Complicated Pregnancy

Question 1

What is the definition of prematurity?

Answer 1

Prematurity is defined as birth before 37 weeks gestation. The more premature the baby, the worse the outcomes.

Question 2

What is the survival rate of babies born at 23 weeks?

Answer 2

10% chance of survival

Question 3

Below how many weeks gestation are babies considered to be “non-viable”?

Answer 3

below 23 weeks gestation

Question 4

What is the survival rate of babies born at 23 weeks?

Answer 4

10% chance of survival

Question 5

From how many weeks is resuscitation offered for premature babies?

Answer 5

From 24 weeks onwards

Question 6

Prematurity

How many weeks gestation is classified by the WHO as extreme preterm?

Answer 6

Under 28 weeks

Question 7

Prematurity

How many weeks gestation is classified by the WHO as very preterm?

Answer 7

28-32 weeks

Question 8

Prematurity

How many weeks gestation is classified by the WHO as moderate to late preterm?

Answer 8

32-37 weeks

Question 9

What are prophylaxis methods of preterm labour?

Answer 9

• Vaginal Progesterone
• Cervical Cerclage

Question 10

How does vaginal progesterone act as a prophylaxis for preterm labour?

Answer 10

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.

Question 11

How is vaginal progesterone given for prophylaxis of preterm labour?

Answer 11

Progesterone can be given vaginally via gel or pessary as prophylaxis for preterm labour.

Question 12

To which women is vaginal progesterone offered as a prophylaxis of preterm labour?

Answer 12

It is offered to women with a **cervical length less than 25mm **on vaginal ultrasound between 16 and 24 weeks gestation.

Question 13

What is cervical cerclage?

Answer 13

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.

Question 14

To whom is cervical cerclage offered to as a prophylaxis for preterm delivery?

Answer 14

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).

Question 15

When is “Rescue” cervical cerclage offered?

Answer 15

“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 16

Definition

Preterm prelabour rupture of membranes (P‑PROM):

Answer 16

The amniotic sac has ruptured, releasing amniotic fluid, before the onset of labour and before 37 weeks gestation (preterm).

Question 17

How is P-PROM diagnosed?

Answer 17

By speculum examination revealing pooling of amniotic fluid in the vagina.

No further tests are required unless there is doubt about the diagnosis.

Question 18

Where there us doubt about a diagnosis of P-PROM, what tests can be performed?

Answer 18

• Insulin-like growth factor-binding protein-1 (IGFBP-1) is a protein present in high concentrations in amniotic fluid, which can be tested on vaginal fluid if there is doubt about rupture of membranes
• Placental alpha-microglobin-1 (PAMG-1) is a similar alternative to IGFBP-1

Question 19

Management of P-PROM

Answer 19

• Prophylactic antibiotics should be given to prevent the development of ** chorioamnionitis**. The NICE guidelines (2019) recommend erythromycin 250mg four times daily for ten days, or until labour is established if within ten days.
• Induction of labour may be offered from 34 weeks to initiate the onset of labour.

Question 20

What is Preterm Labour with Intact Membranes?

Answer 20

Preterm labour with intact membranes involves regular painful contraction and cervical dilatation, without rupture of the amniotic sac.

Question 21

How is Preterm Labour with Intact Membranes diagnosed?

Answer 21

Clinical assessment includes a speculum examination to assess for cervical dilatation.

NICE Guidlines 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.

Question 22

Premature Labour with Intact Membranes

What is Fetal Fibronectin?

Answer 22

Fetal fibronectin is an alternative test to vaginal ultrasound (in diagnosing premature labour with intact membranes). 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 23

Management options for preterm labour with intact membranes to improve outcomes:

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

What is the action of nifedipine in preterm labour?

Answer 24

nifedipine is a calcium channel blocker that suppresses labour

Question 25

What is the role of maternal corticosteroids in preterm labour?

Answer 25

Used to aid a rapid maturity of fetal lungs by enhancing the production of surfactant, thus enabling rapid expansion of the alveoli at the time of delivery to help prevent respiratory distress.

Question 26

What is the role of IV magnesium sulfate in preterm labour?

Answer 26

This is used to protect the baby’s brain (by reducing the incidence of little haemorrhages etc). It reduces the risk and severity of cerebral palsy.

Question 27

What is the role of delayed cord clamping or cord milking in preterm births?

Answer 27

Can increase circulating blood volume and haemoglobin

Question 28

What is Tocolysis?

Answer 28

A method of suppressing preterm labour using medications to stop uterine contractions. Nifedipine, a calcium channel blocker is the medication of choice. It is used 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 29

What is chorioamnionitis?

Answer 29

an acute inflammation of the membranes and chorion of the placenta, typically due to ascending bacteria due to a ruptured membrane.

Question 30

Example regime of corticosteroid dose to aid fetal lung maturity in premature labour?

Answer 30

3 doses of IM Betamethasone, 24 hours apart

Question 31

What are the signs of magnesium toxicity in a mother who has been given IV Magnesium sulfate?

Answer 31

• Reduced respiratory rate
• Reduced blood pressure
• Absent reflexes (usually test patella reflex)