PREGNANCY In Diabetec Women
A woman with diabetes should plan her pregnancy. She should raise her family when she is in her twenties, rather than late in life.
The development of the organs of the foetus lakes place by 10 weeks after the first day of last menstrual period. In order to avoid birth defects in the baby, the conception should take place when diabetes is well controlled for at least preceding three months. Glycated hemoglobin test is valuable in this context, as it indicates control of diabetes in the preceding three to four months.
All diabetic women should take daily folate supplement, at least four weeks before the conception to prevent defects of the nervous system.
A woman with diabetes should report to her doctor as soon as pregnancy is suspected. A tight control of diabetes throughout the pregnancy is of utmost importance.
Initial examination
A complete physical examination including that of the retina is essential. Examination of urine, haemoglobin, kidney and thyroid function are also necessary, for the base line assessment.
Diet
A pregnant diabetic needs extra 300 kcals per day. The protein content of her diet should be more than usual, that is 1.5 g/kg body weight. An additional two cups of milk per day should make up the extra demands of 300 kcals. The supplements of iron, calcium and vitamins should be taken like other pregnant women. Weight reduction should not be attempted during pregnancy.
Since nausea and loss of appetite are common in the first three months of pregnancy, the diet will have to be adjusted in this period.
Alcohol and smoking should be stopped totally.
Insulin
Pregnant diabetics uncontrolled on diet need insulin, human insulin being the type of choice as this produces least antibodies. Usual regimen is short and intermediate-acting insulin, before breakfast and dinner or short or rapid acting insulin before each meal and intermediate acting insulin before dinner. The insulin requirement often diminishes in the first trimester due to reduced food intake but increases from the fourth month of pregnancy till the delivery, after which it returns to the preconception level.
Oral hypoglycaemic agents
These are not given during pregnancy.
Urine testing
In pregnancy, the kidney threshold for glucose is lowered; hence glucose may appear in urine even when blood glucose is not high. Hence, urine testing for glucose has a very limited role in pregnancy. Urine should be tested for ketones. Presence of ketones in morning urine indicates need for more carbohydrates in the diet.
Self monitoring of blood glucose
This is of immense value during pregnancy and ideally has to be done several times a day e.g. fasting and 2 hr after a meal.
Ultra sound scanning
With this technique, it is possible to assess the growth, size, well being and maturity of the foetus to exclude birth defects, to estimate amount of fluid in the uterus, ascertain the expected date of delivery, accurately and safely at individuals during preganancy. An ultra sound is performed between 18th and the 20th week of pregnancy and once in two weeks, after the 26th week.
Care by the team
Throughout the pregnancy, the woman should be under a joint care of a physician and an obstetrician. It is often not realised that the most important member of this team is the pregnant diabetic herself. Her motivation and understanding are essential for the optimum control of diabetes during pregnancy and its successful outcome.
She is seen once in two weeks till the 34th week of the pregnancy and then once a week till the delivery. The optimum glucose levels are 65-90 mg/dl in fasting blood glucose and less than 126 mg, 2 hr after a meal. Control of blood pressure is essential.
The woman should gain about 1.4 kg in the first trimester and 0.25 to 0.5 kg per week, subsequently.
Admission to a hospital may be necessary to ensure optimum control of diabetes. It is often necessary after 32 weeks of pregnancy.
Complications
These are deterioration of kidney function with protein in urine and rise in blood pressure, worsening of retina, ketoacidosis and urinary tract infection. The amount of fluid in uterus is often increased. There is an increased risk of still birth and premature labour. The presence of protein in the urine and rise in blood pressure are more common in a diabetic pregnancy than in a normal pregnancy. The amount of fluid in the pregnant uterus is often increased in diabetic pregnancy. There is some risk of premature labour. Retinopathy due to diabetes may deteriorate during pregnancy.
Timing of delivery
There is a risk of fetal death late in pregnancy, even when diabetes is well controlled. On the other hand, the baby may not be developed properly if the delivery is timed too early. The timing of delivery, therefore, is a question of line judgment. The present trend is to time the delivery in an uncomplicated diabetic pregnancy in the 38th week.
Delivery
Normal delivery is more frequent at present than in the past. Caesarian section is necessary when the weight of the foetus is more than 4.5 kg., when the position of the foetus is abnormal, when a caesarian section was carried out in previous pregnancy. Caesarian section is considered when the mother has retinal disease since straining during bearing down can damage the fragile retinal blood vessels.
It is important to note the pre-pregnancy requirement of insulin. A normal blood glucose level is maintained during labour. This prevents drop of blood glucose level in the newborn. The insulin requirement may fall during labour. After delivery of the placenta, it falls markedly.
New born baby
It is often overweight with a tight skin, liable to birth injuries. The new born baby of a diabetic mother may develop hypoglycaemia, difficulty in breathing, jaundice etc. These are likely to occur when diabetes is not controlled well during pregnancy. These babies may have birth defects of the nervous system, heart, skeleton, kidney etc. These are less common if diabetes is well controlled before conception and in the first three months of pregnancy.
The baby may have to be managed in a special unit if any problems arise.
Breast feeding
Breast feeding is encouraged. Insulin requirement diminishes with breast feeding. The mother is advised to have a snack before nursing the baby.
Follow up examination
As stated already, diabetes or impaired glucose tolerance may occur only during pregnancy to revert to normal after delivery. The blood glucose level should therefore be checked after delivery and of course in subsequent pregnancies. A person with GDM should strive to keep her weight at an optimum level through diet and exercise.
Family planning methods
Since pregnancy itself is a strain on a diabetic woman and since bringing up children is an additional responsibility, she should limit the number of children to the minimum.
The menstrual cycle of diabetic women is often irregular. Hence, the "safe period" method of family planning is not safe for diabetic women.
With the older high dose oral contraceptives, many women used to develop impaired glucose tolerance. With introduction of low dose monophasic (for instance Loette, Ovral) or triphasic, (for instance, Triquilar) oral contraceptives, the change in insulin and glucose levels are of no significance. The use of oral contraceptives does not increase the risk of developing diabetes. Even women with a history of risk factors for diabetes do not seem to be adversely affected. Until overt diabetes develops, it is appropriate for these women to use low dose oral contraceptives. In overt diabetic women, the effect on insulin requirement is neither consistent nor predictable and little if any change occurs with low dose pills.
The use of oral contraceptives may increase the risk of blood clotting in women with diabetes. Therefore, such women should be advised to use other forms of contraception. However, the risk of blood clotting is very minimal with low dose oral contraceptives in women under the age of 35 who are otherwise healthy and who do not smoke. A reliable protection against pregnancy is a benefit for these women, that outweighs the small risk.
Intrauterine contraceptive devices, for example, loop may give rise to pelvic infections if diabetes is uncontrolled.
The barrier method for example, condom and diaphragm with a spermicidal jelly can be used by persons with diabetes.
Sterilization by tying the tubes in women and vas in males, are simple procedures and can be carried out if diabetes is well controlled. Diabetic women should discuss the appropriate method of contraception with their physician and gynaecologist.
Postmenopausal Hormone Replacement Therapy (HRT)
Many post menopausal women suffer from hot flushes, dry ness of vagina and painful sexual intercourse. Moreover, they are at an increased risk of brittleness of bones and unfavourable changes in blood lipids. An increasing number of such women are being started on replacement oestrogen or oestrogen-progestin hormone treatment both as prevention and treatment. HRT does not have an adverse effect on blood glucose, blood lipids or blood pressure. In the absence of other contraindications, in diabetic women, diabetes by itself is not a contraindication for starting such a treatment.