NURS 306 Quiz 3 OB 2026 [Latest
Update] | WCU | 100% Verified
Questions & Answers | Grade A
Question 1: Which hormone maintains the corpus luteum during early pregnancy?
A) FSH
B) LH
C) hCG
D) Prolactin
Correct Answer: C) hCG
Explanation: Human chorionic gonadotropin (hCG) produced by the trophoblast binds to LH
receptors on the corpus luteum, sustaining progesterone production until the luteal-placental shift
at ~10 weeks.
Question 2: The normal range for amniotic fluid index (AFI) in the third trimester is
A) 2–5 cm
B) 5–8 cm
C) 8–18 cm
,D) 20–25 cm
Correct Answer: C) 8–18 cm
Explanation: AFI between 8–18 cm is considered normal; values <5 cm indicate oligohydramnios
and >24 cm suggest polyhydramnios, both associated with increased perinatal morbidity.
Question 3: Which maternal serum marker is most elevated in open neural-tube defects?
A) hCG
B) AFP
C) PAPP-A
D) Inhibin-A
Correct Answer: B) AFP
Explanation: Elevated maternal serum alpha-fetoprotein (>2.5 MoM) between 15–20 weeks
suggests leakage of fetal proteins into maternal circulation through exposed membranes in open
NTDs.
Question 4: A G2P1 woman at 28 weeks presents with painless vaginal bleeding. Ultrasound shows
placenta covering the internal os. The most likely diagnosis is
A) Placental abruption
B) Placenta previa
C) Vasa previa
D) Cervical polyp
,Correct Answer: B) Placenta previa
Explanation: Painless bleeding in the third trimester with placenta overlying the cervix is
pathognomonic for placenta previa; digital exams are contraindicated.
Question 5: Which enzyme converts testosterone to estradiol in granulosa cells?
A) 17-α-hydroxylase
B) Aromatase
C) 5-α-reductase
D) 21-hydroxylase
Correct Answer: B) Aromatase
Explanation: Aromatase (CYP19) catalyzes the conversion of androgens to estrogens, essential for
follicular development and endometrial proliferation.
Question 6: Which day is considered the first day of the menstrual cycle?
A) Last day of bleeding
B) First day of full flow
C) First day of spotting
D) Mid-cycle
Correct Answer: B) First day of full flow
, Explanation: Cycle day 1 is defined as the first day of observable menstrual bleeding, used to time
evaluations and interventions.
Question 7: Which phase of the menstrual cycle is most variable in length?
A) Menstrual
B) Proliferative
C) Secretory
D) Ovulatory
Correct Answer: B) Proliferative
Explanation: The follicular/proliferative phase can range from 7 to 21 days, whereas the
luteal/secretory phase is relatively fixed at 12–16 days.
Question 8: Which hormone surge triggers ovulation?
A) FSH
B) LH
C) Progesterone
D) Estrogen drop
Correct Answer: B) LH
Explanation: The mid-cycle LH surge induces final oocyte maturation and follicular rupture within
36–40 hours.
Update] | WCU | 100% Verified
Questions & Answers | Grade A
Question 1: Which hormone maintains the corpus luteum during early pregnancy?
A) FSH
B) LH
C) hCG
D) Prolactin
Correct Answer: C) hCG
Explanation: Human chorionic gonadotropin (hCG) produced by the trophoblast binds to LH
receptors on the corpus luteum, sustaining progesterone production until the luteal-placental shift
at ~10 weeks.
Question 2: The normal range for amniotic fluid index (AFI) in the third trimester is
A) 2–5 cm
B) 5–8 cm
C) 8–18 cm
,D) 20–25 cm
Correct Answer: C) 8–18 cm
Explanation: AFI between 8–18 cm is considered normal; values <5 cm indicate oligohydramnios
and >24 cm suggest polyhydramnios, both associated with increased perinatal morbidity.
Question 3: Which maternal serum marker is most elevated in open neural-tube defects?
A) hCG
B) AFP
C) PAPP-A
D) Inhibin-A
Correct Answer: B) AFP
Explanation: Elevated maternal serum alpha-fetoprotein (>2.5 MoM) between 15–20 weeks
suggests leakage of fetal proteins into maternal circulation through exposed membranes in open
NTDs.
Question 4: A G2P1 woman at 28 weeks presents with painless vaginal bleeding. Ultrasound shows
placenta covering the internal os. The most likely diagnosis is
A) Placental abruption
B) Placenta previa
C) Vasa previa
D) Cervical polyp
,Correct Answer: B) Placenta previa
Explanation: Painless bleeding in the third trimester with placenta overlying the cervix is
pathognomonic for placenta previa; digital exams are contraindicated.
Question 5: Which enzyme converts testosterone to estradiol in granulosa cells?
A) 17-α-hydroxylase
B) Aromatase
C) 5-α-reductase
D) 21-hydroxylase
Correct Answer: B) Aromatase
Explanation: Aromatase (CYP19) catalyzes the conversion of androgens to estrogens, essential for
follicular development and endometrial proliferation.
Question 6: Which day is considered the first day of the menstrual cycle?
A) Last day of bleeding
B) First day of full flow
C) First day of spotting
D) Mid-cycle
Correct Answer: B) First day of full flow
, Explanation: Cycle day 1 is defined as the first day of observable menstrual bleeding, used to time
evaluations and interventions.
Question 7: Which phase of the menstrual cycle is most variable in length?
A) Menstrual
B) Proliferative
C) Secretory
D) Ovulatory
Correct Answer: B) Proliferative
Explanation: The follicular/proliferative phase can range from 7 to 21 days, whereas the
luteal/secretory phase is relatively fixed at 12–16 days.
Question 8: Which hormone surge triggers ovulation?
A) FSH
B) LH
C) Progesterone
D) Estrogen drop
Correct Answer: B) LH
Explanation: The mid-cycle LH surge induces final oocyte maturation and follicular rupture within
36–40 hours.
