Sickle cell disease and pregnancy.

Pregnancy is a particularly risky period in the life of patients with sickle cell disease (SCD). Physiological changes during pregnancy increase the risk of vaso-occlusive crises (VOC), acute chest syndrome, venous thromboembolic events, and infections. This concerns haemoglobin (Hb) S/C and S/β-thalassaemia patients as much than S/S or S/β-thalassaemia patients. SCD also increases the risk of obstetrical complications, such as preeclampsia, in utero foetal death, preterm delivery mostly induced, and intrauterine growth restriction. Thus, pregnancy should be planned and closely monitored by a multidisciplinary team involving obstetricians and sickle cell disease specialists. Before pregnancy, the parents should also be informed about the risk of transmission of this autosomal recessive disease, and the father should therefore be prescribed haemoglobin electrophoresis. Treatments have to be revised when planning pregnancy: hydroxyurea (HU) should be stopped as soon as pregnancy is suspected or confirmed. Preventive blood transfusion is not systematic, but is recommended in the case of a pre-existing transfusion program prior to pregnancy, severe pre-existing organ damage, severe obstetric history, and severe or repeated crises during follow-up, especially in patients taking HU before. Despite the risks of prematurity, systematic administration of corticosteroids for foetal lung maturation is not recommended due to the risk of maternal vaso-occlusive event. Although more frequent, due to obstetrical and maternal complications, caesarean section is not systematic, in the absence of maternal contraindications. It is advisable not to exceed the term of 39 weeks of amenorrhoea. Post-partum follow-up is recommended, particularly because of the risk of thromboembolism.