M3 ALIMNZTN Flashcards
A standard 300 mcg dose contains enough anti-D immunoglobulin to prevent sensitization from up to __ ml of whole fetal blood or __ ml of RhoD-positive red blood cells.
30 mL
15 mL
High-risk events where Rh anti-D immunoglobulin is indicated include, but are not limited to the following EXCEPT
a. threatened/spontaneous/induced abortion
b. trauma
c. invasive procedures
d. ectopic pregnancy
e. molar pregnancy.
f. NOTA, all are included
F
Percentage of Rh-negative patients that will become sensitized to Rh-positive fetus in the third trimester
1-2%
Which of the following statements regarding Rh-negative patients and antibody screening during pregnancy is true?
A. Hemolysis from isoimmunization may cause erythroblastosis fetalis
B. Anti-Lewis antibody is clinically significant to the fetus
C. Rh-positive mothers should be offered Rho(D) immune globulin
D. Rho(D) immune globulin should not be given to Rh-negative patients involved in a motor vehicle accident
A
All Rh-negative women should receive Rho(D) immune globulin at what AOG, if fetus is known to be Rh-positive
28 weeks AOG
What do you call the test commonly used to detect fetal red cells in the maternal circulation, and is recommended for women over 12 weeks of gestation
Kleihauer-Betke test
What do you call the qualitative test that identifies whether fetal D-positive cells are present in the circulation of a D-negative woman.
Rosette Test
Which of the following can cross the placenta
a. anti-D IgG antibodies
b. anti-D IgM antibodies
c. both
d. neither
A
A 24-year-old G2P1 female presents for a routine prenatal appointment at 14 weeks gestation. Her previous pregnancy was affected by hemolytic disease of the fetus, and newborn (HDFN) and the patient is pregnant with the same partner. She denies vaginal bleeding, vaginal discharge, leaking of fluids, or cramping. She believes she feels fetal movement intermittently. Results of initial prenatal labs show blood type A-negative, antibody positive, HIV negative, HBsAg negative, RPR negative, gonorrhea negative, chlamydia negative, and rubella non-immune. Which of the following is the next best step in the management of this patient?
A. Administer MMR vaccine during clinic appointment
B.Order Maternal titers every month until 24 weeks gestation
C. Order Maternal titers every month until 24 weeks gestation, repeat titer every two weeks after 24 weeks of gestation
D. Titers are not recommended, serial MCA testing should be initiated
D
In patients with a prior pregnancy affected by HDFN, maternal titers should not be used to decide when to initiate fetal surveillance.
Titers are ordered in the first affected pregnancy.
This patient has a history of prior pregnancy affected by HDFN. MMR vaccine is contraindicated in pregnancy.
Which of the following is NOT a potentially sensitizing event for development of red blood cell isoimmunization in pregnancy?
A Termination of pregnancy or evacuation of retained products of conception (ERPC) after miscarriage
B Ectopic pregnancy
C Painless vaginal spotting <12 weeks
D Intrauterine death
E External cephalic version
F Delivery
C
C is the correct answer. Currently, anti-D is not recommended for painless bleeding prior to 12 weeks gestation; however, if bleeding is heavy or painful, treatment should be considered.
Prevention of Rhesus haemolytic disease – which of the following are true?
A Exogenous anti-D administration ‘mops up’ fetal red cells that have crossed the placenta, by binding to their antigens, thereby preventing recognition by the mother’s immune system.
B Anti-D routinely given to all women who are Rhesus negative will reduce the rate of isoimmunization in a first pregnancy from 15% to 2%.
C Anti -D is not of benefit beyond 48 h after a sensitizing event.
D. NOTA
A
Anti-D given to all women who are Rhesus negative will reduce the rate of isoimmunization in a first pregnancy from 1.5% to 0.2%. Anti-D is usually advised to be given within 72 h of an event, including amniocentesis, although some benefit is gained within 9 days.
Prevention of Rhesus haemolytic disease – which of the following are true?
A Anti -D is not of benefit beyond 48 h after a sensitizing event.
B A Kleihauer test at birth will determine whether the dose of anti-D is adequate.
C Anti-D is not indicated if the fetus is known to be Rhesus negative.
D Amniocentesis should be avoided in Rhesus-negative women.
B
Anti-D is usually advised to be given within 72 h of an event, including amniocentesis, although some benefit is gained within 9 days. Anti-D is given after birth and a Kleihauer test is also taken prior to this to ensure this dose has been adequate. Anti-D is not indicated if non-invasive testing has shown the fetus to be Rhesus negative.
