< AbstractText Label= ? RESULTS ? NlmCategory= ? RESULTS ? > Premature delivery rate was higher ( p = 0.048 ) in the CKC group ( 14/36 , 38.88 % ) than in control group ( 14/68 , 20.5 % ) with a odds ratio ( OR ) of 2.455 ( 1.007 - 5.985 ) ; and premature delivery was related to cone depth , OR was significantly increased when the cone depth was more than