Breech presentation

Breech presentation is common in early pregnancy and decreases with advancing gestational age, as most babies turn spontaneously to a cephalic presentation before birth.[3]Scheer K, Nubar J. Variation of fetal presentation with gestational age. Am J Obstet Gynecol. 1976 May 15;125(2):269-70. http://www.ncbi.nlm.nih.gov/pubmed/1266909?tool=bestpractice.com [4]Nassar N, Roberts CL, Cameron CA, et al. Diagnostic accuracy of clinical examination for detection of non-cephalic presentation in late pregnancy: cross sectional analytic study. BMJ. 2006 Sep 16;333(7568):578-80. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1570002 http://www.ncbi.nlm.nih.gov/pubmed/16891327?tool=bestpractice.com The prevalence at term in singleton pregnancies is 3% to 4% of all births.[1]Cunningham F, Gant N, Leveno K, et al. Williams obstetrics. 21st ed. New York: McGraw-Hill; 1997.[2]Kish K, Collea JV. Malpresentation and cord prolapse. In: DeCherney AH, Nathan L, eds. Current obstetric and gynecologic diagnosis and treatment. New York: McGraw-Hill Professional; 2002. The prevalence prior to term at various gestations is as follows:[3]Scheer K, Nubar J. Variation of fetal presentation with gestational age. Am J Obstet Gynecol. 1976 May 15;125(2):269-70. http://www.ncbi.nlm.nih.gov/pubmed/1266909?tool=bestpractice.com

• 33% of births less than 28 weeks' gestation

• 14% of births at 29 to 32 weeks' gestation

• 9% of births at 33 to 36 weeks' gestation

• 6% of births at 37 to 40 weeks' gestation.