6. Obs and Gyn Flashcards
What is the most common, and second most common, type of cervical cancer, accounting for 70-80% and 10% of cases respectively?
Squamous cell carcinoma
Adenocarcinoma
In women infected with HPV, what factors increase the risk of it progressing to cervical cancer? (5)
FHx in first degree relative
Oral contraceptive pill use for >5yrs
Smoking
Co-infection with other STIs
High parity and young age at first birth
When is the HPV vaccination given in the uk?
All children 12/13 years old (year 8)
Describe the HPV screening in the UK.
Women age 25-49 are invited for smear test every 3 years.
Women aged 50-64 are invited every 5 years.
Scotland = 25-64 every 5 years
When is the best time to perform cervical screening?
Mid cycle, day 10-20
Risk factors for ovarian cancer:
BRCA1 or BRCA2 mutations
Nulliparity
Late menopause
Early menarche
(All causes of many ovulations)
Which tumour marker is first investigated when ovarian cancer is suspected?
CA125
Should not be used in asymptomatic women
Give 4 conditions that could result in a raised CA125.
Ovarian cancer
Endometriosis
Menstruation
Benign ovarian cysts
What is the definition of pre-eclampsia?
Hypertension developing after 20 weeks gestation with one or more of proteinuria, maternal organ dysfunction or FGR.
State the 5 high-risk factors for pre-eclampsia.
Hypertension in previous pregnancy
Autoimmune condition e.g. SLE, APLS
CKD
T1DM, T2DM
Chronic hypertension
State 6 moderate-risk factors for pre-eclampsia.
First pregnancy
Age >40
Pregnancy interval of >10 years
BMI >35 at first visit
FHx of pre-eclampsia
Multiple pregnancy
To reduce the risk of hypertensive disorders in pregnancy (e.g. pre-eclampsia), two groups of women should take preventative medication. Which groups are these, and what medication should they take?
1 or more high risk factors
2 or more high risk factors
75mg-150mg aspirin daily from 12 weeks until birth
What is the definition of pre-eclampsia?
New onset hypertension >140/90 after 20 weeks gestation and 1 or more of a) proteinuria b) other organ involvement e.g. renal insufficiency, liver, neurological haematological, uteroplacental dysfunction
What is eclampsia?
The development of seizures in association with pre-eclampsia.
Describe the management of eclampsia.
Decision to deliver made.
IV bolus magnesium sulfate of 4g over 5-10 mins, followed by infusion.
Treatment should continue for 24 hours after last seizure or delivery.
What is tocolysis + give drug examples.
Tocolysis is the use of drugs to delay or stop preterm labour.
Terbutaline (beta-adrenergic receptor agonist)
Nifedipine (CCB)
Magnesium sulfate (inhibits entry of calcium into uterine smooth muscle)
Indomethacin (non-selective COX inhibitor, prostaglandin production reduced)
The initiation of labour is still very much a physiological mystery, but appears to be a coordinated inhibition of pro-pregnancy factors and activation of pro-labour factors. Give 4 pro-pregnancy factors and 5 pro-labour factors.
Pro-pregnancy;
Progesterone
Nitric oxide
Catecholamines
Relaxin
Pro-labour;
Oestrogens
Oxytocin
Prostaglandins and prostaglandin dehydrogenase
Corticotrophin releasing hormone (CRH)
Inflammatory mediators
Describe the pro-pregnancy effects of progesterone, including where it is derived from.
Derived from the corpus luteum for first 8 weeks, then the placenta.
Decreases uterine oxytocin receptor sensitivity, promoting uterine smooth muscle relaxation.
Anti-inflammatory role, decreasing cytokine production and influx of immune cells into the myometrium and cervix.
What is the pro-pregnancy role of catecholamines?
Act indirectly on the myometrial cell membrane to alter contractility.
Where is oxytocin produced?
Posterior pituitary gland
What is oxytocin a potent stimulator of?
Uterine contractility.
Unlikely to be a trigger of labour, but increases the frequency and force of contractions.
Describe what happens to oxytocin and oxytocin receptor levels as term approaches.
Receptor levels increase but circulating levels stay the same.
Describe the pro-labour effects of prostaglandins.
Promote cervical ripening and stimulate uterine contractility directly, and by upregulation of oxytocin receptors.
How are prostaglandins synthesised?
Synthesised from arachidonic acid via COX enzymes.
Inflammatory cells are recruited to fetal membranes, uterus and cervix at the onset of labour. Which cytokines are produced and what effects do they have on the pro-labour state?
IL-8, TNF-a, IL-6, IL1B
They contribute to cervical ripening and membrane rupture via increase in collagenase activity.
May also contribute to uterine activity by inhibiting progesterone and activating contractile genes (COX-2, oxytocin r)
The cervix is composed of a network of collagen fibres in ground substance of ECM. How do prostaglandins increase cervical ripening?
Inhibiting collagen syntehsis and stimulating collagenase activity to break down the collagen.
What score is used to assess cervical ripening?
Bishop Score
Describe the 3 stages of labour.
1st stage; onset of labour until full dilatation (of external os)
2nd stage; full dilatation until delivery of baby
3rd stage; delivery of baby until delivery of placenta
Cervical dilatation up to how many cm occurs in Stage 1 of labour?
4cm
What is PPROM?
Preterm pre-labour rupture of membranes
Complications of PPROM (fetal and maternal).
Fetal; prematurity, GBS neonatal infection, pulmonary hypoplasia
Maternal; chorioamnionitis
What should be seen on a speculum exam that confirms PROM?
Pool of liquor in posterior vaginal fornix
Delays in labour can be managed. What is offered when the 1st stage of labour is delayed?
Amniotomy /ARM (artificial rupture of membranes).
Reassess 2 hours later; would expect at least >1cm further dilatation.
Consider oxytocin augmentation.
What options are there for a delay in the 2nd stage of labour?
Must consider cause first; uterine activity, fetal position, maternal and fetal monitoring.
Assisted birth with instrument (forceps, ventouse)
C-section
Oxytocin considered if uterine activity suboptimal
Episiotomy if rigid perineum thought to be cause
Risk factors for ectopic pregnancy (6).
Damage to tubes e.g. PID, surgery
Previous ectopic pregnancy
Smoking
Maternal age over 35
IUD
IVF
Give a typical triad of clinical features of a stable woman presenting with an ectopic pregnancy.
Lower abdominal pain
Vaginal bleeding
Amenorrhoea 6-8 weeks / positive pregnancy test
Give 3 potential examination findings in an ectopic pregnancy.
Abdominal tenderness / distension
Cervical motion tenderness / cervical excitation
Adnexal mass (NICE recommends not palpating for due to risk of rupture)
What is a molar pregnancy?
Slow-growing cystic tumour which develops from trophoblastic cells after fertilisation.
Has abnormal chromosomes; either 2Y from male implants into an ‘empty’ egg, or 3 chr. Abnormal from the start and cannot progress into a normal pregnancy.
Give some differentials of an ectopic pregnancy.
Miscarriage
UTI
PID
Ruptured ovarian corpus luteal cyst
Pregnancy-related degeneration of a fibroid
What is the gold standard investigation for diagnosis of an ectopic pregnancy?
Transvaginal US