Ed's Get Ahead Specialties SBAs O&G #2 Flashcards
You examine a woman’s abdomen who has attended for induction of labour
at 40 weeks þ 12 days. The abdomen is soft and non-tender. It is difficult to
feel any definite presenting part in the pelvis. The baby is longitudinal lie,
you can feel a smooth part on the patient’s left side and the right side feels
more irregular. The fundus has a ballottable object. You find the fetal heart
above the umbilicus.
How is the position best described?
A. Breech
B. Occipitoposterior
C. Occipitotransverse
D. Occipitoposterior fully engaged
E. Transverse lie
A – Breech
This is a breech presentation for a number of reasons. Firstly, no definite presenting
is felt in the pelvis, as the bottom is softer than the head. The head is felt by
balloting in the fundus of the uterus. The heartbeat is heard above the umbilicus.
The back is on the left where the smoothness was felt and the feet are on
the right where it was more irregular.
Abdominal examination specific to obstetrics
Observe the woman to assess her overall wellbeing. Specifically you are looking
for discomfort, which may suggest labour or abdominal pain, jaundice, itching,
pallor, oedema and an estimate of weight. Observations can be viewed to assess
blood pressure, heart rate and temperature.
For abdominal examination the woman should lie flat in a semi-prone or left
lateral tilt to avoid aortocaval compression. She should be exposed from just
below her breasts to her symphysis pubis.
Inspection is the first stage and you should look for size of the abdomen, striae and
scars. You can often see fetal movements later in pregnancy. Palpation helps
assess liquor volume and how firm/soft the uterus is. You may also feel fetal movements
or contractions if there are any. This will also reveal any uterine tenderness
or irritability. Next feel into the pelvis to look for a presenting part and, if so, if
there is any engagement. Turn to face the pelvis, i.e. with your back to the
woman’s head and use two hands on each side of the uterus at the level of the
umbilicus to gently work your way towards the pelvis with dipping motions in
and out to try to palpate a presenting part. Once you have found a presenting
part try to assess if it is a head or a bottom. A head will feel harder and can generally
be balloted between your hands if it is free. A bottom will feel softer, is
harder to define and cannot be balloted. If you are unsure of the presenting
part, Pawlik’s grip can be used (grasp the presenting part between the thumb
and forefinger). However, this is painful for the woman and should be avoided
if possible. Engagement of the presenting part should be assessed at this point.
This is described in ‘fifths of the head palpable’ abdominally. A head is said to
be engaged if it is less than two-fifths palpable as this describes a position in
which the widest diameter of the head has descended into the pelvis.
A 21-year-old primigravida of 41 weeks gestation rings the labour ward
complaining of gradual-onset abdominal cramping pains approximately
every 15 to 20 minutes. She is concerned as she has had a mucous-like
pink loss vaginally. She has good fetal movements.
What is the most likely explanation for this?
A. Bloody show
B. Cervical ectropion
C. Cervical polyp
D. Placenta praevia
E. Vasa praevia
A – Bloody show
The ‘show’ is a bloody mucus-like loss vaginally that is associated with preparation
for labour. This cervical mucus plug is lost due to pre-labour cervical
changes. Contractions may commence in the following days. If there is any
concern about the amount of bleeding, a speculum examination can be done
to check that there is not excessive bleeding or that the cervix is not dilated.
An 18-year-old girl attends the emergency department with generalized
lower abdominal pains which have been present for a couple of days. She
also complains of a purulent per vagina discharge. She recently had an
intrauterine device inserted as emergency contraception after a condom
she was using failed 3 weeks ago. Currently, she feels hot and sweaty. Her
periods are regular. Observations show a heart rate 96/min, blood pressure
110/70 mmHg and temperature 38.88C. Her abdomen is soft with moderate
tenderness in the lower abdomen. There is no guarding or rebound tenderness.
Speculum examination reveals a purulent discharge. Cervical excitation
was detected on vaginal examination. A urine result is awaited.
What is the most likely diagnosis?
A. Ectopic pregnancy
B. Mittelschmerz
C. Ovarian cyst torsion
D. Pelvic inflammatory disease
E. Urinary tract infection
D – Pelvic inflammatory disease
This girl has pelvic inflammatory disease (PID) – infection of the pelvic organs
from ascending infection through the genital tract, normally via sexual
contact. Common presentations include constant lower abdominal pain, a
purulent discharge per vagina, dyspareunia (pain on intercourse), postcoital
or irregular bleeding, and menorrhagia or dysmenorrhoea. Fever, vomiting,
anorexia and malaise are also seen in women with more severe active infection.
Lower abdominal tenderness, cervical excitation, tenderness on pelvic examination
and pyrexia are seen on examination. High vaginal and endocervical
swabs must be taken and a urine sample should be sent for culture. Immediate
treatment is with antibiotics (e.g. doxycycline and metronidazole), analgesia
and admission to hospital in severe cases. There should be follow-up with
the genitourinary medicine services to enable education, a full sexual health
screen and contact tracing. Complications include tubo-ovarian abscesses,
Fitz-Hugh–Curtis syndrome (perihepatitis leading to perihepatic adhesions),
tubal infertility, ectopic pregnancy and chronic pelvic pain.
A woman is in early labour. The CTG has been reactive with a baseline rate
of 140, multiple accelerations, no decelerations and variability of 15–20.
The trace 30 minutes later shows a baseline rate of 135, with no accelerations
or decelerations and a variability of 5–7 beats.
What could explain the features of this trace?
A. Maternal pyrexia
B. Normal trace
C. Pre-terminal trace
D. Sleep pattern of fetus
E. Thumb sucking of fetus
D – Sleep pattern of fetus
A 44-year-old woman is a regular attendee at the gynaecological clinic. At
her current appointment she complains again of her abdominal pain that
has been present for over 10 years. She says the pain is low in her
abdomen, aching in character with no radiation, associated with nausea,
but with no correlation to her periods. It is worse at night and she finds it
hard to sleep as she is concerned about the pain. She takes no painkillers
as she does not want to put chemicals into her body. She complains of dyspareunia
and is concerned that she may have a sexually transmitted infection
contracted from her husband despite his assurance to her that he has
not been unfaithful. She has previously had two negative diagnostic laparoscopies,
three negative hysteroscopies and multiple negative smear and
swab tests. She is also seeing a neurologist for chronic headaches.
What is the most likely diagnosis?
A. Adhesions from surgery
B. Chronic pelvic inflammatory disease
C. Endometriosis
D. Functional pain
E. Ovarian cysts
D – Functional pain
This woman probably has functional abdominal pain. This can only be a diagnosis
of exclusion once every other pathology has been ruled out. Women must
be told that when investigations are initiated sometimes no cause can be
found for pelvic pain. This can cause resolution of symptoms in some cases
due to the reassurance it provides. If no pathology is found the woman must
be questioned about sexual and social circumstances as there may be an underlying
problem such as relationship difficulties, sexual abuse or fears about
sexuality or fertility. From the information provided in the question it is likely
that relationship difficulties are responsible for the pain. When managing such
cases it is difficult to ensure you do not miss any newly developing pathology.
Conversely, if investigations continue being performed this may reinforce the
concept that there may be something wrong, and the patient may continue
to worry about the pain
Which of the following movement occurs during crowning of the head
during labour?
A. Effacement
B. Extension
C. External rotation
D. Flexion
E. Internal rotation
B – Extension
A 21-year-old woman is asking about contraception, specifically condoms.
How effective are condoms if used correctly?
A. 80% effective
B. 85% effective
C. 95% effective
D. 98% effective
E. 100% effective
Practice
D – 98% effective
Condoms are 98% effective if used correctly which means that two women in
100 will get pregnant in a year. This of course is dependent on age, frequency
of sexual intercourse and correct usage. It is useful to compare this with using
no contraception where 80 to 90 sexually active women out of 100 will
become pregnant in a year.
It is important to discuss advantages and disadvantages of condoms and alternative
forms of contraception. The advantages of condoms are that they are only
used during sexual intercourse, they reduce the risk of some sexually transmitted
infections including HIV, there are no side-effects, they are suitable for
most people and they are easily available. However, the disadvantages are
that putting them on can interrupt sex, there is a risk they can split or slip off,
latex allergy and spillage of semen. Condoms are made less effective if the
penis touches any area close to vagina before application of condom, if the
condom splits or is damaged or slips off or if oil-based products are used
(such as baby lotions) with latex condoms which damage the condoms.
A 37-year-old woman at 17 weeks gestation attends clinic after having had
a triple test result of 1:200. After counselling, she and her partner decide
they need to know definitely whether the pregnancy is affected by
Down’s syndrome.
Which test would be most appropriate?
A. Amniocentesis
B. Chorionic villus sampling
C. Fetal tissue sampling
D. Nuchal translucency test
E. Second trimester ultrasound scan
A – Amniocentesis
The ‘triple test’ uses a number of serum markers, with the age of the mother and
confirmed gestation of the pregnancy to give a ‘risk’ of the fetus having Down’s
syndrome. A ‘positive’ result is said to be anything above a risk of 1 in 250. In
these cases, more invasive testing is offered. The most appropriate next
course of action in this case would be amniocentesis as this will give a definite
diagnosis. Chorionic villus sampling also gives a definite answer but this is preferably
performed between 11–14 weeks, and this woman has already had her
triple test which is performed at 15–16 weeks.
Amniocentesis is known as a diagnostic test as it gives a definite diagnosis rather
than suggesting a risk of a condition. It is performed from 15 weeks gestation as
there is increased risk of miscarriage and talipes if performed earlier. Risk of miscarriage
is 0.5–1%. Amniotic fluid is extracted using a transabdominal needle
under ultrasound guidance. Fetal cells shed from the gut and skin, contained
in amniotic fluid, are cultured for chromosome analysis to be performed. A
full karyotype takes 2–3 weeks; however, polymerase chain reaction (PCR) or
fluorescent in situ hybridization (FISH) can be used for a more rapid result for
a number of conditions such as trisomies, triploidy and Turner syndrome. Indications
for chromosomal analysis include for diagnosis in a positive Down’s
syndrome screening test or for a pregnancy which is known to be high risk of
chromosomal disorders, DNA analysis for genetic diseases, enzyme assays for
inborn errors of metabolism, fetal infection and information about rhesus isoimmunization
via bilirubin. Anti-D is given in RhD negative women.
Second trimester ultrasound scan. Approximately two-thirds of babies with
Down’s syndrome will have normal appearances on an 18-week scan. Minor
defects will be seen on the other one-third but these only show an association
and are not diagnostic. The purpose of this scan is to detect abnormalities in
structural anatomy, measure fetal growth and site the placenta. It can determine
fetal sex with 99% accuracy.
Which of these increases your risk of developing endometrial carcinoma?
A. Combined oral contraceptive pill
B. Early menopause
C. Late menarche
D. Multiparity
E. Obesity
E – Obesity
The majority of uterine cancers arise from the endometrium which is the epithelial
lining of the uterine cavity. It is a single layer of columnar ciliated cells
which form mucus-secreting glands by invaginating into the cellular stroma.
Both the glandular and stromal (supporting) parts of this can undergo malignant
change. Endometrial cancer is the most common cancer of the female
genital tract, occurring most commonly in the over-65s. The majority of
tumours are adenocarcinomas (.90%).
Risk factors include those related to unopposed oestrogen exposure:
† Increasing age – generally found in postmenopausal women, only 5% in
under-40s.
† Obesity – due to the production of oestrogens from peripheral androgens
by aromatization
† Nulliparity
† Early menarche – before age 12
† Late menopause – after age 52
† Unopposed oestrogen therapy – oestrogen-only hormone replacement
therapy
† Tamoxifen – despite having anti-oestrogen properties for breast cancer
it has weak oestrogenic activity on the genital tract.
† Oestrogen-secreting tumours, e.g. granulosa/theca cell ovarian tumours –
although these are rare they are associated with endometrial hyperplasia/
carcinoma in 10% of cases
† Carbohydrate intolerance
† Polycystic ovary syndrome (PCOS) – due to continuous anovulation
therefore unopposed oestrogen
† Personal history of breast or colon cancer
† Family history of breast, colon or ovarian (endometrium type) cancer
The combined oral contraceptive pill, progesterones and pregnancy
are protective. Affected women present with postmenopausal bleeding (in
postmenopausals) and irregular/intermenstrual bleeding or menorrhagia
(in premenopausals).
You consent a woman for a Caesarean section. Which out of the following
would you say was a frequently occurring risk?
A. Bladder injury
B. Hysterectomy
C. Persistent wound and abdominal discomfort in the
months after
surgery
D. Risk of placenta praevia or placenta accreta in subsequent
pregnancies
E. Ureteric injury
C – Persistent wound and abdominal discomfort in the months
after surgery
Whoever gains consent must ensure the patient understands what is being
done, why it is being done, the consequences of having the treatment and
conversely the consequences of not having the treatment and the alternative
treatments to the one being offered. The person gaining consent should understand
the risks in full. Consent for intimate examinations should be recorded
in the notes and performed in the presence of a chaperone. Consent for any
operation should be documented on a formal consent form.
Serious risks for Caesarean section as quoted by the Royal College include
hysterectomy (0.7–0.8%), need for further surgery at a later date (0.5%),
ICU admission (0.9%), bladder injury (0.1%), ureteric injury (0.03%), fetal
laceration (2.0%), increased risk of uterine rupture in subsequent pregnancies
(0.4%), antepartum stillbirth (0.4%) and increased risk of placenta praevia or
accreta in subsequent pregnancies (0.4–0.8%).
Frequent risks include persistent wound and abdominal discomfort in the first
few months following surgery and an increased risk of further Caesarean sections
in future pregnancies. Other procedures that should be documented on
the Caesarean consent form include blood transfusion, repair of bladder and
bowel damage, surgery on major vessels, ovarian cystectomy/oophorectomy
if unsuspected pathology is found and hysterectomy
Ovulation is preceded by 18 hours by a sudden surge in which hormone?
A. Activin
B. Follicle-stimulating hormone
C. Luteinizing hormone
D. Oestradiol
E. Progesterone
C – Luteinizing hormone
Luteinizing hormone is a glycoprotein produced by the anterior pituitary in
response to gonadotrophin-releasing hormones from the hypothalamus.
A 28-year-old woman attends labour ward for induction of labour at
term þ 12. She has some contraction pains but these are mild and she is
not troubled by them. She has had an uncomplicated pregnancy and had
two previous normal deliveries both of which needed inducing due to postmaturity.
The CTG is normal. A scan is done which shows a transverse lie of
the fetus. The cervix is 3 cm dilated.
What would be the next course of action?
A. Artificial rupture of membranes
B. Emergency Caesarean section
C. Oxytocin
D. Prostaglandin
E. Semi-elective Caesarean section
E – Semi-elective Caesarean section
This lady would not be suitable for a normal delivery as the baby is in a transverse
position. She would therefore need a semi-elective section which would be
classified as grade 3 on the RCOG guidelines. Urgency of Caesarean section is
indicated as follows: Grade 1 – immediate threat to the life of the woman or
the fetus; Grade 2 – maternal or fetal compromise which is not immediately
life-threatening; Grade 3 – no maternal or fetal compromise but needs early
delivery; and Grade 4 – delivery timed to suit woman or staff. This would not
be a true elective section of grade 4 as she has started to contract and the
cervix is starting to dilate. It would not be grade 1 or 2 as there is no fetal or
maternal compromise.
Indications for an elective section include:
† Term singleton breech (if external cephalic version (ECV) is contraindicated
or failed)
† Twin pregnancy with breech first twin
† HIV
† Primary genital herpes in the third trimester
† Grade 3 and grade 4 placenta praevia
A Caesarean section should not be routinely offered in:
† Twin pregnancy (if first twin is cephalic at term)
† Preterm birth
† Small for gestational age babies
† Hepatitis B or C infection
† Recurrent genital herpes at term
How long does it take for a single sperm to be created from start to finish?
A. 12 hours
B. 64 hours
C. 12 days
D. 64 days
E. Varies from 12 hours to 12 days
D – 64 days
Spermatogenesis takes place when the adult male reaches puberty and occurs
under the influence of testosterone. The whole process of spermatogenesis
takes 64 days. Primordial germ cells divide by mitosis and differentiate into
spermatogonia, which lie immediately beneath the basement membrane of
seminiferous tubules. As spermatogenesis progresses, the germ cells move
from the basement membrane into the lumen of the seminiferous tubules.
Spermatogonia divide by mitosis and differentiate into primary spermatocytes.
Primary spermatocytes contain 46 double-structured chromosomes. These
divide by meiosis. The primary spermatocytes initially complete the first
meiotic division to give secondary spermatocytes. Secondary spermatocytes
therefore contain 23 double-structured chromosomes which complete
the second meiotic division to give spermatids. Spermatids contain 23 single
chromosomes. Spermatids undergo spermiogenesis (below) to give spermatozoa.
Which of these terms describes a dip in the fetal heart rate of 20 beats per
minute which starts with the contraction and has recovered to normal by
the end of the contraction?
A. Early decelerations
B. Late decelerations
C. Reduced variability
D. Sinusoidal trace
E. Variable decelerations
A – Early decelerations
A 31-year-old woman attends the GUM clinic saying she had unprotected
sexual intercourse with a new partner 3 weeks ago. She reports seeing a
dull red spot on her labia which has now turned into a single, painless,
well demarcated ulcer. She is otherwise well.
What is the most likely diagnosis?
A. Chancroid
B. Granuloma inguinale
C. Herpes simplex
D. Lymphogranuloma venereum
E. Syphilis
E – Syphilis
Treponema pallidum, which is spread by sexual contact, is responsible for
syphilis. Primary syphilis occurs 10 to 90 days after initial infection when a
dull red papule appears on the site of inoculation. It ulcerates to give a single,
painless well-demarcated ulcer known as a chancre. This heals to leave a thin
scar within 8 weeks. Diagnosis is by dark field microscopy from the serum at
the base of the chancre or direct immunofluorescence and serology. The
patient can go on to develop secondary, latent, gummatous and neurosyphilis.
Treatment is with penicillin.
Chancroid is caused by the Gram-negative bacterium Haemophilus ducreyi, and is
found mostly in tropical countries. It is an ulcerative condition of the genitalia
(single/multiple painful superficial ulcers) which develops within a week of
exposure. Inflammation may lead to a phimosis. Enlargement and suppuration
of inguinal lymph nodes may occur, leading to a unilocular abscess (bubo) that
can rupture to form a sinus. Diagnosis is by microscopy and culture. Treatment is
with appropriate antibiotics (e.g. azithromycin).
Lymphogranuloma venereum (LGV) is a sexually transmitted infection caused by
serovars L1, L2 and L3 of Chlamydia trachomatis. It is mainly found in the tropics.
Between 3 and 21 days after infection, one-third of people develop a small painless
papule which ulcerates and heals after days. The patients then develop lymphadenopathy
which is unilateral in two-thirds of cases. Inguinal abscesses
(buboes) may form and develop a sinus. Acute ulcerative proctitis may
develop when infection takes place via the rectal mucosa. Diagnosis is by
culture or serology. Treatment is with tetracycline
A couple who are experiencing difficulties in conceiving are undergoing
investigation. The semen analysis of the male partner reveals asthenospermia.
What does this mean?
A. Complete absence of sperm
B. Localized infection
C. Morphologically defective sperm
D. Poorly motile sperm
E. Reduced sperm count
D – Poorly motile sperm
Male infertility can be due to problems with sperm production, sperm function
or sperm delivery. The quality of sperm can be investigated using semen analysis.
Two semen analyses are needed 3 months apart as sperm count varies and it
takes almost 3 months for spermatogenesis to be completed.
Conditions that may be seen on semen reports are:
Asthenospermia Poorly motile sperm, i.e. lack the normal forward
movement
Azoospermia Complete absence of sperm such as testicular failure
Oligospermia Reduced sperm count of normal appearance
Teratospermia Morphologically defective, with abnormalities of head,
midpiece or tail
Leucospermia Infection
Leucospermia and antisperm antibodies can both be associated with agglutination
and can affect sperm function.
The World Health Organization (WHO) provides reference ranges for semen
analysis (below) although this does not give accurate predictive values about
which man will father a child. This semen analysis only has predictive value
when morphology is below 15% and motility is below 20%.
A 29-year-old primigravida has just given birth to a baby who is unwell and
has had to be taken to the special care baby unit. On examination of the
baby, the paediatricians find dermatomal skin scarring, neurological
defects, limb hypoplasia and eye defects. During the pregnancy the
woman states she had two episodes of vaginal bleeding at weeks 7 and
9. She also states she felt unwell at 14 weeks with a fever and general
malaise followed by an itchy vesicular rash all over her body.
From the description of mother and baby below choose the most likely
infection in pregnancy.
A. Chickenpox
B. Cytomegalovirus
C. Parvovirus
D. Rubella
E. Salmonella
A – Chickenpox
Chickenpox is caused by the DNA varicella zoster virus (human herpesvirus 3)
via airborne spread and direct personal contact with vesicle fluid. There is an
incubation period of 3 to 21 days. There is a prodromal malaise and fever followed
by an itchy rash of maculopapules which become vesicular and crust over before healing. It is infectious 48 hours before the rash appears and until
the vesicles all crust over, which normally takes 5 days. The disease is often
seen in children where a mild infection ensues.
Ninety percent of women are immune due to previous infection. A varicella
vaccine is available and should be considered in women wishing to get pregnant
who are non-immune. Around 3 in 1000 pregnancies are affected. The sequelae
of infection are more serious in pregnant women with a risk of pneumonia
(10%), hepatitis, encephalitis and mortality (1%). Diagnosis is clinical and
treatment supportive with advice to avoid other pregnant women.
Affected women should be offered varicella zoster immunoglobulins within
10 days of exposure if they are not already immune. If chickenpox develops,
she should be advised to avoid other pregnant women and should be given
oral aciclovir if she is seen within 24 hours of the onset of the rash.
The fetus is at risk of developing fetal varicella syndrome, particularly if infection
occurs before 16 weeks, which includes dermatomal skin scarring, neurological
defects, fetal growth retardation, limb hypoplasia, eye defects and hydrops
fetalis
A 35-year-old Afro-Caribbean woman presents with a long history of very
heavy periods. She has visited you now as she cannot cope with the bleeding
and she has a swelling in her abdomen. On examination, you feel a
uterus equivalent to 18 weeks pregnancy; however, she says that she has
not been sexually active for 3 years.
What is the most likely diagnosis?
A. Cervical cancer
B. Cervical ectropion
C. Endometrial carcinoma
D. Large endometrial polyps
E. Uterine fibroids
E – Uterine fibroids
Fibroids (leiomyomata) are whorls of smooth muscle cells interspersed with
collagen. They are benign tumours of the myometrium. Fibroids are present
in 20% of women of reproductive age and are largely asymptomatic. They
are more common in nulliparous and Afro-Caribbean women. They can be multiple
and vary widely in size. Presentation depends on the size and location of fibroids as some are microscopic and others have been known to be 40 kg! The
most common presentation is menorrhagia with intermenstrual bleeding and
abdominal swelling. Pressure on the bladder can lead to frequency of micturition
or hydronephrosis, due to ureteric compression. Other presenting features
include infertility, miscarriage, dyspareunia or pelvic discomfort. Fibroids can be
distinguished on ultrasound as intramural (within the uterine wall), subserous
(beneath the serosal surface of the uterus) or submucosal (beneath the
mucosal surface of the uterus). Treatment is not required if fibroids are asymptomatic.
Medical treatment includes progesterone tablets and gonadotrophinreleasing
hormone analogues. Surgical options include myomectomy (abdominally,
laparoscopically or hysteroscopically), uterine artery embolization and
hysterectomy.
A 23-year-old woman has had two children, one by normal delivery the
other by Caesarean section for fetal distress. She is now in labour. She is
currently 7 cm dilated with membranes intact. The head is low in the pelvis.
Which emergency is she at increased risk of?
A. Cord prolapse
B. Fetal distress
C. Shoulder dystocia
D. Uterine inversion
E. Uterine rupture
E – Uterine rupture
Uterine rupture can occur gradually as labour progresses or more suddenly. A
complete rupture is where the uterine cavity communicates directly with the
peritoneal cavity and the fetus enters the abdominal cavity. This often results
in fetal death (75%) and is life-threatening to the mother due to massive
intra-abdominal haemorrhage particularly if the rupture extends into the
uterine arteries or the broad ligament plexus of veins. Incomplete uterine
rupture is where the uterine cavity is separated from the peritoneal cavity by
the visceral peritoneum of the uterus alone.
Uterine rupture is extremely rare in primigravida and in women who have had
one normal delivery. Increased risk is seen in women with any previous uterine
surgery. There is a 0.6% risk of rupture occurring at the scar site of a previous
Caesarean section in a woman attempting a VBAC (Vaginal Birth After Caesarean).
This risk is increased further if prostaglandins or oxytocin are used. The risk
is increased to almost one-third if the previous section was a classical section
(midline uterine incision rather than the normal lower segment transverse
incision) and most obstetricians would not allow these women to labour,
instead delivering them by elective Caesarean section.
A uterine rupture presents with CTG abnormalities, abdominal pain, maternal
tachycardia, fetal parts being palpable on abdominal examination and
vaginal bleeding (although much bleeding is intraperitoneal). Prior to this
the patient may experience scar tenderness in between contractions, cessation
of contractions, haematuria, vaginal bleeding or evidence of shock from hypovolaemia.
Management is initially the same for any obstetric emergency. Stop any
oxytocin infusion. An immediate laparotomy is needed to deliver the baby
and arrest bleeding. The uterus should be repaired if possible; else an
emergency hysterectomy must be performed.
Which measurement is the most reliable indicator of gestational age after
14 weeks?
A. Amniotic fluid level
B. Biophysical profile
C. Biparietal diameter
D. Crown–rump length
E. Femur length
C. Biparietal diameter
Ultrasound scanning (USS) is a means of monitoring pregnancy and to date is
without proven maternal or fetal risk. Scans can be performed abdominally or
transvaginally.
The biparietal diameter or head circumference is used to date a fetus over
14 weeks. Because the fetus becomes more flexed in shape after this point,
the crown–rump length, which is used before 14 weeks, is less accurate. A discrepancy
of more than 14 days between the estimated delivery date (EDD) from
the scan and last menstrual period (LMP) means the EDD should be changed to
the date acquired from the biparietal measurements rather than from the LMP.
As gestation increases the accuracy of dating the pregnancy by ultrasound
decreases and therefore it is very difficult to give ‘late bookers’ an accurate
EDD which creates problems for planning of induction of labour if spontaneous
labour does not occur by 41 weeks.
The second trimester scan is generally done at 20 weeks as this allows time for a
termination to be planned before 24 weeks if any abnormality is detected and
termination is requested. A detailed fetal structural anatomical survey is performed.
If any abnormality is detected the parents are referred to the fetal medicine
unit. Fetal growth and liquor volume are measured at this scan although it is
very rare that intrauterine growth restriction or oligohydramnios would be seen
this early. If parents wish to know the sex of the baby then most units will
provide this information, however due to misuse of this information by some
cultures it is not offered by all centres. The placental site is determined and if
it is covering or near to the os then a re-scan must be completed at 34 weeks
to exclude placenta praevia
