Pelvic floor

The sling of muscles that forms the soft tissue base to the bony pelvis. These muscles are stretched by childbirth and need to be exercised regularly both during and after pregnancy to improve their tone. See pelvic floor exercises.

Perineal block

A local anaesthetic given before an episiotomy is carried out.

Perineum

The triangular area of skin and underlying muscles between the vagina and the anus.

Pessary

A plug containing medication inserted into the vagina. In labour prostaglandin pessaries are used to induce labour.

Pethidine

A form of pain relief given by injection into the thigh or bottom. Pethidine usually makes women in labour sleepy and very relaxed. It can make the baby slow to breathe when he is born, in which case he may need an antidote.

Pica

A craving for specific and often unusual foods or food combinations during pregnancy. Some experts think that these cravings may indicates that the mother isn’t eating a healthy, balanced diet.

Placenta

The organ that develops in the uterus during pregnancy to transfer nourishment and oxygen to the baby from the mother’s system, and to take away the baby’s waste matter.

Placenta praevia

The placenta lies partly or completely over the cervix, instead of on the upper wall of the uterus. If the placenta remains in this position the baby will need to be born by Caesarean section. A placenta that partly covers the cervix in early pregnancy usually moves up and away as the uterus grows.

Postnatal depression

A form of depression which some women suffer from in the weeks or months after the baby is born. See Postnatal depression.

Postpartum

After the birth.

Presenting part (presentation)

The part of the baby coming first through the birth canal.

Primagravida

A woman having her first baby.

Prolapsed cord

Usually the baby’s cord is born along with the baby and it continues to supply oxygen to the baby until it is clamped and cut. Occasionally the cord slips down in front of the baby and the oxygen supply to the baby is reduced or cut off. This can happen with a breech baby or with a transverse or unstable lie. This is a medical emergency and the baby has be delivered very quickly, usually by an emergency Caesarean section.

Prostaglandin

A natural substance used in pessaries to soften the cervix and stimulate the start of labour.

Pudendal block

A local anaesthetic given to block pain around the cervix and vagina before using forceps.

Puerperal psychosis

A rare and extreme form of postnatal depression in which the woman hears voices and suffers delusions.