OBJECTIVES Primary: to compare sequential and simultaneous breast pumping on volume of milk expressed and its fat content. Secondary: to measure the effect of breast massage on milk volume and fat content.

DESIGN Sequential randomised controlled trial.

SETTING Neonatal intensive care unit, North Staffordshire Hospital NHS Trust.

SUBJECTS Data on 36 women were analysed; 19 women used simultaneous pumping and 17 used sequential pumping.

INTERVENTIONS Women were randomly allocated to use either simultaneous (both breasts simultaneously) or sequential (one breast then the other) milk expression. Stratification was used to ensure that the groups were balanced for parity and gestation. A crossover design was used for massage, with patients acting as their own controls. Women were randomly allocated to receive either massage or non-massage first.

MAIN OUTCOME MEASURES Volume of milk expressed per expression and its fat content (estimated by the creamatocrit method).

RESULTS Milk yield per expression was: sequential pumping with no massage, 51.32 g (95% confidence interval (CI) 56.57 to 46.07); sequential pumping with massage, 78.71 g (95% CI 85.19 to 72.24); simultaneous pumping with no massage, 87.69 g (95% CI 96.80 to 78.57); simultaneous pumping with massage, 125.08 g (95% CI 140.43 to 109.74). The fat concentration in the milk was not affected by the increase in volume achieved by the interventions.

CONCLUSIONS The results are unequivocal and show that simultaneous pumping is more effective at producing milk than sequential pumping and that breast massage has an additive effect, improving milk production in both groups. As frequent and efficient milk removal is essential for continued production of milk, mothers of preterm infants wishing to express milk for their sick babies should be taught these techniques.