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Pre-natal Tests


Foetal Presentation

In the third trimester you will see your midwife/ doctor fortnightly, then weekly from around week 36. At this stage, in addition to routine checks, she will be assessing your baby’s position right up until labour. If the baby is transverse lie (with his spine at a right angle to the mother’s), then a vaginal birth may be impossible. If he is breech (accounting for around four percent of all births), this can also cause problems, as it may be difficult to deliver the head after the legs and bottom have emerged. Some hospitals are happy to still attempt a vaginal delivery; others prefer to deliver by caesarean.

If the baby is breech after 36 weeks your midwife/ doctor may try to turn him manually – a technique known as external cephalic version (ECV). This is carried out in conjunction with an ultrasound scan and the foetal heartbeat is monitored before and after turning. The success rate for ECV is 70 per cent, although some babies turn back again.

Another method of helping turn a breech baby is moxibustion, in which a cigar-shaped stick containing the herb mugwort is placed, smouldering, at an acupuncture point at the outer corner of the little toe. It may sound esoteric, but it has a pre-sorted success rate of about 60 per cent if carried out at 34 – 38 weeks. For a more conventional approach, you can adopt positions that will encourage your baby to turn: kneel with your head down and bottom in the air, or lie across a bean bag in the knee-to-chest position for 15 minutes, three times a day.

Placental Function

If you pass your EDD (estimated delivery date), you are overdue. This is normal; seven out of ten babies arrive after their due date. However, if you go several days beyond your EDD, there may be concern that the placenta is not providing enough nourishment to the baby. The risk of stillbirth, which occurs in one per cent of pregnancies, doubles by 43 weeks and trebles by week 44.

To test placental function you will be given an ultrasound scan to gauge the flow of blood through the umbilical blood vessels and to measure amniotic fluid. Electronic foetal monitoring will check whether the baby’s heart rate levels are normal during rest and active periods. If all is well you will be able to wait for labour to begin spontaneously, instead of being induced.

If overdue, be aware of your baby’s usual pattern of movements. If you do not feel him move over a six hour period, alert you midwife/ doctor.

Twins & Multiples

Twin or multiple pregnancies are monitored frequently because they are associated with medical problems, such as high blood pressure. Twin pregnancies are usually shorter than singleton pregnancies, and labour can start a few weeks before your EDD. If the pregnancy is normal, you can give birth vaginally and without medical intervention if you wish. However, some hospitals prefer to induce twins at around 38 weeks. Although the birth of the first baby is usually straightforward, there is a risk the second will move into an awkward position, making an instrumental delivery or Caesarean birth more likely.