Delivery

Question 1

Premature rupture of the membranes

PROM

Answer 1

the rupture of fetal membranes at least 1 hour prior to the onset of labour, at ≥37 weeks gestation.
It occurs in 10-15% of term pregnancies, and is associated with minimal risk to the mother and fetus due to the advanced gestation.

Question 2

Pre-term premature rupture of the membranes (P-PROM)

Answer 2

the rupture of fetal membranes occurring at <37 weeks gestation.
It complicates ~2% of pregnancies and has higher rates of maternal and fetal complications. It is associated with 40% of preterm deliveries.

Question 3

Pathophysiology of PROM

Answer 3

Early activation of normal physiological processes – higher than normal levels of apoptotic markers and MMPs in the amniotic fluid.

Infection – inflammatory markers e.g. cytokines contribute to the weakening of fetal membranes.

Genetic predisposition

Question 4

Prolonged rupture of membranes

Answer 4

amniotic sac ruptures more than 18 hours before delivery

Question 5

risk factors PROM/P-PROM

Answer 5

smoking
previous PROM-pre-term delivery
vaginal bleeding during pregnancy
lower genital tract infection
invasive procedures, e.g. amniocentesis
multiple pregnancy
cervical insufficiency

Question 6

Prematurity classification

Answer 6

Under 28 weeks: extreme preterm

28 – 32 weeks: very preterm

32 – 37 weeks: moderate to late preterm

Question 7

clinical features of PROM

Answer 7

painless popping sensation
gush of water
gradualleakage of watery fluid from the vagina
fluid draining from cervix and pooling in posterior vaginal fornix
washed cleann- lack of normalvaginal discharge

Question 8

options for prophylaxis of pre-term labour

Answer 8

vaginal progesterone

cervical cerclage

Question 9

vaginal; progesterone for prophylaxis of pre-term labour

Answer 9

Progesterone can be given vaginally via gel or pessary as prophylaxis for preterm labour. Progesterone has a role in maintaining pregnancy and preventing labour by decreasing activity of the myometrium and preventing the cervix remodelling in preparation for delivery. This is offered to women with a cervical length less than 25mm on vaginal ultrasound between 16 and 24 weeks gestation.

Question 10

cervical cerclage for prophylaxis of pre-term labvour

Answer 10

Cervical cerclage involves putting a stitch in the cervix to add support and keep it closed. This involves a spinal or general anaesthetic. The stitch is removed when the woman goes into labour or reaches term.

Cervical cerclage is offered to women with a cervical length less than 25mm on vaginal ultrasound between 16 and 24 weeks gestation, who have had a previous premature birth or cervical trauma (e.g. colposcopy and cone biopsy).

“Rescue” cervical cerclage may also be offered between 16 and 27 + 6 weeks when there is cervical dilatation without rupture of membranes, to prevent progression and premature delivery.

Question 11

PROM differentials

Answer 11

urinary incontinence
normal vaginal secretions of pregnancy
increased sweat/moisture arounbd perineum
increased cervical discharge
vesicovaginal fistula
loss of mucus plug

Question 12

investigations for PROM

Answer 12

high vaginal swab for GBS, figure out cause (BV)
ferning test
actim-PROM
amnisure
nitrazine testing

Question 13

ferning test

Answer 13

placing cervical secretion onto a glass slide and allowing it to dry (forming fern-patterned crystals if there is PROM/PPROM). The false positive rate is around 6%.

Question 14

Actim-PROM (Medix Biochemica)

Answer 14

uses a swab test looking for IGFBP-1 (insulin-like growth factor binding protein-1) in vaginal samples. The concentration in amniotic fluid is 100 – 1000 times the concentration of maternal serum. This test is unlikely to be affected by blood contamination

Question 15

Amnisure (QiaGen) –

Answer 15

looks for Placental alpha microglobulin-1 (PAMG-1) which is present in the blood, amniotic fluid (in large concentrations) and cervico-vaginal discharge of pregnant women (in low concentrations with membranes intact).

Question 16

Nitrazine testing

Answer 16

measures the pH of vaginal fluids and has previously been used to diagnose PROM and PPROM (amniotic fluid pH is higher than vaginal fluids). However, this test carried a high false positive rate (17%), due to contamination with urine, blood or semen – and is no longer routinely used.

Question 17

PROM management >36 weeks

Answer 17

Monitor for signs of clinical chorioamnionitis.
Clindamycin/penicillin during labour if GBS isolated.

Watch and wait for 24 hours (60% of women go into labour naturally), or consider induction of labour.

IOL and delivery recommended if greater than 24 hours (but women can wait up to 96 hours – beyond this is their choice after counselling)

Question 18

PROM management 34-36 weeks

Answer 18

Monitor for signs of clinical chorioamnionitis, and advise patient to avoid sexual intercourse (can increase risk of ascending infection).
Prophylactic erythromycin 250 mg QDS for 10 days.

Clindamycin/penicillin during labour if GBS isolated.

Corticosteroids if between 34 and 34+6 weeks gestation.

IOL and delivery recommended.

Question 19

24-33 weeks PROM management

Answer 19

Monitor for signs of clinical chorioamnionitis, and advise patient to avoid sexual intercourse.
Prophylactic Erythromycin 250 mg QDS for 10 days.

Corticosteroids (as less than 34+6).

Aim expectant management until 34 weeks.

Question 20

diagnossi Pre-term labour with intact membrANES

Answer 20

Clinical assessment includes a speculum examination to assess for cervical dilatation. The NICE guidelines (2017) recommend:

Less than 30 weeks gestation, clinical assessment alone is enough to offer management of preterm labour.

More than 30 weeks gestation, a transvaginal ultrasound can be used to assess the cervical length. When the cervical length on ultrasound is less than 15mm, management of preterm labour can be offered. A cervical length of more than 15mm indicates preterm labour is unlikely.

fetal fibronectin

Question 21

fetal fibronectin in diagnosis pre-term labour with intact,membranes

Answer 21

Fetal fibronectin is an alternative test to vaginal ultrasound. Fetal fibronectin is the “glue” between the chorion and the uterus, and is found in the vagina during labour. A result of less than 50 ng/ml is considered negative, and indicates that preterm labour is unlikely.

Question 22

pre-term labour with intact membranes

Answer 22

regular painful contractions

cervical dilatation without rupture of amniotic sac

Question 23

management of pre-term labour

Answer 23

Fetal monitoring (CTG or intermittent auscultation)

Tocolysis with nifedipine: nifedipine is a calcium channel blocker that suppresses labour

Maternal corticosteroids: can be offered before 35 weeks gestation to reduce neonatal morbidity and mortality

IV magnesium sulphate: can be given before 34 weeks gestation and helps protect the baby’s brain

Delayed cord clamping or cord milking: can increase the circulating blood volume and haemoglobin in the baby at birth

Question 24

Tocolysis

Answer 24

Tocolysis involves using medications to stop uterine contractions.

Nifedipine, a calcium channel blocker, is the medication of choice for tocolysis.

Atosiban is an oxytocin receptor antagonist that can be used as an alternative when nifedipine is contraindicated.

Tocolysis can be used between 24 and 33 + 6 weeks gestation in preterm labour to delay delivery and buy time for further fetal development, administration of maternal steroids or transfer to a more specialist unit (e.g. with a neonatal ICU). It is only used as a short term measure (i.e. less than 48 hours).

Question 25

complications of PROM

Answer 25

``` chorioamnionitis oligohydramnios neonatal death placental abruption umbilical cord prolapse ```

Question 26

instrument types for assisted vaginal delivery

Answer 26

ventouse | forceps

Question 27

maternal indications for assisted vaginal delivery in multiparous women

Answer 27

expect delivery with one hour of active pushing, with an hour for descent if needed prior to active pushing.

Question 28

maternal indications for assisted vaginal delivery in nulliparous women

Answer 28

as a general rule, expect delivery after two hours of active pushing. If no urge to push is felt at the diagnosis of second stage (common with regional anaesthesia), an hour can be allowed for fetal descent before starting active pushing.

Question 29

maternal indication for performing an assisted vaginal delivery

Answer 29

inadequate progress maternal exhaustion intracranial pathologies, maternal congenital heart diseases and severe HTN

Question 30

fetal indications for performing an assisted vaginal delivery

Answer 30

fetal compromise CTG abnormal fetal blood sample significant antepartum haemorrhage

Question 31

absolute contraindications to instrumental delivery

Answer 31

Unengaged fetal head in singleton pregnancies. Incompletely dilated cervix in singleton pregnancies. True cephalo-pelvic disproportion (where the fetal head is too large to pass through the maternal pelvis). Breech and face presentations, and most brow presentations. Preterm gestation (<34 weeks) for ventouse. High likelihood of any fetal coagulation disorder for ventouse.

Question 32

relative contraindications to instrumental delivery

Answer 32

Severe non-reassuring fetal status (‘acute fetal distress’), with station of the head above the level of the pelvic floor – i.e. fetal scalp not visible. Delivery of the second twin when the head has not quite engaged, or the cervix has reformed. Prolapse of the umbilical cord with fetal compromise when the cervix is completely dilated and the station is mid cavity.

Question 33

pre-requisites for instrumental delivery

Answer 33

``` fully dilated ruptured membranes cephalic presentation defined fetal position fetal head at least at the level of the ischial spines empty bladder adequate pain relief adequate maternal pelvis ```

Question 34

fetal complications of instrumental delivery

Answer 34

Neonatal jaundice Scalp lacerations Cephalohaematoma Subgaleal haematoma Facial bruising Facial nerve damage Skull fractures Retinal haemorrhage

Question 35

maternal complications of instrumental delivery

Answer 35

VTE Incontinence PPH Shoulder dystocia Infection vaginal tears

Question 36

Indications for induction of labour

Answer 36

``` prolonged gestation premature rupture of membranes maternal health problems: existing diabetes, pre-eclampsia, obstetric cholestasis fetal growth restriction intrauterine fetal death ```

Question 37

bishops score

Answer 37

Fetal station (scored 0 – 3) Cervical position (scored 0 – 2) Cervical dilatation (scored 0 – 3) Cervical effacement (scored 0 – 3) Cervical consistency (scored 0 – 2)

Question 38

absolute contraindications for induction of labour

Answer 38

Cephalopelvic disproportion Major placenta praevia Vasa praevia Cord prolapse Transverse lie Active primary genital herpes Previous classical Caesarean section

Question 39

relative contraindications for induction of labour

Answer 39

Breech presentation Triplet or higher order pregnancy Two or more previous low transverse caesarean sections

Question 40

options for induction of labour

Answer 40

vaginal prostaglandins amniotomy membrane sweep

Question 41

membrane sweep in induction of labour

Answer 41

Membrane sweep involves inserting a finger into the cervix to stimulate the cervix and begin the process of labour. It can be performed in antenatal clinic, and if successful, should produce the onset of labour within 48 hours. A membrane sweep is not considered a full method of inducing labour, and is more of an assistance before full induction of labour. It is used from 40 weeks gestation to attempt to initiate labour in women over their EDD.

Question 42

vaginal prostaglandins E2 in induction of labour

Answer 42

involves inserting a gel, tablet (Prostin) or pessary (Propess) into the vagina. The pessary is similar to a tampon, and slowly releases local prostaglandins over 24 hours. This stimulates the cervix and uterus to cause the onset of labour. This is usually done in the hospital setting so that the woman can be monitored before being allowed home to await the full onset of labour.

Question 43

cervical ripening balloon in induction of labour

Answer 43

silicone balloon that is inserted into the cervix and gently inflated to dilate the cervix. This is used as an alternative where vaginal prostaglandins are not preferred, usually in women with a previous caesarean section, where vaginal prostaglandins have failed or multiparous women (para ≥ 3).

Question 44

artificial rupture of membrane in induction of labour

Answer 44

Artificial rupture of membranes with an oxytocin infusion can also be used to induce labour, although this would only be used where there are reasons not to use vaginal prostaglandins. It can be used to progress the induction of labour after vaginal prostaglandins have been used. Oral mifepristone (anti-progesterone) plus misoprostol are used to induce labour where intrauterine fetal death has occurred.

Question 45

monitoring in induction of labour

Answer 45

Cardiotocography (CTG) to assess the fetal heart rate and uterine contractions before and during induction of labour Bishop score before and during induction of labour to monitor the progress

Question 46

uterine hyperstimulation in induction of labour

Answer 46

Uterine hyperstimulation is the main complication of induction of labour with vaginal prostaglandins. This is where the contraction of the uterus is prolonged and frequent, causing fetal distress and compromise.

Question 47

complications of uterine hyperstimulation

Answer 47

Fetal compromise, with hypoxia and acidosis Emergency caesarean section Uterine rupture

Question 48

first line induction of labour

Answer 48

vaginal prostaglandins

Question 49

bishop score >=7

Answer 49

suggests cervix is ripe or favourable | high change of a response to interventions made to induce labour

Question 50

bishop score <4

Answer 50

labour unlikely to progress naturally and prostaglandin will be required

Question 51

complications of induction of labour

Answer 51

``` failure of induction uterine hyperstimulation cord prolapse infection pain increased rate of further intervention vs spontaneous labvour uterine rupture ```

Question 52

categories of c section

Answer 52

Category Description 1 Immediate threat to the life of the woman or fetus 2 Maternal or fetal compromise that is not immediately life-threatening 3 No maternal or fetal compromise but needs early delivery 4 Elective – delivery timed to suit woman or staff

Question 53

indications for planned or elective c section

Answer 53

``` breech other malpresentations twin pregnancy fetal compromise maternal medical conditions transmissable disease primary genital herpes placenta praevia maternal diabetes with big baby previous major shoulder dystocia maternal request previous 3rd degree tear ```

Question 54

pre-op for c-section

Answer 54

FBC and G&S H2 receptor antagonist, reduces Mendelson's syndrome VTE

Question 55

Layers from skin incision to uterus for C-section

Answer 55

``` skin camper's fascia scarpa's fascia rectus sheath rectus muscle abdominal peritoneum uterus ```

Question 56

immediate complications of c section

Answer 56

Postpartum haemorrhage (>1000ml) ``` Wound haematoma (increased in patient with large BMI/diabetes/immunosuppressed) ``` Intra-abdominal haemorrhage Bladder/bowel trauma (more common in patients who have had previous abdominal surgery) Neonatal: transient tachypnoea of the newborn fetal lacerations (1-2% risk, higher with previous membrane rupture)

Question 57

intermediate complications of c section

Answer 57

Infection: urinary tract infection endometritis respiratory (higher risk if general anaesthetic used) Venous thromboembolism

Question 58

late complications of c section

Answer 58

Urinary tract trauma (fistula) Subfertility (there is a delay in conceiving compared to women who have had vaginal deliveries) Regret and other negative psychological sequelae Rupture/dehiscence of scar at next labour (VBAC) Placenta praevia/accreta Caesarean scar ectopic pregnancy