1. Which of the following tests can be used to assess the risk of preterm delivery?
A. Human chorionic gonadotropin (hCG) in serum
B. Fetal fibronectin in the cervical or vaginal fluid
C. Luteinizing hormone (LH) in urine
The correct answer is B. Fetal fibronectin is produced by fetal membranes and appears in the cervix and vagina early in pregnancy as implantation develops, and normally disappears by week 20. Its reappearance in the third trimester often precedes labor and delivery.
2. Which one of the following choices is not a component of the quadruple screen for Down syndrome, used as a second-trimester screen for the syndrome?
The correct answer is A. Nuchal translucency is in the first-trimester screen along with free β-hCG and pregnancy-associated plasma protein A. The quadruple screen includes AFP, hCG, unconjugated estriol, and inhibin A.
3. Hemolytic disease of the newborn is a syndrome in which the newborn becomes anemic from the destruction of his/her red blood cells in utero. This red blood cell destruction is a result of maternal IgG antibodies formed against a red blood cell antigen. Which of the red blood cell antigens below is most commonly associated with hemolytic disease of the newborn?
The correct answer is C. Antibody production by a mother who is Rh negative results from exposure of Rh-positive fetal cells during pregnancy and, to a much greater extent, at delivery. Therefore, the women at greatest risk for delivering infants with hemolytic disease of the newborn are Rh-negative mothers who conceive Rh-positive babies, and are in the second or subsequent pregnancies.
4. Which of the following tests is less commonly used than the others to evaluate a patient for cystic fibrosis?
B. Immunoreactive trypsinogen
C. Mutational analysis of the membrane chloride channel known as CFTR
The correct answer is D. The sweat chloride test is a screening test for cystic fibrosis for patients of all ages. The test for immunoreactive trypsinogen is ...