Perineal tears and repairs

The data concerns perineal status in mothers after vaginal birth. The clinical indicator (3.1-3.6) additionally includes surgical repair of perineal tears and concerns only selected first time mothers.

These data come from the NSW Perinatal Data Collection (PDC) where they are coded according to a completed NSW Perinatal Data Collection Form (also called NSW Midwives Data Collection Form), which can be accessed via the intranet by NSW Health staff at http://internal.health.nsw.gov.au/data/collections/mdc/NSWH%20Perinatal%20Data.pdf.

Terminology used

Selected first time mother (primipara) is a woman 20-34 years of age at the time of giving birth, giving birth for the first time at greater than 20 weeks gestation; singleton pregnancy; cephalic presentation; and at 37 to 40 completed weeks gestation.

Perineum is the name for pelvic floor and associated structures occupying the pelvic outlet. It is bounded anteriorly by the pubic symphysis, laterally by ischial tuberosities and posteriorly by the coccyx.

Episiotomy is a surgical incision of the perineum and vagina to enlarge the vulvar orifice before or during birth. It is undertaken in cases of instrumental vaginal birth or when there is suspected fetal compromise. Episiotomy is not performed routinely in spontaneous vaginal birth. It is strongly associated with a higher frequency of third and fourth degree tears.

Perineal status after childbirth

Perineum can be intact or sustain one of the following:

1st degree tear: a perineal graze-laceration-tear involving: the fourchette, hymen, labia, skin, vaginal or vulva.

2nd degree tear: a perineal laceration or tear involving the pelvic floor or perineal muscles or vaginal muscles.

3rd degree tear: a perineal laceration-tear involving the anal sphincter or retrovaginal septum.

4th degree tear: a third degree perineal laceration or tear that also involves the anal mucosa or rectal mucosa.  

Management of perineal tears

Third and fourth degree tears are not necessarily obvious and all women having an operative vaginal delivery or who have experienced any perineal injury are examined by an experienced practitioner trained in the recognition and management of perineal tears.

Repair of third and fourth degree tears is usually conducted in an operating theatre, under regional or general anaesthesia.