Oxford Handbook of Midwifery (49 page)

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baby and taking the baby outside the home. Women need support and reassurance during this time.

1. Royal College of Obstetrics and Gynaecologists (1998). The management in pregnancy of women with epilepsy. Available at: M http://www.nhshealthequality.org/nhsqis/files/maternityservices_
   pregnancywithepilepsy_spc6RH5_DEC97.pdf (accessed 22.2.11).
   
2. Stokes T, Shaw EJ, Juarez-Garcia A, Camosso-Stefinovic J, Baker R (2004).
   Clinical guidelines and evidence review for the epilepsies: diagnosis and management in adults and children in primary and secondary care
   . London: Royal College of General Practitioners.
   
3. Bagshaw J, Crawford P, Chappell B (2008). Problems that mother’s with epilepsy experience when caring for their children.
   Seizure
   17
   , 42–8.
   

   CHAPTER 10
   Medical conditions during pregnancy
   

   188‌‌
   

   Thromboembolic disorders
   

   Venous thromboembolism (VTE) is the obstruction of a blood vessel, usually a large vein, with thrombotic material carried in the blood from its site of origin to block another vessel.
   

   Several factors are associated with an increased risk of VTE during pregnancy:
   

   • Increasing maternal age
     
   • Increasing parity
     
   • Operative delivery
     
   • Immobility and bed rest
     
   • Obesity
     
   • Dehydration
     
   • Thrombophilia.
     

     According to Lewis
     ¹
     it is particularly important to recognize the risk of VTE in the mother with a raised BMI of 30 or above. The risks are present from the first trimester onwards. In the years 2003–2005, 41 women died of VTE and 16 of these women had a BMI of 30 or over.
     ¹
     

     Thromboembolic disorders can be categorized as:
     

   • Superficial thrombophlebitis
     
   • Deep-vein thrombosis
     
   • Pulmonary embolism.
     

     Superficial thrombophlebitis
     

   • This is caused by the formation of a clot in a superficial varicose vein as a result of stasis and the hypercoagulable state of pregnancy.
     
   • Varicose veins commonly occur in pregnancy because of increased venous pressure in the legs and the action of progesterone.
     
   • A red, inflamed area appears over the vein, which feels firm on palpation.
     

     Management
     

     •
     Encourage the woman to mobilize wearing TEDS.
     

   • Instruct her to raise her leg when sitting and give her exercises to be
     

     carried out daily.
     

   • Local warming applications may provide additional comfort.
     
   • The inflammation should subside within a few days and the clot in the superficial vein causes no immediate hazard.
     
   • Observe the woman closely for signs of DVT.
     

     Deep-vein thrombosis
     

   • A less common but more serious condition.
     
   • A clot forms in the deep vein of the calf, femoral, or iliac veins and there is a risk that fragments may break off and travel through the circulation, causing embolus.
     
   • The woman will complain of pain in the leg and there may be oedema and a change in colour in the affected leg.
     
   • The calf or leg is painful on palpation and dorsiflexion of the foot causes acute pain.
     

THROMBOEMBOLIC DISORDERS

189

Management

Pulmonary embolism

• Acute chest pain due to ischaemia in the lungs
  
• Difficulty breathing (dyspnoea)
  
• Blue discoloration of the skin (cyanosis)
  
• Coughing up blood (haemoptysis)
  
• Pyrexia
  
• Collapse.
  

  Management
  

of the clot. Patients with a minor embolus may present with less specific symptoms, such as fever, cough, or pleuritic pain. Commence anticoagulant therapy and continue until symptoms resolve.

1
Lewis, G (ed.) (2007).
The Confidential Enquiry into Maternal and Child Health (CEMACH). Saving Mothers’ Lives: Reviewing Maternal Deaths to Make Motherhood Safer
—
2003–2005
. The 7th report on Confidential Enquires into Maternal Deaths in the United Kingdom. London: CEMACH.

CHAPTER 10
Medical conditions during pregnancy

190‌‌

Principles of thromboprophylaxis

Following publication of the latest report of the Confidential Enquiries into Maternal Deaths in the UK in December 2007,
¹
the recommenda- tions of the RCOG on thromboprophylaxis in the antenatal, intranatal, and postnatal periods may be followed until new guidelines have been approved. A summary of the recommendations appears in the report and can also be found in RCOG guidelines.
²

The risk factors for VTE include:

• Previous VTE
  
• Congenital or acquired thrombophilia
  
• Obesity (BMI 35 or above. Those with a BMI of 40 or above are at high risk)
  
• Parity of 4 or above
  

• Gross varicose veins
  
• Surgical procedures during pregnancy or the postnatal period
  
• Hyperemesis
  
• Dehydration
  
• Severe infection
  
• Pre-eclampsia
  
• Long-haul travel
  
• >4 days of bed rest.
  

  The main recommendations for thrombo-prophylaxis are:
  ¹
  

• All women should be screened for risk factors for VTE in early pregnancy and again if admitted to hospital or on development of other problems
  
• Women with a previous VTE should be screened for thrombophilia
  
• In all pregnant women immobilization should be minimized and dehydration avoided
  
• Women with previous VTE should be offered thromboprophylaxis with low-molecular-weight heparin (LMWH) in the postnatal period.
  

  •
  Women with recurrent VTE, or VTE with a family history of VTE in a first-degree relative, or with previous VTE and thrombophilia, should
  

  be offered LMWH antenatally and for 6 weeks post partum.
  

• Women with three or more persisting risk factors should be considered for LMWH for three to five days postnatally.
  
  1. Lewis, G (ed.) (2007).
     The Confidential Enquiry into Maternal and Child Health (CEMACH). Saving Mothers’ Lives: Reviewing Maternal Deaths to Make Motherhood Safer
     —
     2003–2005
     . The 7th report on Confidential Enquires into Maternal Deaths in the United Kingdom. London: CEMACH.
     
  2. Royal College of Obstetricians and Gynaecologists (2009).
     Thrombosis and Embolism during Pregnancy and the Pinerperium, Reducing the Risk
     . Green Top 37. London: RCOG. Available from: http://
     www.rcog.org.uk/womens-health/clinical-guidance/reducing-risk-of-thrombosis-greentop37a. (accessed 22.2.11).
     

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  CHAPTER 10
  Medical conditions during pregnancy
  

  192‌‌
  

  Thyroid disorders
  

  Pregnancy makes special demands on the thyroid gland which enlarges due to the influence of oestrogen. The hormone hCG has thyroid stimulating properties and may even cause hyperthyroidism in excessive amounts.
  

  There are four main disorders of the thyroid affecting pregnancy:
  

• Iodine deficiency
  
• Hypothyroidism
  
• Hyperthyroidism
  
• Postpartum thyroiditis.
  

  Iodine deficiency
  

• Leads to a condition called goitre. In mothers who have goitre and are also hypothyroid, 30% of pregnancies will result in spontaneous abortion, stillbirth, or congenital abnormalities.
  
• This condition is rare in the UK as iodine is present in a variety of foods such as shellfish, saltwater fish, mushrooms, and soya beans.
  
• When iodine deficiency occurs in the first trimester this may lead to developmental failure of the central nervous system, resulting to severe learning difficulties, deafness, and spasticity.
  
• In the second and third trimester the iodine deficiency may lead to an infant being born with hypothyroidism. This consists of large tongue, dry coarse skin, umbilical hernia, and lethargy. The condition responds to iodine or thyroid hormone replacement and prognosis is related to when the condition first started.
  

  Hypothyroidism
  

  Symptoms
  

• Hypothermia and intolerance to cold
  
• Decreased appetite, weight gain, and constipation
  
• Dry rough flaky skin and hair loss
  
• Impaired concentration and memory
  

  •
  Extreme fatigue.
  

  Effects on pregnancy
  

• Spontaneous abortion and stillbirth rates are higher in this group.
  
• Symptoms should be observed for and thyroid function measured in any pregnant woman in whom there is a suspicion of dysfunction.
  
• If diagnosed, treatment with replacement thyroid hormone is prescribed.
  

  Hyperthyroidism
  

  Symptoms
  

• Increased temperature and heat intolerance
  
• Restlessness and insomnia
  
• Increased appetite, weight loss, and diarrhoea
  
• Exophthalmos—protrusion of the eyeball.
  

THYROID DISORDERS

193

Effects on pregnancy

Postnatal thyroiditis

Around 11–17% of women develop postnatal thyroid dysfunction between 1 and 3 months post delivery. It resolves spontaneously in two-thirds of those with this condition. The remainder pass into a hypothyroid state and although most recover, a small number continue to be hypothyroid.

Recommended reading

Casey BM, Leveno KJ (2006). Thyroid disease in pregnancy.
Obstetrics and Gynecology
108
(5), 1283–92.

The Endocrine Society (2007). Management of thyroid dysfunction during pregnancy and postpartum: an Endocrine Society clinical practice guideline.
Journal of Clinical Endocrinology and Metabolism
92
(8), S1–S47.

Nicholson WK, Robinson KA, Smallridge RC, Ladenson PW, Powe NR (2006). Prevalence of postpartum thyroid dysfunction: a quantitative review.
Thyroid
16
(6), 573–82.

CHAPTER 10
Medical conditions during pregnancy

194‌‌

Renal conditions

There are a number of changes in the urinary tract as a result of pregnancy.

• Plasma volume expansion of 30–50% is conserved by the kidneys.
  
• There is an increased frequency of micturition in the first trimester due to the growing uterus compressing the bladder within the pelvis. This effect is noticed again in the third trimester as the bladder displaces when the fetal head engages.
  
• As a result of the hormonal effect on the renal tubules the renal threshold for glucose is lowered independently of blood glucose levels.
  
• There is dilation and enlargement of the ureters under the influence of progesterone leading to an increased risk of urinary stasis, obstructed urine flow and ascending infection.
  
• Pregnancy does not make renal function worsen in women who are normotensive and who have normal kidneys.
  
• Proteinuria, hypertension, or impaired renal function present at conception determines fetal prognosis.
  

  Renal disorders in pregnancy can range from asymptomatic bacteriuria to end stage renal disease requiring dialysis. Every pregnant woman with renal disease should be classed as a high risk pregnancy especially when impaired renal function or hypertension is present.
  

  For optimal management a multidisciplinary approach is essential and care should be in a facility with experience of high risk pregnancies, a neonatal intensive care unit, and the woman’s care coordinated by an obstetrician and nephrologist from the outset.
  

  Glomerular nephritis
  

  This condition can follow a streptococcal infection and occurs in response to an abnormal antibody–antigen reaction.
  

  Signs and symptoms
  

  •
  Oedema
  

• Aching loins
  
• Dyspnoea
  
• Bradycardia
  
• Oliguria
  
• Haematuria.
  

  Treatment
  

• Antibiotics
  
• Restricted protein diet
  
• Restricted fluids until diuresis begins
  

  Overall fetal loss is 21% with a preterm delivery rate of 19%.
  

  Nephrotic syndrome
  

  This can follow glomerular nephritis or be a result of diabetes or renal vein thrombosis.
  

  Signs and symptoms
  

• Marked proteinuria
  
• Oedema
  

  RENAL CONDITIONS
  

  195