Autosomal recessive disorder
Single point mutation in β-Globin chain in haemoglobin.
Diagram explaining the inheritance
Types of sickling conditions
(i)Homozygous sickle-cell disease(HbSS)
(iii)Sickle cell /Thalassaemia
(i)Anaemia due to chronic haemolysis- This is not so marked in HbSC
(iii)acute chest syndrome-pleuritic chest pain,tachypnoea,fever
Sickling crisis in sickle cell trait patients is precipitated by severe anoxia,dehydration or acidosis.
Diagnosis is made by haemoglobin electrophoresis.
Effect of pregnancy on disease
(i) sickle cell crisis is more common on pregnancy
Effect of disease on pregnancy
(i)fertility is generally unaffected.
(ii)Genetic transmission of the condition to the fetus
(iii)Perinatal & maternal mortality is increased
(iv) increased risk fetal complications : miscarriage,intrauterine growth restriction,preterm labour
(v) increased risk of maternal complications: thromboembolism,preeclampsia, abruption,infections(probably due to hyposplenism) like UTI,puerperal sepsis
(ii)Folic acid supplementation 5mg/day
(ii)Folic acid 5mg/day
(iii) Penicillin prophylaxis to prevent pneumococcal infection as a result of hyposplenism.
(iv)partner screening & genetic counselling -Fetal diagnosis by preimplantation genetics in IVF/CVS/Amniocentesis
(v)Regular checking of haemoglobin and mid stream urine
(vi)regular growth scan
(vii) Management of crisis
(b)Pain relief-Morphine.NSAID can cause haemolysis.
(c)early use of antibiotics if infection is likely
(d)need to keep the patient warm ; well oxygenated.Pulse oxymetry & arterial blood gas may be necessary.
(viii)Blood transfusion may be necessary ex: to correct anaemia
(ix) Value of exchange transfusion is not well defined.Theoretically this increase the proportion of haemoglobin A and suppress the bone marrow from producing red cells with HbS. This may decrease the incidence of crisis but need to be balanced against the risks associated with transfusion.
(x) It is important to recognize & treat infection early.
(xi) The following treatments used to increase HbF need further evaluation in pregnancy
(xii) Tourniquet should not be used.
(ii)Epidural analgesia is recommended.
(iii) Sickle cell anaemia is not an indication for caesarean section
(iv)Give oxygen 4-6 l/min
(v)avoid blood loss as much as possible(Active management of third stage)
(i) Dehydration & infection should be avoided.
(ii) Risk assessment for thromboprophylaxis should be done.
(ii) Contraception should be discussed-Even though oral contraceptive pills have been implicated in increased risk of thrombo embolism , this is not based on any evidence.
RCOG guideline on management of sickle cell disease in pregnancy
Interventions for treating painful sickle cell crisis during pregnancy (Review)
Powerpoint on Sickle cell disease in pregnancy
Another presentation on sickle cell disease in pregnancy
Powerpoint on sickle cell disease
• Nelson-Piercy C. Handbook of obstetric medicine. Taylor & Francis; 2002.
• Swiet MD. Medical disorders in obstetric practice. Wiley-Blackwell; 2002.