title: Are women carrying "basketballs" really having boys? Testing pregnancy folklore.
abstract: BACKGROUND
  Antenatal ascertainment of fetal sex is a common feature of modern pregnancies. Women who opt not to learn fetal sex typically employ a variety of methods to forecast it. This study investigated the validity of prevalent folklore used to identify fetal sex before birth.
  
  
  METHODS
  One hundred four pregnant women, who did not know the sex of the fetus, were administered a questionnaire to explore their perceptions of fetal sex and the basis for these predictions.
  
  
  RESULTS
  Fetal sex was not systematically related to the shape of the woman's abdomen, prevalence of morning sickness, or comparisons with previous pregnancies. However, women who had more than twelve years of education correctly predicted fetal sex greater than chance (71% correct), in contrast to less educated women (43% correct). Contrary to expectations, women whose forecasts were based on psychological criteria (i.e., dreams or feelings) were more likely to be correct than those employing prevalent folklore criteria (i.e., the way a woman was carrying the pregnancy).
  
  
  CONCLUSIONS
  In general, women were not good predictors of fetal sex. The mechanisms that promote maternal accuracy in predicting fetal sex for highly educated women are unknown. It is reasonable to expect that maternal perceptions of fetal sex contribute to the process of fetal attachment.
authors.affiliation: Johns Hopkins University, School of Hygiene and Public Health, Department of Population and Family Health Sciences, Baltimore, MD 21205, USA.
authors.forename: D F
authors.initials: DF
authors.lastname: Perry
authors.forename: J
authors.initials: J
authors.lastname: DiPietro
authors.forename: K
authors.initials: K
authors.lastname: Costigan
mesh_terms: D000328:Adult; D001294:Attitude to Health; D004522:Educational Status; D005260:Female; D005495:Folklore; D005544:Forecasting; D006801:Humans; D016015:Logistic Models; D008297:Male; D011237:Predictive Value of Tests; D011247:Pregnancy / Q000523:psychology*; D015203:Reproducibility of Results; D012732:Sex Determination Analysis / Q000592:standards*; D011795:Surveys and Questionnaires