indicate an infection in an infant.
- Antiretrovirals are recommended in pregnancy.
- Give Zidovudine in labor
PRENATAL SCREENING
FIRST TRIMESTER
What is the first-trimester screening test for Chlamydia/Gonorrhea Infection and what is the Diagnostic Significance?
Cervical Culture
- Gram stain
- Chlamydia and Gonorrhea culture
Also treat Trichomonas Vaginalis (can cause premature labor).
PRENATAL SCREENING
FIRST TRIMESTER
What is the Next Step in Management for confirmed Chlamydia/Gonorrhea infection in the first trimester?
(+) Chlamydia/Gonorrhea
- IM Ceftriaxone
- PO Azithromycin
(+) Bacterial Vaginitis
- PO or Vaginal Metronidazole or clindamycin
(+) Trichomonas Vaginalis
- PO Metronidazole for mother and partner
OPTIONAL PRENATAL SCREENING
FIRST TRIMESTER
What are the (2) optional first-trimester screening tests for Tuberculosis?
Quantiferon Gold (QFT) (preferred) or PPD
OPTIONAL PRENATAL SCREENING
FIRST TRIMESTER
What is the Next Step in Management for confirmed Tuberculosis in the first trimester?
- If (–) QFT or (–) PPD: No further follow-up is needed.
- If (+) QFT or (+) PPD: Order chest x-ray to rule out active disease.
Treatment for a Positive screen:
- (+) QFT or (+) PPD and (–) CXR: INH and B6 for 9 months.
- (+) QFT or (+) PPD and (+) CXR and (+) Sputum: Begin triple therapy antituberculosis Rx if sputum stain positive.
- Obtain sputum for culture.
- Avoid streptomycin in pregnancy because of the risk of ototoxicity in the fetus.
OPTIONAL PRENATAL SCREENING
FIRST TRIMESTER
What are the (3) optional first-trimester screening tests for Trisomy 21 (Down Syndrome)?
- β-hCG
- Pregnancy Associated Plasma Protein A (PAPP-A)
- Fetal Nuchal Translucency
OPTIONAL PRENATAL SCREENING
FIRST TRIMESTER
What is the Next Step in Management for a (+) Trisomy 21 (Down Syndrome) screening test in the first trimester?
A (+) Screening test is confirmed with Chorionic Villus Sampling (CVS) or Amniocentesis in the first trimester.
