The final antenatal visit usually occurs by the time 36 weeks have elapsed from the last menstrual period, when the mother-to-be will have come to understand the meaning of the phrase ‘Heavy with child’!
The last four weeks of pregnancy are often an uncomfortable time and apprehension about labor will often increase as the expected date of delivery draws near. Late pregnancy is a time to strive for a tranquil existence.
Cut routine jobs down to a minimum and rest. During the last few, greater attention will be paid to excessive weight gain, swelling of the legs and hands, protein in the urine or a raised blood pressure, since these signs are a warning of .
At the same time, the presentation of the baby is carefully checked to ensure that the head is properly down in the lower part of the uterus-vertex presentation. As well as checking the presentation, the doctor will want to check as far as possible that the head of the baby will pass through the mother’s pelvis. The pelvis has an inlet, a cavity and an outlet. The inlet is the narrowest part of the pelvis so that if the baby’s head will go through the pelvis inlet it will usually go through the cavity and emerge at the outlet.
At about thirty-six weeks, in the case of a woman having her first baby, the head passes through the inlet and into the pelvis to become engaged. The mother-to-be will notice less pressure in the upper part of the abdomen. There is no need for anxiety if your baby’s head has not engaged by thirty-seven weeks. In the first place, engagement of the head at this time usually only occurs with the first baby and, even then, not invariably.
With second and subsequent babies, engagement occurs later and may not take place until labor has actually begun. When the head is not engaged, the doctor may carry out a simple test in which he presses gently down on the baby’s head to see if it will go into the pelvis. The head that is not engaged when the mother-to-be lies down often becomes so when she sits or stands up. This is because gravity pulls the baby’s head down in the direction to which the uterine contractions will make it go when labor starts.
If there is any doubt about the presentation or about the ability of theto pass through the pelvis, the doctor will carry out a vaginal examination. This will enable him to feel the baby’s head and to confirm that it will come down into the pelvis when the mother-to-be sits up or when gentle abdominal pressure is exerted on it.
Occasionally, in cases of real doubt, an X-ray may be ordered so that the exact size of the pelvis can be measured. As a result of these examinations, it will usually be clear that there is not likely to be any problem about the fetus passing through the pelvis and delivering normally.
ANTENATAL 36 WEEKS TESTS
At thirty-six weeks, a repeat blood test will be performed to ensure that you have not become anaemic during the preceding six weeks since the last blood test. In the case ofnegative women a further test for rhesus antibodies will be performed at the same time.
In order to confirm that the placenta is continuing to function well, it may be necessary to check the level of oestriol in the urine or of H.P.L. In the blood. If the fetus does not seem to be growing as it should, and if the tests indicate that the placenta is failing, labor will often be induced in order to deliver the baby from what is becoming an increasingly unfavourable environment.
Apart from the occasional use of an X-ray to measure the size of the pelvis mentioned above X-rays are rarely needed at this stage of the pregnancy. They may sometimes be done to confirm presentation, for example, when the expectant mother is very overweight and the fetus therefore difficult to feel.
The mother-to-be should, of course, know how to tell when labor starts and what to do when it does. In particular, you should know how to contact your husband if you go into labor when he is out at work. If he cannot take you to hospital, you should know, in advance, how to call for an ambulance or a neighbour to transport you.
Hospitals are often confusing places with several entrances, so it is wise for the mother-to-be to know which entrance to use and which ward you are to be admitted to. Most antenatal clinics run a series of classes in relaxation exercises and mother craft which include a visit to the labor and postnatal wards. It is very reassuring to familiarize yourself in advance with the surroundings in which such an important event as your baby’s birth will take place.
A bag containing all essential items that you will need in hospital should be packed and ready by the thirty-eighth week. The clinic will supply you with a check-list of items. The antenatal period may find at any time after that and give way to the climax of pregnancy – having the baby!