Late pregnancy & Labour

Question 1

Stimulation of Labour

Answer 1

Labour brought on by non-spontaneous means after spontaneous rupture of membranes

Question 2

Induction of Labour

Answer 2

Artificially bringing on labour using chemical or physical means with membranes usually intact

Question 3

Augmentation of labour

Answer 3

stimulation of contractions after arrested progress in labour, once active labour has been diagnosed (>4cm)

Question 4

Normal Labour

Answer 4

‘Labour is normal when it is spontaneous in onset, low risk throughout the labour. Baby is born spontaneously in the vertex position between 37-42wks. After birth women and baby are in good condition’ WHO and NICE

Question 5

Modified Bishop’s score

Answer 5

Cervical dilation - 4cm
Consistency - firm - med - soft -
Length - >3cm - >2cm - >1cm - <1cm
Position - post - mid - anterior -
Station - -3 - -2 - -1/0 - +1/+2
Score - 1 - 2 - 3 - 4

Question 6

Induction of Labour (if bishops score 3 or less)

Answer 6

–> PGE2 1mg up to max 4mg PV in 24hrs
If SROM - PGE2 or oxytocin infusion 10u in 49mls
Can also use misoprostol (PGE1) but beware uterine rupture(25mcg 6hrly PV or 50mcg 4hrly PO)

Question 7

Cervical ripening using mechanical means

Answer 7

Foley cath balloons have no significant evidence base

Question 8

Induction of Labour (if bishops score >4)

Answer 8

1mg prostin
propress - long acting 10mg prostaglandin pessary left for 24hrs
Consider ARM

Question 9

Tocolytics

Answer 9

Used to prevent preterm labour -rarely used at term
B2 agonists (salbutamol/terbutaline) if hyperstimulated - 250mcg SC
Can also use atosiban
Nifedipine should not be used to treat HTN at term due to tocolytic activity

Question 10

First stage of labour (latent)

Answer 10

dilation of the cervix up to 4cm -interrupted and irregular contractions
should be up to 12hrs for primips and 6hrs for multips –> prolonged latent phase usually only diagnosed after 48hrs

Question 11

Risks of prolonged latent phase (>8hrs)

Answer 11

much more common in primips

Increased risk of LSCS, MEC staining, oxytocin augmentation, NICU admission, reduced Apgars at 5mins

Question 12

Active 1st stage

Answer 12

Regular, painful contractions with progressive dilation of the cervix - 4cm onwards - expect 0.5cm progress each hour

Question 13

Partogram

Answer 13

a graphical representation of cervical dilation over time

useful for detecting 2nd stage arrest

Question 14

Management of delay in the 1st stage of labour

Answer 14

ARM if membranes intact - 2hrly exams
consider augmentation if no progress (oxytocin infusion)
Consider passenger, passages and power (usually the problem in primips)

Question 15

Record of VE

Answer 15

First do abdominal exam for presentation, fifths palpable, uterine tone, CTG
VE: normal vulva and vagina,clear liqour draining, cervix 6cm dilated, fully effacted, station (relative to iliac spines), is there any caput/moudling etc

Question 16

Fetal moulding

Answer 16

The scalp bones are able to override each other during the descent through the pelvis

Question 17

Caput

Answer 17

Coning of the babies head. also known as caput sucadeneum

Question 18

Second stage of Labour

Answer 18

Full dilation till birth.
Also has a passive phase where additional descent may occur and an active phase where maternal effort is required for pushing
Should last 3hrs with active pushing in primips, 2hrs for multips

Question 19

3rd stage of labour

Answer 19

from delivery of the baby till delivery of the placenta
Can be active or physiological - active preferred as it reduces the risk of PPH
CCT with uterine guarding (risk of uterine inversion)

Question 20

Perineal trauma

Answer 20

Episiotomies are used to prevent tearing

Midline in US and mediolateral in UK (lower risk of 3rd/4th degree tears)

Question 21

Repair of perineal tears

Answer 21

vicryl rapide sutures with local infiltration of LA or pudendal block
Epidural is required for the repair of 3rd or 4th degree tears

Question 22

Classification of perineal tears

Answer 22

1st - superifical tears to the posterior labial frenulum, vaginal skin and mucosa
2nd - tear extends into the perineal muscles and fascia
3rd - a tear involving the anal sphincter
4th - a tear involving the anal sphincter and rectal mucosa

Question 23

Subclassification of 3rd degree perineal tears

Answer 23

3a - 50% of the external anal sphincter

3c - Internal sphincter is torn

Question 24

Cord Prolapse

Answer 24

An acute obstetric emergency. Exposure of the cord can cause irritation and cooling leading to vasospasm. ARM, transverse lie and Footling breech are all risk factors. (all malpresentations or unstable lies)

Question 25

Varieties of Cord Prolapse

Answer 25

Overt –> The cord slips past the presenting part into the cervix or vagina
Occult –> Where the cord lies alongside the presenting part. 50% of CTGs show some evidence of cord compression but it is usually transient and relieved by changing maternal position.
Funic –> felt to prolapse below the presenting part before the ROM and it may move or disappear as the membranes rupture.

Question 26

Management of Cord Prolapse

Answer 26

Overt –> place mother in head down, bum up and apply upward pressure to the presenting part manually or by filling the bladder. Do not handle the cord and proceed to emergency CS or expedited VD if well progressed.
Occult –> place mother in LL position and give Oxygen and montior continue if possible or Emergency CS
Funic –> Emergency CS or ARM with prep to convert.

Question 27

Classical CS

Answer 27

An Upper segement CS with a 1/25 risk of uterine rupture – do not attempt VBAC.

Question 28

Forceps used in delivery

Answer 28

Outlet (Wrigley’s) –> small and used for CS or when the head is visible and no more than 45 degrees of rotation is needed
Mid-cavity (Neville Barnes) –> where the head is 1/5 palpable or above station +2 and no more than 45 degrees of rotation
Rotational (Keilands) –> only used by experienced staff in theatre. Used to rotate the head, hold it in place and to reduce the risk of cord prolapse after manual disimpaction of the head.

Question 29

Management of pain after a CS

Answer 29

Paracetamol is first line in pregnancy for pain. Diclofenac is good but cannot be used in pregnancy or if breast-feeding.
Codeine shouldnt be used if breast feeding as it can cause respiratory depression.

Question 30

Syntometrine/oxytocin challenge test

Answer 30

Oxytocin transiently reduces placental blood flow by inducing a contraction and if this causes a late decleration it indicates fetal hypoxia due to low placental circulatory reserve. This may warrant immediate CS delivery