Pregancy – Medical problems

Diabetes

• Fetal exposure to maternal hyperglycaemia causes premature stimulation of beta cells of the islets of Langerhans resulting in fetal hyperinsulinaemia. This also leads to ecessive fetal growth leading to macrosomia
• Women identified as having gestational diabetes have an increased risk of developing it later in life
• Poor diabetic control can lead to congenital malformations

Management of Diabetes in Pregnancy

• If preprandial blood glucose concentration is between 6 to 8 mmol/L, management it via diet
• Insulin therapy begins if levels are above 8mmo/L
• Oral hypoglycaemics are not used because they cross the placenta and stimulate fetal pancreatic beta cells causing fetal hyperinsulinaemia
• Important normoglycaemia is maintained during labour to prevent neonatal hypoglycaemia
• This can be achieved by insulin-dextrose infusions
• Insulin requirements decrease during labour, due to increased glucose required by the uterine muscles
• After delivery there is a rapid decline in insulin sensitivity following delivery of the placenta therefore requiring insulin infusion rate to be reduced
• Pregnancy may accelerate retinopathy in diabetic women
• Diabetic nephropathy increases the risk of pre-eclampsia and growth retardation but will probably not get worse during pregnancy
• Serum AFP and unconjugated oestriol are normally lower in a diabetic pregnancy than normal pregnancy

Obstetric complications

• Pre-eclampsia  test serum urate and creatine concentrations
• Polyhydramnios
• Premature labour

• Poorly controlled diabetes predisposes the fetus to pulmonary and hepatic immaturity which predisposes to neonatal respiratory distress syndrome and jaundice

• During labour there should be continuous CTG monitoring
• Pain relief is important as high levels of pain can cause catecholamine release causing glycogenolysis and hyprglycaemia

• Increased risk of infection following surgical procedures
• Breast feeding decreases insulin requirements

Vitamin D deficiency during Pregnancy

Vitamin D is involved in regulation of calcium metabolism. It does this by;

Increasing calcium absorption from the intestine

Decreasing calcium excretion by the kidney

In conjunction with PTH, mobilising calcium from bon

In utero and childhood, vitamin D deficiency may cause growth retardation, skeletal abnormalities such as neonatal rickets and increased risk of hip fractures later in life

In adults, vitamin D deficiency may exacerbate oestopenia, oestoporosis, muscle weakness and fractures

Toxaemia

Refers to pre-eclampsia, characterised by hypertension, proteinuria and oedema

Becomes evident from the second half of pregnancy

Primigravidae women are more at risk

A history of migraine predisposes to pre-eclampsia

The presence of the trophoblast is necessary for disease but the fetus is not as it can occur in hydatiform mole

Maternal syndrome due to endothelial dysfunction

The proteinuria is associated with impaired glomerular perfusion and filtration, this results in reduced creatine clearance and increased plasma levels of creatine and urea

Lab tests aiding diagnosis during Pregnancy

Hyperuricaemia is characteristic and often precedes proteinuria (>6mmol/L)

Creatine is also measured and increased with pre-eclampsia (>100umol/L)

Clotting system can become disturbed, increased plasma fibrin and raised liver enzymes. Alk phos is always elevated in late pregnancy and gamma-GT only rises late in disease. Therefore the best measurements of liver function are plasma aspartate amino-transferase and lactate dehydrogenase

Platelet levels can fall

Microangiopathic haemolysis leading to a drop in haemoglobin levels, haemoglobulinuria, fragmented RBC on blood film

Liver Disorders during Pregancy

Intrahepatic cholestasis

• Associated with puritis around week 30 and jaundice developing 2 to 4 weeks later
• Mildly raised conjugated hyperbilirubinaemia
• Twice the upper normal limits of aspartate transferase, alanine aminotransferase and alkaline phosphatase
• Fetal distress, premature labour and intrauterine death may occur.
• Elevated levels of bile acid correlate with severity of puritis and fetal distress
• Neonatal vitamin K should be given immediately postpartum

Acute Fatty Liver of Pregnancy

• Typically occurs in obese women in the 3^rd trimester
• May be associations with hypertension, twin pregnancy and a male fetus
• Presenting complaints include, abdominal pain, headache, nausea and vomiting
• Progressive jaundice, encephalopathy, hypoglycaemia, coagulopathy and renal failure can develop
• Histologically a perilobular faty infiltration of the liver is seen
• There is a risk of maternal and fetal death