Labour and Childbirth
by Dr. Derrick Thompson (Obstetrician and Gynaecologist)
How to know when your labour has started
As your Estimated delivery date (EDD) approaches, some of the most frequently asked questions are:
- How do I know if I am in labour?
- When should I ring the birthing suite and go to hospital?
There are four factors to assess which should tell you whether you are in labour:
- the onset of regular painful contractions (plus one or more of the following signs).
- a bright show of blood like the start of a period.
- whether your membranes have ruptured, that is, your waters have broken.
- whether your cervix is dilated.
Whether you are being cared for by a doctor or a midwife, the first decision to be made when you are admitted to the birthing suite is whether you are in established labour. In my experience, a definite diagnosis of established labour is of the utmost importance in the management of your labour. Most prolonged labours happen because a definite diagnosis of established labour was made at the outset.
Most of the time you, as the mother, will make the initial diagnosis. When you ring the birthing suite and if the on-duty midwife established labour has started, you will be advised to come into hospital. On admission to the birthing suite, it is the duty of the midwife or doctor to confirm the diagnosis of established labour. Once this has been determined, you should give birth within 12 hours!
Regular painful contractions
When you notice the onset of regular, 5-10 minutely painful contractions (muscular tightening of the uterine muscle), you can assume you are starting labour. You may have irregular painful contractions for a day or two before they become regular.
A blood-stained show by itself does not mean you are in labour or are going into labour. However, when this is combined with regular painful contractions, it usually means you are in labour.
A blood show often occurs a number of days before the onset of labour, but it does not automatically mean you are going to come into labour. It probably happens because the cervix is ripening prior to labour beginning. ripening means that the tissues of the cervix are becoming softer and the canal of the cervix is becoming shorter. This is known as effacement.
With a first pregnancy, effacement usually happens before the cervix starts to dilate, but if you have had a baby before, effacement and dilatation tend to occur at the same time.
You may be aware of a sudden mucous vaginal discharge. Be careful not to confuse a mucous show with a blood show. The mucous plug can be dislodged form the cervix at any time before the onset of labour, although it is more commonly dislodged during the last few weeks of your pregnancy. It is not a sign of imminent labour.
The breaking of your waters (known also as liquor) is not a sign of labour.
It can be sometimes difficult to tell whether your membranes have ruptured. You may have suffered from some urinary incontinence when straining or changing position. When pregnant, you are usually aware of an increased vaginal discharge which makes you feel wet, especially if you change position or strain. If you suspect that your membranes have ruptured, lie down flat and put on a sanitary pad. If the pad gets soaked through while you are resting flat or in a reclined position, it is highly likely that your waters have broken, and you should ring the birthing suite of the hospital.
Once you are admitted into the birthing suite, your doctor may perform a vaginal examination with a sterile speculum to check your cervix. If your waters have broken, the vagina has a glistening appearance, and liquor can be seen draining thought the cervix or pooling in the upper vagina. A vaginal swab may be taken to test for infection, which could be associated with your membranes rupturing.
If you are due – that is, your pregnancy is at term – one option is to wait and see if you come into spontaneous labour during the next 24 hours. It has been shown that 85% of pregnant women will come into natural labour within 24 hours of premature rupturing of membranes. If you are more than 36 weeks pregnant with ruptured membranes, most carers will recommend inducing labour after this gestation, using intravenous suntocinon, a chemical which stimulates the uterine muscle to contract.
Vaginal prostaglandin in gel or tablet form is sometimes used to induce labour. You will be started on antibiotics if your membranes have been ruptured for more than 18 hours, or if you are GBS positive. Induction of labour within 24 hours reduces the risks of you developing an infection of the genital tract and the risks of GBS infection of your baby if you have not been screened for this genital tract bacterium.
Indications for “induction of labour”
The most common reason to be induced is prolonged pregnancy (post-maturity), that is, more than 2 weeks overdue, although 10 days overdue is often taken as a guideline for induction. If you are not going to be induced at about 41 weeks gestation, your baby will need to be closely monitored. After 41 weeks, it is recommended that you should have fetal monitoring every second day, consisting of a CTG and an ultrasound scan to assess the amount of fluid around your baby.
The likelihood of a prolonged labour, fetal distress indicated by meconium stained liquor and instrumental birth are problems associated with post-maturity. The risks of perinatal morbidity and mortality are also increased in the post-term pregnancy. Please note that if your are induced, it doesn’t increase the need for birthing by c-section if your cervix is favorable. It is also worth noting that you are less likely to be induced for post-maturity if your baby’s head is engaged prior to your due date.
Other signs which can indicate that you may need to be induced are:
- poor fetal growth due to placental insufficiency (small-for-dates fetus) or IUGR (intrauterine growth retardation)
- rhesus isoimmunisation causing the fetus to become anemic
- fetal malformation
For maternal reasons
- an antepartum haemorhhage due to abruption (separation) of the placenta from the wall of the uterus
- pre-labour rupture of membranes
- impaired liver function, for example hepatitis C or cholestasis of pregnancy