OB-GYN Revision 3 Flashcards
What nutritional supplements should be given and when? [2]
Folic acid - 400mcg
- before conception until 12 weeks
Folic acid 5mg if:
- Maternal coeliac or DM, obese, relative w/ NTD or epilepsy
Vitamin D
- daily supplement containing 10micrograms of vitamin
NB cases with need higher Folic acid: MORE - Maternal disease, Obese, Relative w/ NTD; Epilpesy
What advise would you give about air travel during pregnancy? [3]
- women > 37 weeks with singleton pregnancy and no additional risk factors should avoid air travel
- women with uncomplicated, multiple pregnancies should avoid travel by air once >32 weeks
- associated with increased risk of venous thromboembolism
- wearing correctly fitted compression stockings is effective at reducing the risk
Why are NSAIDs generally not prescribed in pregnancy? [2]
Prostaglandins are important in maintaining the ductus arteriosus in the fetus and neonate
Prostaglandins also soften the cervix and stimulate uterine contractions at the time of delivery
Therefore
- They are particularly avoided in the third trimester, as they can cause premature closure of the ductus arteriosus in the fetus.
- They can also delay labour.
What affect can beta blockers have if given during pregnancy? [3]
Which beta-blockers are used if neeed? [1]
Beta-blockers can cause:
* Fetal growth restriction
* Hypoglycaemia in the neonate
* Bradycardia in the neonate
Labetalol is the most frequently used beta-blocker in pregnancy, and is first-line for high blood pressure caused by pre-eclampsia.
What is the affect of of ACEin or ARBs in pregnancy? [4]
- Oligohydramnios (reduced amniotic fluid)
- The other notably effect is hypocalvaria, which is an incomplete formation of the skull bones.
- Renal failure in the neonate
- Hypotension in the neonate
- Miscarriage or fetal death
What affect can opiates cause if given during pregnancy? [1]
The use of opiates during pregnancy can cause withdrawal symptoms in the neonate after birth. This is called neonatal abstinence syndrome (NAS).
NAS presents between 3 – 72 hours after birth with irritability, tachypnoea (fast breathing), high temperatures and poor feeding.
Warfarin is considered teratogenic in pregnancy, therefore it is avoided in pregnant women. Warfarin can cause [3]
- Fetal loss
- Congenital malformations, particularly craniofacial problems
- Bleeding during pregnancy, postpartum haemorrhage, fetal haemorrhage and intracranial bleeding
The use of sodium valproate in pregnancy causes [] and []
The use of sodium valproate in pregnancy causes neural tube defects and developmental delay.
Lithium is particularly avoided in the [] trimester, as this is linked with congenital [] abnormalities.
- In particular, it is associated with [] anomaly
Lithium is particularly avoided in the first trimester, as this is linked with congenital cardiac abnormalities
- In particular, it is associated with Ebstein’s anomaly
Lithium is associated with Ebstei’s anomaly.
Describe what this is [1]
where the tricuspid valve is set lower on the right side of the heart (towards the apex), causing a bigger right atrium and a smaller right ventricle.
Women need to be aware of the potential risks of SSRIs in pregnancy.
What are they? [4]
First-trimester use has a link with congenital heart defects
* First-trimester use of paroxetine has a stronger link with congenital malformations
Third-trimester use has a link with persistent pulmonary hypertension in the neonate
Neonates can experience withdrawal symptoms, usually only mild and not requiring medical management
Describe in detail the first stage of labour
Include the different phases of the first stage of labour [3]
First stage: from the onset of labour until the cervix is fully dilated to 10cm
It involves cervical dilation (opening up) and effacement (getting thinner from front to back)
The “show” refers to the mucus plug in the cervix, that prevents bacteria from entering the uterus during pregnancy, falling out and creating space for the baby to pass through.
Phases of the first stage:
Latent phase:
- From 0 to 3cm dilation of the cervix.
- This progresses at around 0.5cm per hour. There are irregular contractions.
Active phase::
- From 3cm to 7cm dilation of the cervix.
- This progresses at around 1cm per hour, and there are regular contractions.
Transition phase:
- From 7cm to 10cm dilation of the cervix.
- This progresses at around 1cm per hour, and there are strong and regular contractions.
Describe the second stage of labour [+]
The second stage of labour lasts from 10cm dilatation of the cervix to delivery of the baby.
The success of the second stage depends on “the three Ps”: power, passenger and passage.
1. Power:
- the strength of the uterine contractions.
2. Passenger: the four descriptive qualities of the fetus:
- Size: particularly the size of the head as this is the largest part.
- Attitude: the posture of the fetus. For example, how the back is rounded and how the head and limbs are flexed.
- Lie: the position of the fetus in relation to the mother’s body: Longitudinal lie – the fetus is straight up and down; Transverse lie – the fetus is straight side to side; Oblique lie– the fetus is at an angle.
- Presentation: the part of the fetus closest to the cervix: Cephalic (head first); Shoulder presentation (shoulder first); Breech presentation (legs first)
3. Passage: the size and shape of the passageway, mainly the pelvis.
What are the signs of labour? [4]
Abdominal pains – regular, initial frequency 2-3 in 10 minutes
Passage of show – mucous plug, brownish or blood stained (not always)
Water leak (often) – but typically waters should break in labour
Others (nausea, vomiting, general malaise…)
Describe the monitoring given in labour for the fetus [1] and mother [5]
Fetus:
* FHR monitored every 15min (or continuously via CTG)
Maternal:
* Maternal pulse rate assessed every 60min
* Maternal BP and temp should be checked every 4 hours
* VE should be offered every 4 hours to check progression of labour
* Maternal urine should be checked for ketones and protein every 4 hours
* Contractions assessed every 30min
Average labour duration:
[] hours for a primipara
[] hours for a multipara
Average labour duration:
8 hours for a primipara
5 hours for a multipara
A partogram is used to monitor the active phase of the first stage of labour.
Describe what you would measure on the partogram and what it would indicate if these were atypical [+]
A tool for monitoring maternal and foetal wellbeing during the active phase of labour, and a decision-making aid when abnormalities are detected
Fetal HR
- Normal is 110-160
Maternal pulse, BP, temperature
- raised if chorioamnionitis, UTI, group B streptococcal infection)
Maternal urianalysis
- protein = pre-eclampsia/liquor contamination; glucose = diabetes; ketones = starvation; blood = UTI/obstructed labour
Contractions:
- Frequency per 10 mins: 2nd stage of labour aim is 1min contractions in 10 mins, 3-5 strong)
- Strength
- Regularity
Cervical dilatation:
- PV exam performed every 4hrs: aim is 1cm/hr primiparous, 2cm/hr multiparous
- Alert line: 1cm/2hrs if primiparous or 1cm/hr if multiparous
Head descent:
- PV exam every 4 hrs
- Assess: Fifths palpable per abdomen; station of presenting part (measured in relation to ischial spine); position (orientation of fetal head - feel for fontanelles/sutures); moulding (extent of overlapping fetal skull bones); caput: swelling of presenting part
Liquor:
- Noted every hour
- Assess if intact: clear (membrane rupture), bloody (placental abruption) or meconium present (fetal distress)
Which medical devices would you use for HR in 1st or 2nd stage if there were no concerns? [2]
During 1st and 2nd stage how often would you check? [2]
What would you move to next if you were concerned? [1]
Intermittant ascultations: Pinard stethoscope or Doppler ultrasound
1st stage:
- Every 15 minutes, after a contraction, for 1 minute; record maternal pulse hourly
2nd stage: Every 5 minutes, after a contraction, for 1 minute; record maternal pulse every 15 min
Record accelerations and decelerations !!!
Move to CTG if any concerns
CTG:
- What is baseline tachycardia [1] and bradycardia [1]
- What are potential causes of fetal tachycardia? [4]
- What are potential causes of fetal bradycardia? [2]
Baseline bradycardia: HR < 100
- Increased fetal vagal tone
- Maternal beta blocker use
Baseline tachycardia: HR > 160:
- Maternal pyrexia
- chorioamnionitis
- fetal hypoxia
- fetal or maternal anaemia
- prematurity
- hyperthyroidism
Describe what is meant by an early deceleration in CTG? [1]
What are the causes of early deceleration in CTG? [1]
Deceleration of the heart rate which commences with the onset of a contraction and returns to normal on completion of the contraction
- They are caused by the uterus compressing the head the fetus, stimulating the vagus nerve of the fetus, slowing the heart rate
CTG:
- What is fetal bradycardia? [1]
- What are two common causes for fetal bradycardia? [2]
- Severe prolonged bradycardia count as less than [] bpm for more than 3mins. What are the causes? [4]
Fetal bradycardia is defined as a baseline heart rate of less than 110 bpm.
Fetal bradycardia is common in postdate gestation or OP or transverse presentations
Severe prolonged bradycardia (less than 80 bpm for more than 3 minutes) indicates severe hypoxia:
* Prolonged cord compression
* Cord prolapse
* Epidural and spinal anaesthesia
* Maternal seizures
* Rapid fetal descent
What can caused reduced variability in CTGs? [6]
Fetal sleeping: this should last no longer than 40 minutes (this is the most common cause)
Fetal acidosis (due to hypoxia): more likely if late decelerations are also present
Fetal tachycardia
Drugs: opiates, benzodiazepines, methyldopa and magnesium sulphate
Prematurity: variability is reduced at earlier gestation (< 28 weeks)
Congenital heart abnormalities
Describe the difference in causes between early, late and prolonged decelerations [3]
Early decelerations start when the uterine contraction begins and recover when uterine contraction stops
- This is due to increased fetal intracranial pressure causing increased vagal tone.
- It therefore quickly resolves once the uterine contraction ends and intracranial pressure reduces
- considered to be physiological and not pathological.
Late decelerations
- begin at the peak of the uterine contraction and recover after the contraction ends
- This type of deceleration indicates there is insufficient blood flow to the uterus and placenta. As a result, blood flow to the fetus is significantly reduced causing fetal hypoxia and acidosis.
Prolonged deceleration:
* A prolonged deceleration is defined as a deceleration that lasts more than 2 minutes:
* If it lasts between 2-3 minutes it is classed as non-reassuring.
If it lasts longer than 3 minutes it is immediately classed as abnormal.
The accelerations before and after a variable deceleration are known as the [] of deceleration. What do they indicate? [1]
The accelerations before and after a variable deceleration are known as the shoulders of deceleration
- Their presence indicates the fetus is not yet hypoxic and is adapting to the reduced blood flow.
- Variable decelerations without the shoulders are more worrying, as it suggests the fetus is becoming hypoxic.
What does a sinusoidal CTG patten indicate? [3]
A sinusoidal pattern usually indicates one or more of the following:
* Severe fetal hypoxia
* Severe fetal anaemia
* Fetal/maternal haemorrhage
Describe the different positions of the baby’s head during labour (and which ones are problematic) [4]
Occipito-anterior (OA):
- optimal position
- baby is head down with his or her face looking at spine
occipito-posterior (OP):
- baby is head down, facing naval
Occiput Transverse (OT) - R or L
- This is when the baby is lying at a right angle across the parent’s abdomen.
Breech
- Breech is when the baby is lying bottom down in the womb.
How can you determine which position the baby is during birth by feeling its head? [1]
Look at the fontanelles to determine position
- Posterior is triangular; hard;
- Anterior is a diamond; soft
- Therefore if the posterior further up: OA
Can feel the sagitalle suture (long one) - follow along until other suture. If theres 3 its posterior; if 4 and anterior is soft
Describe the pathophysiology of POI [2]
What will hormonal analysis show?
Premature ovarian insufficiency is characterised by hypergonadotropic hypogonadism.
Under-activity of the gonads (hypogonadism) means there is a lack of negative feedback on the pituitary gland, resulting in an excess of the gonadotropins (hypergonadotropism).
Hormonal analysis will show:
* Raised LH and FSH levels (gonadotropins)
* Low oestradiol levels
