Labour is 'premature' if it occurs after 24 weeks gestation and before 37 weeks gestation. If it is before 24 weeks of gestation it is termed a miscarriage.
Incidence: 6% of labours
- BMI <19
- Low social class
- Extremes of reproductive age <20 or >35
- Domestic violence
- Previous pre-term labour
- Bacterial vaginosis
- Chronic medical conditions
Clinical evaluation and examination
- Labour is often rapid and unexpected
- Check the mother is stable
- If presentation is less acute take a history and perform an examination; this may help to find the cause of threatened labour
- Speculum examination for inspection of the cervix and take high vaginal and endocervical swabs.
- If there is cervical dilatation start CTG
- Abnormal lie is common so ultrasound scan should be performed.
- Give corticosteroids (to help fetal lung maturation)
- Contact the paediatricians
- Discuss the mode of delivery
- The patient will require some pain relief
- Given prophylactically if membranes have ruptured before term to protect the fetus from infection
These may be used to delay labour for up to 48 hours. It is not sensible to use tocolytics when:
- The membranes have ruptured
- Maternal illness that would be helped by delivery e.g. pre-eclampsia
- The fetus is distressed
- If there has been substantial vaginal bleeding
If the patient is not in labour but there is cervical incompetence a suture can be placed in the cervix to try to reduce the prolapse of membranes that will otherwise occur.