Longitudinal study of women with negative cervical smears according to endocervical status.

A longitudinal study of 20,222 women who received negative cervical smear reports in 1987 showed that the incidence of definite or equivocal cervical intraepithelial neoplasia (CIN) was not significantly different between those whose first smear lacked an endocervical component and those whose smear included an endocervical component. The incidence of definite cytological evidence of CIN was significantly lower in women whose first smear did not include an endocervical component. It is concluded that women whose smears are reported as negative but lack an endocervical component should not be rescreened any earlier than women with negative smears that include an endocervical component.