BackgroundThe aim of the study was to investigate if expecting parents wanted to know the sex of the fetus during ultrasound examination and if they had discussed it with the midwife. Another aim was to explore any interest in sex selection.MethodsA longitudinal survey in early and late pregnancy among 2393 women in Sweden.ResultsAlmost all (95.8%, n = 2289) women had discussed sex determination with the partner before the ultrasound scan, and 57% (n = 1356) of women and their partners wanted to find out the fetal sex. The expecting parents mostly initiated a discussion with the midwife (46%, n = 1088), but 10% (n = 229) stated that the midwives initiated the discussion. Few (5%, n = 118) expressed a potential interest in selecting sex of a baby. Women who were interested in sex determination did not differ from those who were not, with respect to age, origin, education, parity, level of pregnancy planning, or importance of religion, but women who had chosen another fetal diagnostic method were more interested in sex determination and in potential sex selection.ConclusionsHalf of women and their partners wanted to know the fetal sex, and 5% were interested in sex selection. This high interest in sex determination is a challenge, since present national guidelines do not include sex determination as an option.