Perineal tears

Question 1

How does a perineal tear usually occur?

Answer 1

Where the external vaginal opening is too narrow to accommodate the baby. This leads to the skin and tissues in that area tearing as the baby’s head passes.

Question 2

In what cases are perineal tears most common?

Answer 2

• First births (nulliparity)
• Large babies (over 4kg) = macrosomia
• Shoulder dystocia
• Asian ethnicity
• Occipito-posterior position
• Instrumental deliveries

Question 3

How many degrees of perineal tears are there?

Answer 3

4 degrees (grade 1 - grade 4)

Question 4

Grade 1 perineal tear?

Answer 4

Injury to perineal skin, frenulum of labia minora.

Question 5

Grade 2 perineal tear?

Answer 5

Injury to perineum involving perineal muscles. No involvement of anal sphincters.

Question 6

Grade 3 perineal tear and the subtypes?

Answer 6

Injury to perineum involving anal sphincter complex:
3a: <50% of external anal sphincter thickness
3b: >50% of external anal sphincter thickness
3c: both external and internal anal sphincter

Question 7

Grade 4 perineal tear?

Answer 7

Injuries to all areas including rectal mucosa

Question 8

Do first degree perineal tears require treatment?

Answer 8

First-degree tears usually do not require any sutures. When a perineal tear larger than first degree occurs, the mother usually requires sutures to correct the injury.

A third or fourth-degree tear is likely to need repairing in theatre.

Question 9

For perineal tear management, what additional measures are taken to reduce risk of complications?

Answer 9

Broad-spectrum antibiotics to reduce the risk of infection

Laxatives to reduce the risk of constipation and wound dehiscence

Physiotherapy to reduce the risk and severity of incontinence

Follow-up to monitor for longstanding complications

Question 10

What are women who are symptomatic after 3rd or 4th degree tears offered?

Answer 10

offered an elective caesarean section in subsequent pregnancies

Question 11

Short term complications from perineal tear after repair?

Answer 11

Pain
Infection
Bleeding
Wound dehiscence or wound breakdown

Question 12

Perineal tears can lead to several lasting complications. What are these complications?

Answer 12

• Urinary incontinence
• Anal incontinence and altered bowel habit (third and fourth-degree tears)
• Fistula between the vagina and bowel (rare)
• Sexual dysfunction and dyspareunia (painful sex)
• Psychological and mental health consequences

Question 13

What is an episiotomy?

Answer 13

Where the obstetrician or midwife cuts the perineum before the baby is delivered. This is done in anticipation of needing additional room for delivery of the baby (e.g. before forceps delivery). It is performed under local anaesthetic.

Cut is made at around 45 degrees diagonally, from the opening of the vagina downwards and laterally, to avoid damaging the anal sphincter. This is called a mediolateral episiotomy. The cut is sutured after delivery.

Question 14

What is a perineal massage?

Answer 14

A method for reducing the risk of perineal tears. It involves massaging the skin and tissues between the vagina and anus (perineum).

This is done in a structured way from 34 weeks onwards to stretch and prepare the tissues for delivery.