OBG MCQs with Answers
1 With regard to the obstetric history:
a) Pregnancy is dated from conception.
b) Parity is the total number of pregnancies regardless of how they ended.
c) It is recommended that women should be seen on their own at least once.
d) A family history of pre-eclampsia should trigger increased antenatal surveillance.
e) The last menstrual period is reliable if the cycles are irregular.
Answer
C and D
Explanation:
Pregnancy is dated from the last menstrual period. Gravidity is the total number of pregnancies regardless of how they ended. Domestic violence is an increasing problem and it is recommended that all women are seen on their own to discuss this potential problem. A family history of pre-eclampsia increases the risk pre-eclampsia in this pregnancy.
2 The following terms are appropriate:
a) Lie: cephalic.
b) Position: flexed.
c) Station: at the level of the spines.
d) Engagement: two-fifths.
e) Presenting part: shoulder.
Answer
C, D, E
Explanation:
Cephalic describes presentation and not lie. The shoulder presents with a transverse lie.
3 Maternal mortality:
a) Includes death caused by an ectopic pregnancy.
b) Is subjected to a confidential enquiry.
c) Must be reported to the Coroner.
d) Epilepsy is the commonest cause of indirect maternal death.
e) Is most often caused by sepsis.
Answer
A and B
Explanation:
Maternal death is defined as the death of a woman while pregnant or within 42 days of termination of pregnancy, from any cause related to or aggravated by the pregnancy or its management, but not from accidental or incidental causes. The commonest indirect cause of maternal death is cardiac disease, with suicide as the next most common. The commonest cause of maternal death on the last confidential enquiry was thromboembolic disease.
4 Confidential Enquiry into Stillbirths and Deaths in Infancy (CESDI):
a) Includes only deaths after 24 weeks.
b) Late neonatal deaths occur after the first month of life.
c) The principal cause of death in the last CESDI was congenital abnormality.
d) Was set up to investigate suboptimal medical care.
e) Perinatal death: all stillbirths plus deaths in the first week of life.
Conception, implantation and embryology
Answer
D and E
Explanation:
CESDI applies to deaths after 20 weeks’ gestation. The definition of late neonatal is death from 7 to 27 completed days after delivery. The principal cause of fetal death is prematurity and not congenital abnormality. The report classifies cases according to the type of care that they received.
5 During development of the ovarian follicles:
a) The primary oocyte is arrested at the interphase of the second meiotic division.
b) Granulosa cells in the corpus luteum are responsible for steroidogenesis.
c) Theca cells produce testosterone from cholesterol.
d) Meiosis is resumed prior to the luteinizing hormone (LH) surge.
e) The first polar body is extruded prior to ovulation.
Answer
B, C and E
Explanation:
The primary oocyte is arrested at the metaphase of the second meiotic division and not the interphase of the cycle. Meiosis is not resumed until after the LH surge. The first polar body is extruded prior to ovulation and the second polar body is extruded after ovulation.
6 After a successful conception the following statements are true:
a) The embryo remains in the fallopian tube for 6–8 days.
b) Myometrial cytokines modulate cytotrophoblastic proteolytic activity.
c) At 11 days the implantation site can be seen as a red spot on the endometrial mucosa.
d) Human chorionic gonadotrophin is produced by the corpus luteum.
e) The embryonic disc is formed after the third week postfertilization.
Answer
C
Explanation:
The embryo after fertilization remains in the fallopian tube for 3–4 days. It is endometrial cytokines not myometrial cytokines that modulate cytotrophoblastic proteolytic activity to control the depth of invasion. Human chorionic gonadotrophin is produced by the trophoblast; therefore, it is a specific indicator of pregnancy. It can also be utilized in the diagnosis of ectopic pregnancy. The embryonic period starts with the generation of the embryonic disc during the second week postfertilization.
7 Considering embryo development:
a) During the third week, the bilaminar embryo generates the mesoderm.
b) At day 28, the cephalic neuropore closes.
c) Cardiac activity is evident from day 26.
d) The lower respiratory system appears as septation of the foregut.
e) The fetus is recognizably human at 12 weeks’ gestation.
Answer
A, D and E
Explanation:
The cephalic neuropore closes during the 26th day and the caudal neuropore on the 28th day after fertilization. Cardiac activity is evident from day 22.
8 In normal pregnancy:
a) Blood pressure falls in the second trimester.
b) Plasma volume decreases throughout gestation.
c) There is a reduction in erythrocyte production.
d) 50 per cent of women have a transient diastolic murmur.
e) There is an increase in the number of polymorphonuclear leucocytes.
Answer
A and E
Explanation:
The plasma volume increases in pregnancy until around 32 weeks after which time it plateaus. The increase in the plasma volume is one of the fundamental physiological changes of normal pregnancy. This change is essential to other physiological changes that occur during pregnancy,which include increased cardiac output and an increase in renal blood flow. Erythrocyte production is increased in pregnancy; however, there is marked dilution of red cells in the blood owing to the increased plasma volume. The maternal heart sounds change during pregnancy: there is an increased loudness in both s1 and s2, >95 per cent of women develop a systolic murmur that disappears after delivery, and 20 per cent have a transient diastolic murmur.
9 Maternal effects on the physiology of the kidney include:
a) There is a 40 per cent increase in renal blood flow.
b) There is an increase in the glomerular filtration rate.
c) The urea and creatinine are higher than the non-pregnant state.
d) The upper limit of protein excretion in pregnancy is 0.6 g per day.
e) The kidneys increase in size.
Answer
B and E
Explanation:
During pregnancy, there is a dramatic (60–75 per cent) increase in the renal blood flow. The consequence of this is an increase in the glomerular filtration rate (GFR) of the kidney. The increase in the GFR is responsible for an increase in the clearance of urea and creatinine. Thus plasma concentrations of urea and creatinine are reduced during pregnancy. Kidneys increase in length by approximately 1 cm during pregnancy.
10 During lung development:
a) Alveolar development occurs after 20 weeks.
b) The predominant phospholipid is phosphatidylcholine.
c) Fetal lung fluid production ceases in the second stage of labour.
d) Fetal breathing movement occurs for 30 per cent in the second trimester.
e) The production of lecithin is enhanced by cortisol and diabetes.
Answer
B
Explanation:
The fetal alveoli start to develop after 20 weeks’ gestation. The predominant phospholipid is phosphatidylcholine (lecithin). The production of lecithin is enhanced by cortisol, growth restriction and prolonged rupture of membranes.However, diabetes mellitus delays the production of respiratory lecithin. The fetal lung is filled with fluid from an early gestation. Its production ceases in the early stages of labour under the influence of adrenaline.
11 With regard to routine antenatal care:
a) There is no evidence in low-risk pregnancies that reduction in antenatal visits increase maternal or fetal mortality.
b) The Naegele rule states that the expected date of delivery (EDD) is calculated by adding 7 days to the last menstrual period (LMP) and then taking away 4 months.
c) Syphilis testing forms part of the routine booking visit.
d) Routine urine testing reduces preterm labour.
e) Every patient should have a named consultant.
Answer
A and C
Explanation:
The Naegele rule states that the EDD is calculated by adding 7 days to the LMP and then taking away 3 months. However, this rule assumes a 28-day cycle and ovulation on day 14, and finally an accurate recollection of the LMP. Although only a small number of women are diagnosed with syphilis during pregnancy, the vertical transmission to the fetus has serious consequences. This transmission to the fetus can easily be prevented by treatment of the mother with antibiotics. There are several classifications of antenatal care; if the women have community care, then the lead clinician would be the community midwife.
12 The routine dating scan:
a) Allows accurate dating of the pregnancy and a reduction in induction of labour for prolonged pregnancy.
b) Allows the detection of placenta praevia.
c) Allows early detection of twin pregnancies.
d) Allows detection of a failed pregnancy.
e) Allows detection of uterine abnormalities.
Answer
A, C, D, E
Explanation:
The routine dating scan is unable to detect placenta praevia. Placenta praevia can be detected by ultrasound but not until the third trimester.
13 Regarding diagnostic ultrasound:
a) It employs the use of low-frequency, high-intensity sound waves.
b) Between 12 and 20 weeks, the crown–rump length and femur length are the most reproducible assessment
of gestational age.
c) It can be used to determine chorionicity accurately in twin pregnancy at the 20-week scan.
d) It has shown that an increased nuchal translucency is associated with cardiac defects.
e) In 6 per cent of pregnancies, there will be a serious fetal structural abnormality.
Answer
D
Explanation:
The technique of ultrasound utilizes high-frequency, low-intensity sound waves to generate an image. Fetal age can be assessed accurately prior to 12 weeks by measuring the crown–rump length and from 12 to 20 weeks gestation can be determined from biparental diameter. The chorionicity of twin pregnancy is best determined in the first trimester; this should ideally occur at approximately 12 weeks. Nuchal translucency has been shown to be a screening test for Down’s syndrome, other chromosomal abnormalities and cardiac defects. Serious fetal structural abnormalities are diagnosed in 3 per cent of all pregnancies.
