Pregnancy in sickle cell disease in the UK: results of a multicentre survey of the effect of prophylactic blood transfusion on maternal and fetal outcome.

OBJECTIVE: To determine the outcome of pregnancies complicated by sickle cell disease in the UK during 1991-1993 and the effect of prophylactic blood transfusion programmes on maternal and fetal outcome.

DESIGN: A multicentre study.

SUBJECTS: Eighty-one pregnancies complicated by sickle cell disease and 100 pregnancies from women of black African descent without haemoglobinopathies to act as a comparative group. Pregnancies complicated by sickle cell disease were divided by the type of haemoglobinopathy and also by transfusion regimen.

MAIN OUTCOME MEASURES: Antenatal and postnatal complications of sickle cell disease, proteinuric hypertension, preterm delivery, emergency delivery by caesarean section, fetal distress, birthweight, perinatal and maternal mortality.

RESULTS: There were two maternal deaths in the 81 pregnancies and the perinatal mortality rate was 60/1000. Antenatal sickling complications occurred in 46.2% of pregnancies and postnatal sickling complications occurred in 7.7% of pregnancies. Pregnancies complicated by sickle cell disease were significantly more likely to be associated with anaemia, preterm delivery, proteinuric hypertension, birthweight below the 10th centile and caesarean section as an emergency procedure than the comparative group. Severe sickling complications occurred more commonly in the third trimester and there was some evidence that a prophylactic transfusion programme reduced the risk of this. Prophylactic transfusion did not improve obstetric outcome when compared with those pregnancies that were untransfused.

CONCLUSIONS: Sickle cell disease remains a severe complicating factor to pregnancy and perinatal mortality and maternal mortality rates in the UK have increased since last reported. A policy of exchange transfusing all women with homozygous sickle cell disease (HbSS) from 28 weeks gestation is recommended to reduce the risk of maternal complications in the third trimester and puerperium. There remains a role for earlier prophylactic blood transfusion programmes in women with poor obstetric and haematological histories.