OBJECTIVES There is a paucity of data into foetal outcomes for infants born to women with Sickle Cell Disease (SCD). Customised growth charts have been demonstrated to be better at identifying unhealthy small babies than population-based growth charts. Our objective is to analyse the mean birth weight and customised birth weight centiles of infants born to mothers with SCD compared to those for infants born to non-haemoglobinopathy (HbAA) mothers. DESIGN Retrospective cohort study SETTING London hospital POPULATION Singleton pregnancies in women with SCD compared to a HbAA control population of women. Deliveries occurred between 24 and 41 completed gestational weeks. METHODS Eligible deliveries were selected from the hospital's electronic Obstetrics database (Terranova Healthware). Data were extracted on the following maternal parameters: Body Mass Index, ethnicity and the number of previous births; and infant parameters: sex and gestational age at birth. These data were used to generate a customised birth weight prediction which was compared to the infant's actual weight at birth using the UK Gardosi Bulk Centile Calculator. Main outcome measures Birth weight and customised birth weight centiles. RESULTS The birth weight and birth weight centiles were analysed for 88 women with SCD (50 Sickle Cell Anaemia; 38 Haemoglobin C Disease) and 176 controls (HbAA). Statistically significant differences were seen in mean birth weight (P value = 0.004) and mean birth weight centiles (P value = 0.016). CONCLUSION SCD is a risk factor for intrauterine growth restriction.