Complications in pregnancy

Pregnancy is a natural event, and it usually ends with a healthy mother and normal baby. While the great majority of women have no major problems, there is a degree of risk involved – about 20 per cent experience some kind of complication. However, modern antenatal care now does a great deal to spot potential problems and deal with them before they put the life of the mother or baby at risk. (This section deals with the range of major complications, but see also the sections dealing with and for information on these conditions in relation to pregnancy).

Toxaemia (pre-eclampsia)

This happens to one in 10 women in the last weeks of pregnane}-. The blood pressure is raised, protein substances leak into the urine, and the retention of water in the tissues leads to swelling of the body or a sudden weight gain. It is commoner in a first prcgnancy than in later ones, and in an older mother than a younger. It also occurs more frequently if the mother is carrying twins. Nobody knows its precise cause, but it is probably related to cells from die placenta leaking into the mother’s circulation, causing damage to the kidney filtering mechanisms and the walls of the small blood vessels.

If the condition is allowed to proceed unchecked, the blood pressure slowly creeps up to levels that are dangerous to the baby. The baby, living on the other side of the placenta, depends entirely upon the flow of blood from the mother that reaches the placental membrane. If the blood pressure is raised, there maybe some damage either to that membrane or the blood vessels supplying it. The baby is then at risk because the exchange of nutrients and oxygen from the mother’s blood is poorer than normal. Additionallv. In labour the condition may lead 10 an acme shut-off of oxygen.

The mother is affected too. Her fluid retention increases so that there may be sudden weight gain or puffiness of the ankles, the hands and the face. If the condition is not checked it could lead to a more dangerous state; she could have eclampsia – a series of dangerous fits -recurring even’ few minutes. 11’s very rare for the problem to get this far nowadays, because die toxaemia is usually diagnosed and treated early on.

Because of the large load they are earning around, many women in later pregnancy have swollen ankles – this is particularly noticeable in the afternoon. But if the swelling occurs in the morning, it should be reported to the doctor. Some pregnant women may also notice that their hands are becoming puffy.

Tests to diagnose toxaemia

A rise in the blood pressure reading -taken at a regular antenatal visits – will bring the problem to the attention of the doctor. This does not usually happen until the last four or weeks pregnancy, but in rare cases it may be earlier. In addition to checking blood pressure, a sample of early morning urine can be tested at each antenatal visit. This will show if the kidney filters are damaged. If the doctor diagnoses toxaemia he can do certain tests to check that the baby is progressing well. He may investigate the growth of the baby by ultrasound scans, or he may check the baby’s well being by estimating oestrogen producdon. This hormone, made mainly by the baby and the placenta, is passed into the mother’s body, then excreted in her urine. Checking urine samples to assess the full 24-hour production of oestrogen is a good guide to the health of the unborn child. The best treatment for toxaemia is bed L rest. This allows a reduction in blood pressure and a slight increase in the blood supply to the uterus and growing baby. In the earlier stages a woman can rest in bed at home, provided it’s fairly peaceful. If she has an active young child to look after this could be difficult, but pre-eclampsia is commonest in a first pregnancy. Should the condition become worse, she may be admitted to hospital for more rest, and drugs can be given to help reduce the blood pressure level further. If the tissue swelling becomes painful, other treatments can be given to cause the kidneys to excrete more water, so reducing the tension.

If, despite this, the toxaemia persists, most doctors advise that the baby should be delivered as soon as it reaches full term. They usually recommend inducing labour when the neck of the womb is ripe, or if the condition worsens very sharply, performing a Caesarean section. This will remove the baby from the hazardous environment of raised blood pressure inside the uterus, and produce good results for mother and baby.

Rhesus incompatibility

A woman with a rhesus negative blood group who conceives a rhesus positive child produces a potentially dangerous situation. Blood from the rhesus positive baby can pass across the placenta into the mother’s circulation and ‘sensitize’ her natural defence mechanism to make antibodies. These antibodies will destroy rhesus positive cells. Fortunately, this passage of the blood from baby to mother occurs most commonly at the time of delivery and so there is not enough time to affect the first baby. But if his mother is sensitized into producing the antibodies, these will damage the blood cells of any rhesus posidve baby she carries in future.

The antibodies may cause the red cells in the baby’s blood to break down so the baby becomes anaemic – and makes increased amounts of a bile substance from the breakdown of iron pigments in his red cells. Whilst the baby is in the uterus, the excess bile is shunted across the placenta, but once the baby is born his own liver is too immature to cope with this heavy load, so he rapidly becomes jaundiced. In extreme cases, this might cause brain cell damage, so without treatment, the baby could be spastic.

There are no symptoms of rhesus incompatibility that the mother will notice. It is one of the hidden conditions which is only detected by proper antenatal care ana testing. The doctor detects rhesus incompatibility by checking the mother’s blood group early in pregnancy. If she is rhesus negative, he then examines her blood further for rhesus antibodies. These will not be present in the first pregnancy, but if he finds them in a later pregnancy he will do further tests to assess the rdegree of the problem.

The whole treatment of rhesus incoin-~patibility depends upon blood tests, and tests of the fluid around the baby. Blood tests will show whether the baby is being affected by rhesus incompatibility, and the doctor will want to assess the speed at which the antibodies build up to see how serious a problem it is for the baby. Once 20 weeks of pregnancy have passed, some of the fluid surrounding the baby in the uterus can be removed and checked for bile breakdown products. If the rate of bile breakdown is very rapid, the doctors may give the baby a blood transfusion.

A very fine needle is passed into the uterus and through the baby’s stomach wall. Via this needle a transfusion of compatible blood is given to the baby to tide him over for a few weeks when his own red blood cells are being broken down by the antibodies. The transfusion may have to be repeated several times, until the baby is delivered.

Once the baby is delivered, special blood tests are done immediately to check the degree to which he is affected. If this is serious, an exchange transfusion takes place- the baby’s blood is slowly removed in small quantities, each fraction being replaced by compatible blood that will not break down. Any rhesus negative mother who gives birth to a rhesus positive baby is now routinely given a special injection soon after delivery to prevent sensitisation. This usually prevents rhesus problems with the next baby. Since this technique became widespread, ‘rhesus babies’ are now rare.

Severe vomiting

About two thirds of women have some vomiting in early pregnancy, but they are quite able to continue their usual activities. About one in 1000 have such severe vomiting that the woman becomes dehydrated and, unless this is controlled, her levels of fluids, nutrients and vitamins are greatly reduced.

This excessive vomiting can happen at any time of the day or night, often going on continuously for many hours at a time. The woman can retain no food or fluid and loses weight. She may obviously be ill, and if the condition is left untreated rfcr some time she may develop jaundice. Hospital treatment is advisable. An ~~intravenous drip is usually required to bypass the overactivity of the intestine; this will restore fluid and salt balance and provide essential vitamins. Anti-vomiting drugs are also given.

Vaginal bleeding in early pregnancy

Any bleeding in pregnancy after the last menstrual period is abnormal and needs to be investigated. The blood might not look bright red, for if blood stays in the upper vagina for a few hours before leaking out, it looks more dark brown in colour. If there is only a small amount of brown blood loss, contact the doctor the next morning. If the bleeding is more rapid and accompanied by pain, ring the doctor immediately and retire to bed.

Sometimes bleeding in early pregnane}’ is due to a polyp or erosion of the surface tissue of the cervix – the neck of the womb. But in both of these cases, the bleeding is actually quite slight and often no more than a brown discharge. Usually a polyp or cervical erosion will be left alone until the pregnancy is over, as they are not a serious threat either to the mother or to her baby.

Miscarriages

The commonest cause of bleeding is a threatened miscarriage. The egg has been implanted in the uterus for some weeks but is not secure, and so when the uterus makes a few contractions it causes bleeding. If the condition worsens and there is more bleeding, the cervix starts to open and the embryo is passed out- a complete miscarriage. In a few cases the embryo dies at this early stage, but the bleeding and miscarriage don’t actually occur until a few weeks later.

When the doctor examines the woman he checks to see if the cervix is open. If it is closed, there is only a threat to miscarry at this stage. The best treatment for this is bed rest. By resting the whole body, the uterus is rested too, and in most cases the threat recedes, and a normal pregnancy follows. The doctor may prescribe a mild sedative to help the woman sleep.

If the cervix is open, a miscarriage is inevitable, and die woman will be admitted to hospital because the bleeding can be very severe. As nothing can be done to save the pregnancy, an operation is carried out to evacuate the lining of the uterus (similar to a D and C).

Ectopic pregnancy

If die embryo is implanted in die Fallopian tube instead of in the uterus, there may be a small amount of bleeding accom-

Vaginal bleeding in late pregnancy

This can be a sign of a serious threat to the mother and baby. Any bleeding in the last months of pregnancy should be reported immediately to the doctor. It’s important to note the amount of bleeding and whether there is any pain associated with it; also, keep any pad which has been soaked in blood, as this may prove useful to the doctors when they are diagnosing the problem.

As with bleeding earlier in pregnancy, a local cause such as cervical erosion or polyps could be responsible, and very rarely it can be a sign of a generalized blood disease in the mother. More often, however, it’s caused by a problem with the placenta either becoming detached or being in the wrong position.

Ectopic pregnancy

Panied by symptoms of pain and a tender area on one or other side of the uterus. The embryo will not develop because the (-..Fallopian tube cannot support a baby. [ treatmentj This is an urgent matter, requiring immediate surgery, for there is a risk that there will be heavy bleeding, and the woman may become very ill. The surgeon has to remove the embryo and the tube in which it is implanted. Most women recover from the operation very well and go on to have a normal baby- the other Fallopian tube is still intact.

Detached placenta

The placenta is the exchange station between the blood supply of the mother and the unborn baby. Sometimes it develops quite normally, but then prematurely separates from the wall of the uterus, causing bleeding. This is a very rare occurrence, but when it does happen it resents a major threat to the babv, ecause its oxygen supply is disrupted. There is also a serious threat to the mother from severe shock.

Urgent hospital treatment is required.

Occasionally, if the uterus is tense and the mother is very shocked, a doctor may call out a team of hospital doctors to perform an emergency blood transfusion before moving her. Once in hospital, an ultrasound monitor will be used to check the baby’s heart rate. If the baby is mature a Caesarean section may be performed to avoid further risk to the mother and baby. If the bleeding is less severe, it may be a case for hospital rest for a short time followed by an induced delivery when the mother is in better condition.

Placenta praevia

Normally the placenta is situated on the upper part of the uterus, lying above the baby’s head. But sometimes, if the fertilized egg implanted lower down in the uterus, the placenta develops below and in front of the baby’s head. This is known as During the last two months of pregnancy, the stretching and softening that takes place in the lower part of the uterus and the cervix causes some degree of separation between the ~ placenta and uterus- resulting in bleeding.

The mother will be admitted to hospital. ~~’if the symptoms suggest it is not a detached, normally sited placenta, the doctors will carry out tests, such as an ultrasound scan, to see precisely where the placenta is lying. Every effort is made to carry on the pregnancy until the baby is maturejbeyond 36 weeks). Then, if the placenta is very low lying, the doctors may deliver the baby by a Caesarian operation, because a normal vaginal delivery would involve a great deal of bleeding and the loss of the baby. If the placenta is lying low, but to one side, a normal delivery may be all right, but the doctor will usually first examine the woman under anaesthetic in the operadng theatre to make sure this is the position. The membranes surrounding the baby will then be burst so that a vaginal delivery can go ahead.