Abstract

Pregnant women who were intending to breast-feed were recruited to a prevalence study of inverted and non-protractile nipples. Among the 3006 women examined, the overall prevalence was found to be 9.8% (95% CI 8.8–10.9%). Of the factors investigated, the three which appear to cause a reduction in the prevalence of inversion and nonprotractility are: increasing gestation; increasing maternal age; and previous breast-feeding, each of these having an effect which is independent of the others. Parity of itself appears to have no effect. The mechanism of the influence which these factors have upon prevalence may be in part biological but other influences which have bearing on a woman's choice of infant-feeding method are also likely to be relevant. The authors consider that antenatal examination for poor protractility should be abandoned. If the examination is conducted it should be delayed until the third trimester and need not include those who have successfully breast-fed previously.