Pregnancy and Diabetic Nephropathy

Today, it is just as possible for a woman with Type 1 diabetes to become pregnant and have a healthy baby as for someone without diabetes. This was not always the case. Previously, because there were fewer methods for achieving good blood sugar control.

Women with diabetes not only risked increased complications during their pregnancy and labor, but their children were frequently susceptible to deformities and health problems after birth. The fact that this risk no longer exists for diabetic women is, above all, thanks to the possibility of intensive diabetes management before and during the pregnancy, as well as better observation and treatment during and after the birth.

What to do before getting pregnant:

  • Diabetes control should already be optimal. Then the risk of a birth defect, which may arise during the first few weeks of pregnancy when the blood sugar level is high, can mostly be avoided. This means, however, that the timing of the pregnancy should be planned as accurately as possible, so that sufficient time is available to establish good blood sugar control through intensive therapy.
  • The retina in the eye should be examined. If there are no signs of retinopathy, checks every three months are sufficient. If retinopathy is already present, this gets worse in half of such affected women during pregnancy. Sometimes, early laser treatment of the damaged eye before or even during the pregnancy may be advisable. The development of the eye damage should be closely monitored by an ophthalmologist.
  • Protein excretion and blood pressure should be tested before and at the start of the pregnancy.

What to do during the pregnancy:

  • Blood sugar levels must be tightly controlled, to keep the risk to mother and child as low as possible. For pregnant women, the limits are particularly strict: the blood sugar level should stay just below 90 mg/dl and if possible should not exceed 120 mg/dl after eating.
  • Blood pressure, urine (tests for protein excretion and for urinary tract infections) and blood should be monitored regularly. Body weight is also important. If this increases very rapidly and by too much, it may be evidence of a dangerous complication that threatens both mother and child, known as EPH syndrome.

EPH stands for oedema (‘edema’ in American English; water retention in the tissues), proteinuria (increased protein excretion in the urine) and hypertension (high blood pressure).

  • The development of the baby should be monitored regularly using ultrasound.

Even when a woman already has diabetes-induced kidney damage, a successful pregnancy and the birth of a healthy child are still possible. In principle, the same rules for management should be followed as for all other women with Type 1 diabetes, but the presence of diabetic nephropathy can complicate the pregnancy and endanger both the mother and child.

If micro-or macroalbuminuria is present before the start, protein excretion will usually increase during the pregnancy. Rises of fourfold or more are possible – but in most cases this should not be a reason to worry. After the pregnancy, the rate of protein excretion nearly always falls again.

It is important, however, to test the rate of albumin excretion regularly during the pregnancy because an unusually high value may warn of the onset of the feared complication, EPH syndrome. A woman who has microalbuminuria before her pregnancy has a 12% greater risk of developing EPH.

If this is not recognized early or is not treated, it can be life-threatening for the mother and her baby. Blood pressure also rises significantly in most pregnant women who have impaired kidney function – if it wasn’t already high because of the nephropathy. It must be lowered again and today there are many drugs available to achieve this.

ACE inhibitors, which are usually the first choice drugs for patients with nephropathy, may not be given during pregnancy. This is because they may have adverse effects on the organ development of the child. The same is true for calcium antagonists.

Thus, a woman who has been taking any of these drugs should change her regime before getting pregnant. Of course, it is particularly important to measure your blood pressure yourself at home, every day during your pregnancy. Long-term (24- hour or overnight) measurements are also advisable.

What happens to kidney function during pregnancy? This is a very important question. As a woman with diabetes who already has early kidney impairment, must I count on having to undergo dialysis after the birth? Up to now, very few studies have addressed this.

They have shown that in about half of women there is no worsening of kidney function during pregnancy. In the other half, kidney function deteriorates but improves again after labor. Which group you belong to is strongly dependent on the state of your kidneys before the pregnancy:

  • If your kidney function is only lightly impaired, with a serum creatine concentration of less than 2 mg/dl, the risk of it worsening seems to be slight.
  • If you already have significant kidney damage, you must expect further impairment, which may even continue after the pregnancy. In a study from the 1980s and 1990s, one in four women with diabetic nephropathy needed dialysis within three years of giving birth.

Children of women with diabetic nephropathy often develop more slowly during the pregnancy and have a lower birth weight. The degree of growth retardation depends above all on the kidney function of the mother.

To avoid threatening complications in women with diabetic nephropathy, labor is often induced early or the child is born by Caesarean section. Although these babies more frequently need to be kept in intensive care, the survival rates in specialized centers are today just as good as for children of non-diabetic mothers.