D is correct. Bartholin’s glands are located at either side of the vaginal introitus at approximately the junction of the anterior two-thirds and posterior one-third of the vulva. They produce mucus that is drained by the Bartholin’s ducts, which are approximately 2 cm in length and open between the labia minora and the vaginal orifice. Cyst formation is relatively common, but is the result of occlusion of the duct with accumulation of mucus in the duct and not in the gland.
A is correct. The vagina is a tube of smooth muscle lined by non-cornified squamous epithelium. Anteriorly, it is intimately related to the trigone of the urinary bladder and the urethra. Posteriorly, the lower third is separated from the anal canal by the perineal body, the middle third is related to the rectum and the upper third to the rectouterine pouch (pouch of Douglas). The pH of the vagina in the sexually mature non-pregnant female is between 4.0 and 5.0, which has an important antibacterial function in reducing the risk of pelvic infection.
Uterus and its supporting structures:
A is correct. The anterior ligament is a fascial condensation which with the adjacent peritoneal uterovesical fold extends from the anterior aspect of the cervix across the superior surface of the bladder to the peritoneal peritoneum of the anterior abdominal wall. It has a weak supporting role. Likewise, the broad ligament plays only a minor supportive role. Posteriorly, the uterosacral ligaments play a major role in supporting the uterus and the vaginal vault, and these ligaments and their peritoneal covering form the lateral boundaries of the rectouterine pouch (of Douglas).
In pregnancy, the isthmus of the uterus enlarges to form the lower segment of the uterus, which in labour becomes a part of the birth canal but does not contribute greatly to the expulsion of the fetus. (The incidence of uterine retroversion is about 10%.
D is correct. The ovary lies on the posterior surface of the broad ligament in close proximity to the external iliac vessels and the ureter on the lateral pelvic wall. It is attached to the pelvic brim by the suspensory ligament of the ovary. The surface of the ovary is covered by a cuboidal or low columnar type of germinal epithelium. The blood supply is derived from the ovarian artery which arises directly from the aorta. The follicles are found in both the cortex and medulla of the organ.
B is correct. The blood supply to the uterus comes largely from the uterine artery but branches of this anastomose with branches of the ovarian vessels in the upper part of the broad ligament, assuring adequate collateral supply to the uterus even following internal iliac ligation. Lymphatic drainage follows the blood vessels. Uterine pain is mediated through sympathetic afferent nerves passing up to T11/T12 and L1/L2. The pudendal nerve (somatic nerve) supplies the vulva and pelvic floor.)
C is correct. Radiotherapy given in the chest region is unlikely to adversely affect ovarian function (A is therefore incorrect); tamoxifen does not result in ovarian failure, although its use is associated with the development of hot flushes (therefore B is incorrect); cytotoxic chemotherapy given to a child is unlikely to result in ovarian failure and she certainly did not develop this following the treatment of her Wilm’s tumour as she has two children (therefore D is incorrect); and surgery to one ovary is also unlikely to cause a premature menopause (E is therefore incorrect). The cytotoxic chemotherapy given at the age of 36 years is the most likely cause.
Normal follicular growth:
B is correct. In a normal ovulatory menstrual cycle, one follicle is selected to become the dominant follicle on day 5–6 of the cycle (B is therefore correct); however, up to ten show obvious but lesser growth than the dominant follicle (A is therefore incorrect). The dominant follicle grows by 2 mm per day thereafter (C is therefore incorrect), ruptures at about 2 cm in diameter (D is incorrect) and this ruptured follicle becomes the corpus luteum after release of the oocyte (E is therefore incorrect).
C is correct. The seven million germ cells produced during fetal life are produced by mitosis, not meiosis (A is therefore incorrect). The first meiotic division commences in utero in the fetus but ceases in prophase. It does not recommence its division until the luteinizing hormone surge occurs in the particular menstrual cycle and this first meiotic division is completed just prior to fertilization of the oocyte by the sperm (B is therefore incorrect). The attachment of the sperm results in the commencement of the second meiotic division (C is therefore correct). The crossover process between adjacent copies of the same chromosome occurs during prophase of meiosis I, not after meiosis I has been completed (D is therefore incorrect). The long delay between the cessation of prophase I in fetal life and the time when it recommences in the cycle concerned (which can be 40–45 years later) is the reason for the increased incidence of chromosomal abnormalities associated with advanced maternal age (E is therefore incorrect).
Regarding the process of fertilization in the human female:
A is correct. The female gametes only contains an X chromosome therefore cannot determine the sex of the resulting fetus. This is determined by the male gamete which will contain either an X or Y chromosome (B is therefore incorrect). Twin pregnancies occur due to division of the embryo (identical or monochorionic twin pregnancy), or if two separate oocytes are fertilized by two separate sperm (a dichorionic twin pregnancy; therefore C is incorrect). The exact time during which the oocyte can be fertilized after ovulation is uncertain, but it is believed fertilization does not occur if this time interval is in excess of 36 hours (D is therefore incorrect). Sperm capacitation to facilitate fertilization generally occurs within the genital tract of the woman (E is therefore incorrect).
C is correct. Implantation generally occurs five to six days after ovulation and fertilization (A is incorrect) at which time the embryo is at the blastocyst stage (B is therefore incorrect). hCG is produced soon after the implantation process commences (C is therefore correct) and then the plasma levels double every 48 hours if the pregnancy is progressing normally. The endometrium must be secretory in type to allow implantation (D is therefore incorrect) and is then converted to the appearance of decidua. Implantation will not occur if the endometrium is proliferative in type so a pregnancy will not result. Implantation and hCG production can occur even where the embryo is very abnormal, under which circumstances the period occurs at the expected time and the woman concerned never knows she was actually pregnant in that cycle (E is therefore incorrect). A urinary pregnancy test performed 2–3 days after the period commenced will be negative.
C is correct. The blastocyst embeds into the decidua and part of it becomes the placenta which invades into the decidua and into the myometrium and ‘erodes’ into the spiral arterioles to convert them into large lakes to allow maximal perfusion of the placenta. Oxytocin causes uterine contractions and may cause placental separation and hence it does not produce oxytocin but instead it produces oestrogens and progesterones. The placenta is an active organ that produces a number of hormones and needs glucose and amino acids to grow. The placenta helps to transfer the excretory products from the fetal compartment to the mother. It is not richly innervated as there is no specific purpose with such innervation.
Regarding the rise in cardiac output:
D is correct. The rise in cardiac output is seen from early pregnancy. The increase in cardiac output is brought about by increase in the stroke volume and the heart rate. It is associated with a fall in the after load. The heart is already strained due to the need to pump an extra 40% of blood volume and in those with heart disease it can tip the balance and cause heart failure especially if they are anemic or if they contract an infection. The pulmonary vasculature in a mother is able to accommodate the increased blood flow without causing pulmonary hypertension.
Considering respiratory function in pregnancy:
D is correct. Progesterone sensitizes the medulla oblongata and not the adrenal medulla to CO 2 . This causes some over-breathing which reduces the CO 2 level that allows the fetus to offload its CO 2 to the maternal side. Not the maternal P a O 2 but the oxygen carrying capacity of blood increases by 18%. There is an increase in maternal 2,3-DPG that shifts the maternal oxygen dissociation curve to the right, thus facilitating the down-loading of oxygen to the fetus. There is a 40% increase in minute ventilation due to increase in tidal volume from 500 to 700 ml.
Considering renal function in pregnancy:
C is correct. There is increase in renal size of up to 70% due to increase in size of the parenchyma in addition to the enlargement of the pelvicalyceal system and the ureter, but the increase is seen from early pregnancy. The ureters increase in size due to the influence of progesterone and increased urinary output but they are not floppy and have good tone. Because of an increase in blood volume there is a 50% increase in GFR that activates the renin angiotensin system. About 900 and not 1800 mmol of sodium are retained during pregnancy. Because of ureteric dilatation and reflux of urine due to lack of sphincteric action at the point entry of ureter into the bladder and higher incidence of urinary stasis there is higher incidence of urinary tract infection in pregnancy.
In relation to endocrine function in pregnancy:
A is correct. Insulin resistance develops with progress of pregnancy due to the change in the hormonal milieu. There is a significant increase in human placental lactogen after 28 weeks as a result of which some women develop gestational diabetes. Due to increased glomerular filtration rate, more glucose is presented to the kidneys and in some mothers the quantity of glucose exposed for absorption exceeds the tubular maximal absorption capacity and hence presents as ‘renal’ glycosuria without a high blood glucose level. Because of increased metabolism, the thyroid increases in size. The gut absorbs more calcium but more is also lost in the urine and in areas of dietary deficiency, calcium supplementation becomes necessary. Skin pigmentation is caused by an increase in melanocyte secreting hormone.
In early placental development:
D is correct. The villi have inner cyto and outer syncytiotrophoblast that invades the endometrium and myometrial layers. Decidual cells provide the initial nutrition for the invading trophoblasts. The spiral arterioles are invaded by the trophoblasts making large lacunae that are full of maternal blood and the tertiary villi bathe in these lacunae to accomplish the respiratory, nutrition and excretory functions. Chorion frondosum forms the placenta. Chorion laevae is the layer surrounding the membranes and it fuses with the uterine cavity.
Regarding the umbilical cord:
C is correct. The umbilical cord has two arteries and one vein. The fetus pumps the blood through these arteries to the placenta to get more oxygen and excrete the carbon dioxide and hence arterial blood has less oxygen compared with the vein. One in 200 babies has only one artery and one vein and they grow normally and live birth is achieved. Cord arterial pressure is 70 mmHg and the venous pressure is 25 mmHg. The relative venous pressure is higher to maintain good venous circulation that is vital to bring oxygen and nutrition to the fetus.
A is correct. Simple diffusion is according to the concentration gradients and this facilitates transfer of oxygen and carbon dioxide in the right direction for the fetus. Glucose is transferred according to the gradient but it needs energy i.e. facilitated diffusion. Active transport needs energy for transport and to drive the substances against the gradient and hence there could be cases where the concentration may be already higher in the fetal blood. Higher molecular weight substrates are transferred by pinocytosis. Fetal cells escape into the maternal circulation due to the higher pressure on the fetal side and due to breaches in the fetomaternal barrier.
E is correct. The placenta has multiple functions. It helps with gas exchange and is an important organ for transferring nutrition to the fetus and excretion of waste products from the fetus. It produces a number of hormones; initially human chorionic gonadotrophin and later oestrogens and progesterones, which are all essential for maintenance of pregnancy. But it is a poor barrier against infections thus the fetus is affected by malaria, syphilis, HIV, CMV and toxoplasmosis.
A is correct. Polyhydramnios may suggest fetal anomaly such as neural tube defects, anencephaly, gut atresia and several other known pathologies. Aminocentesis carries a risk of miscarriage, pre-labour rupture of membranes, infection and preterm labour although these are less than 1%. Postural deformities are one of the complications of long-standing severe oligohydramnios. A major problem with this situation is pulmonary hypoplasia. Adequate fluid is needed to push the alveoli and bronchioles to expand; if not it results in lung hypoplasia. Most cases of intrauterine growth restriction would be associated with reduced amniotic fluid due to less urine production caused by less renal perfusion. Amnio-infusion may abolish the variable decelerations but trials have shown no improvement in clinical outcome and hence it is not a standard procedure.
C is correct. Perinatal mortality rate describes the number of stillbirths and early neonatal deaths per 1000 total births (live births and stillbirths). This gives a picture of maternal health and the standard of care provided to mothers and their newborn babies. By improving socioeconomic conditions, the quality of obstetric and neonatal care and an active screening programme for common congenital abnormalities, perinatal mortality rates can be significantly improved. The World Health Organization has two targets for assessing progress in improving maternal health (MDG 5). These are reducing maternal mortality ratio by 75% between 1990 and 2015, and achieving universal access to reproductive health by 2015.
E is correct. Until 2011, the Centre for Maternal and Child Enquiries has published annual perinatal reports for the UK. The report showed a significant reduction in both stillbirth rates and early neonatal deaths. Stillbirth rates indicate the quality of antenatal care and screening programmes and are the largest contributors to perinatal mortality. Most stillbirths occur antenatally. The traditionally used systems such as the Wigglesworth and the Aberdeen (Obstetric) classifications consistently reported up to two-thirds of stillbirths as being from unexplained causes. The sub-Saharan regions of central Africa have the highest stillbirth rates.
Regarding neonatal deaths:
B is correct. Birth weight is no doubt an indication of maternal health and nutrition. Neonatal tetanus remains a common cause of neonatal death in settings where lack of hygiene and inadequate cord care are prevalent, as many women are not immunized against tetanus. The majority of deaths from neonatal tetanus occur between the tenth day of life. Prematurity remains a significant contributor to perinatal mortality rates in developing countries and improving maternal health and obstetric care are more important steps to improving the outcome than to provide for more neonatal intensive care units.
Regarding the description of maternal deaths:
A is correct. Direct maternal deaths are defined as those resulting from conditions or complications or their management that are unique to pregnancy, occurring during the antenatal, intrapartum or postpartum periods. Coincidental (fortuitous) deaths occur from unrelated causes which happen to occur in pregnancy or the puerperium. Definitions of maternal death can vary across the regions and between countries. As the UK has the advantage of accurate denominator data, including both live births and stillbirths, it has defined its maternal mortality rate as the number of direct and indirect deaths per 100,000 maternities as a more accurate denominator to indicate the number of women at risk. Maternities are defined as the number of pregnancies that result in a live birth at any gestation or stillbirths occurring at or after 24 completed weeks of gestation and are required to be notified by law. Improving the socioeconomic status of women coupled with improved maternal health and antenatal care are key to the improvement of maternal mortality rates.
D is correct. In the 2006–2008 UK Confidential Enquiry into Maternal Deaths Report, the leading cause of direct deaths was sepsis, particularly from Group A Streptococcus. This infection can occur at any time during the antenatal or postpartum period and the onset can be insidious and non-specific. Cardiac diseases remained the leading cause of indirect deaths. The reduction in the number of deaths from venous thromboembolism is due mainly to improved screening and thromboprophylaxis guidelines adopted by all maternity units in the UK. However, it remains an important and avoidable cause of death.
Basic clinical skills in obstetrics:
E is correct. Correct, compassionate verbal and non-verbal communication is an essential skill in clinical medicine. This includes introduction of the care provider, proper identification of the woman, expression of the purpose of the clinical examination and detailed history taking. This is followed by good general, systemic and obstetric examination. Any deviation from the norm should be noted and discussed with the woman including a diagnosis or differential diagnosis. Performing a fetal anomaly scan is an advanced skill and is practiced only by who had sufficient training.
In eliciting an obstetric history:
E is correct. Past obstetric history is pivotal to managing the index pregnancy, e.g., past history of diabetes, hypertensive or psychiatric illness would help us to plan management better. Many women do not remember the LMP accurately and when facilities permit the gestation is assessed by ultrasound in the first trimester and EDD is calculated based on the early scan. Post-ovulatory period is fairly constant and is about 14 days whether the cycle is long or short. Ultrasound for dating can be three weeks + or − if it is based on third trimester scans, while its + or − 1 week if it is based on a first trimester scan. Hormonal contraception may delay the first ovulatory cycle after discontinuation of the method.
Regarding symptoms of pregnancy:
E is correct. Nausea and vomiting can start within two weeks of missed period and it is believed to be secondary to the rise of human chorionic gonadotrophin (hCG). The frequency of micturition is due to the increased urine production due to increased glomerular filtration rate following 40% expansion of the blood volume in addition to the pressure on the bladder by the gravid uterus. This pressure is relieved after 12 weeks when the uterus becomes an intra-abdominal organ hence the frequency lessens. Morning sickness fades away when the pregnancy progresses to the second trimester and only in a minority of cases it may continue throughout pregnancy. Plasma osmolality reduces with advancing gestation due to increased intravascular volume and reduced plasma proteins. There is increased diuresis after water loading when the woman is sitting in an upright position, perhaps due to increased perfusion.
C is correct. Blood pressure (BP) is recorded when the patient is sitting up or lying at a 45° incline and not whilst she is lying on her back because the venous return may be reduced, affecting the cardiac output and the reading. BP should be recorded in the same position during each visit using an appropriate size cuff – obese women would need a larger cuff. If inferior venacaval compression is prolonged it is likely to affect the cardiac output of the mother and hence the uterine circulation, which could compromise the baby. Current recommendation is to consider the Korotokoff fifth sound and if the point at which the sound disappears cannot be identified, then use the Koratokoff fourth sound. The flow murmurs are of no significance and should be differentiated from any murmur due to a cardiac pathology.
In pelvic examination during pregnancy:
B is correct. With the availability of first trimester scanning, it is not essential to perform a routine pelvic examination. When there is painless bleeding in late pregnancy, placenta praevia should be excluded. Digital vaginal examination in cases of placenta praevia may cause torrential haemorrhage and require an emergency caesarean section, hence it is contraindicated. Radiological examination of the pelvis is of little value in predicting labour outcome as labour is a dynamic process with changes in dimensions occuring with flexion of the baby’s head and moulding and pelvic give. The gynaecoid pelvis is ‘roomy’ at all levels of the pelvis to allow cephalic descent. The diagonal conjugate is only 1.5 cm longer than the obstetric diameter.
Regarding antenatal screening for infection:
B is correct. Screening for Hepatitis B is routinely carried out. Hepatitis B is easily transmitted to the fetus and newborn whist it traverses the birth canal. If the mother has hepatitis B antibodies, further testing is required to confirm if they are positive for surface (s) antigens or core (e) antigens. Those who are positive for core antigens are considered to have active viruses and may have a high transmission rate of up to 85% to the fetus. In most countries newborns are given gamma globulins and the active vaccine if e positive and only the vaccine if they are s positive. If the infection is transmitted there is a high possibility of liver cirrhosis followed by hepatocellular cancer, hence the need to actively immunize the newborn. No routine screening is done for cytomegalovirus (CMV) as reinfection is not uncommon and no preventive action can be taken based on the test. General advice should be given to avoid child nurseries where children have coughs, colds and influenza and may harbour CMV infection that is easily transmitted. Syphilis is uncommon but if detected it is eminently treatable to avoid infection of the fetus and its sequelae. Checking the husband/partner and contact tracing is important. Rubella infection causes major congenital malformations in 25–50%, if the mother is infected in the first trimester of pregnancy. If the mother is not immune she should be immunised postpartum. HIV/AIDS screening is not universal but it is advisable to make it as a routine screening. If found positive, antiretroviral therapy, elective caesarean delivery and avoidance of breast feeding has reduced the incidence of vertical transmission from 45% to less than 2%.
Group B streptococcus:
C is correct. Group B streptococcus is a Gram-positive bacterium and is a commensal organism found in the nose, oropharynx, nasopharynx, anal canal and vagina. Group B streptococcal colonization of the genito-urinary tract is associated with higher incidence of preterm labour and pre-labour rupture of membranes. Screening is not routine in all the countries. In the UK screening is not performed but should there be a high risk history, then suitable precautions are taken, especially intrapartum penicillin therapy if the mother had streptococcal colonization in the vaginal or rectal swab or growth in urine culture.
E is correct. Gestational diabetes predisposes to macrosomic babies and those who had higher birth weight babies in the previous pregnancy are more prone to gestational diabetes. The cut off value of when to consider the baby to be macrosomic, i.e., >4 or 4.5 kg varies with population studied. Maternal BMI >35 has a known association with gestational diabetes mellitus in pregnancy. Gestational diabetes in previous pregnancy identifies those who are likely to develop early onset type II diabetes in their life and they also indicate a higher chance of getting gestational diabetes in subsequent pregnancies. Older mothers >35 years of age are more prone to gestational diabetes and not younger mothers.
Extra folic acid supplementation:
E is correct. Folic acid is well known to reduce the overall incidence of congenital malformations. Folic acid facilitates cell division and is an important vitamin in any growth or reparative process. Extra folic acid supplementation (5 mg per day) reduces neural tube defects and hence it is important to take prior to and in early pregnancy in mothers who had a previous child with neural tube defects. Mothers who have epilepsy, especially those who are on anti-epileptic medication, have a higher chance of having children with neural tube defects and they should be advised on higher dose folic acid supplementation. This also applies to mothers with diabetes and those with a high BMI, e.g., >35. Downs syndrome is a chromosomal problem, commonly trisomy 21, and the incidence cannot be reduced by taking extra folic acid.
C is correct. Moderate exercise for recreation, including swimming, is harmless and is encouraged. Strenuous exercise and competitive sports with active movements are contraindicated. Coitus does not do any harm although there may be release of prostaglandins with the semen. If the mother has threatened miscarriage, abdominal pain, bleeding, short cervix or threatened preterm labour it may be unwise to participate in coitus. There is controversy about minimal alcohol consumption and its effects on the fetus. Moderate alcohol consumption may be harmful to the fetus and severe alcohol consumption is associated with fetal alcohol syndrome associated with microcephaly and mental retardation. Smoking is harmful to the pregnancy and is well known to be associated with intra-uterine growth restriction. Paracetamol is safe in pregnancy. Non-steroidal anti-inflammatory drugs taken in significant amounts in the third trimester may cause oligohydramnios and premature closure of the ductus arteriosus.
Antepartum haemorrhage at 36 weeks:
C is correct. Although placental abruption (separation of normally situated placenta) and placenta praevia (low lying placenta) are major causes of maternal and perinatal morbidity and mortality the incidence of each of these conditions is less than 1%. The commonest reason is idiopathic. Clinical examination both general, abdominal and a speculum examination (to exclude cervical or vaginal lesion and to visualize whether blood is emerging via the cervical os) and an ultrasound examination (to check the placental position and to visualize the fetal lie and presentation and liquor volume) are vital to identify the other causes and to come to the diagnosis by exclusion of ‘idiopathic’.
Hypertension in pregnancy:
D is correct. In modern practice the fifth Korotkoff sound is used to determine diastolic blood pressure. More emphasis is now paid on systolic reading especially that >160 mmHg as there is a greater tendency for cerebral hemorrhage and there is strong recommendation to immediately treat and bring the systolic BP <150 mmHg and preferably <140 mmHg. Hypertension after 20 weeks is gestational in the absence of proteinuria and the diagnosis would be pre-eclampsia in the presence of significant proteinuria. There are several factors that may be contributory to a rise in blood pressure although it is known that there is a fall in peripheral resistance due to vasodilatory hormones including oestrogen and progestorone. In pre-eclampsia the vasoconstrictor thromboxane and vasodilatory prostacyclin mainly liberated by the platelets and endothelial cells of blood vessels play a major role. HELLP syndrome stands for haemolysis, elevated liver enzymes and low platelets and it signifies a serious form of the pre-eclamptic process which has affected several systems. It has a poor prognosis and careful management and early delivery is advised.
B is correct. The prevalence of identical twins appear to be uniformly similar in many countries. Twin peak sign or lambda sign at the attachment of the membranes to the uterus signifies additional chorionic layers in-between the amniotic membranes and the diagnosis of dizygotic twins. All complications of pregnancy are increased in twins and miscarriage is not an exception. Preterm delivery in twins is twice that of singleton pregnancy and the average gestational age of delivery of the fetuses are much less than singletons. Twin-to-twin transfusion can appear as early as 18 weeks and many centres would scan at this stage and decide on the date of the next scan. Earlier diagnosis and treatment by laser transection of anastomotic vessels is associated with better outcome.
The causes of an unstable lie:
D is correct. Placenta praevia occupies the lower segment and prevents the head or breech from settling down in the pelvis. Polyhydramnios allows the fetus to ‘float’ around instead of binding the fetus to a longitudinal lie by the uterine muscular tone and normal amount of amniotic fluid volume. Subseptate uterus limits the space of the uterine cavity and some fetuses may present with transverse or oblique lie. Primiparity is generally associated with good uterine and abdominal muscle tone and should favour a stable longitudinal lie. In twin pregnancy the first twin usually presents in the longitudinal lie but the second twin can be in an abnormal lie and the incidence is made greater if it is associated with polyhydramnios.
C is correct. Post-maturity syndrome has no direct link to prolonged pregnancy. Post-maturity syndrome describes a newborn which is growth retarded, has an anxious look, is stained with meconium, and has overgrown nails and peeling skin on the palm and sole. Mother’s recollection of menstrual period is shown to be incorrect in >20% of cases. There is a possibility of fetal anomaly like anencephaly and this should be excluded. Prolonged pregnancy is associated with perinatal morbidity and mortality. The guidelines from most recognized professional bodies suggest induction by 41 weeks and three days to avoid morbidity and mortality based on the evidence from randomized controlled studies.