BACKGROUND: External (to the fetus) stressors may act together with maternal factors as well as fetal and placental factors to increase the risk of stillbirth. Data published in 2011 indicate non-left side sleeping positions, particularly the supine one, is such a stressor; we do not know, however, if this new knowledge has influenced the choice of sleeping position among pregnant women.

METHODS: Using a web-based questionnaire made available at the home page of the Swedish national infant foundation we collected information on sleeping positions among women who gave birth to a stillborn baby between 2000 and 2014.

RESULTS: The questionnaire was completed by 583 women. About one third of the women reporting their sleeping position stated that they lay down on their the left side when going to bed, and another third reported lying down as often on the left as on the right side. Figures for typically going to bed on the left side the 4 weeks preceding the stillbirth was as follows: 72 (30 %) of 242 between 2011 and 2014 and 86 (27 %) of 313 between 2000 and 2010. Among the 240 women who remembered their position when waking up on the day the stillbirth was diagnosed, 63 (26 %) reported a supine position.

CONCLUSION: Our data indicate that one third of the women went to bed on the left side the month before the stillbirth. The data are consistent with the notion that efforts in Sweden to advise women to lie on their left side when going to bed may decrease the rate of stillbirth.