Pregnancy outcome after combination laser conization: A case-control study

After combination laser conization, 62 patients had 75 pregnancies progressing beyond 27 weeks of gestation and were compared with 150 pregnancies in control subjects matched for age and parity. The mean birthweight was significantly lower in patients than in control subjects. This difference was due to a higher frequency of premature birth, The premature birth rate was 18.7% after conization, compared with 6.7% in control subjects, There was no difference in the occurrence of preterm premature rupture of the membranes in the two groups. Smoking had a significant influence on the outcome of pregnancy in both univariate and multivariate analysis, and in both patients and control subjects, Multivariate analysis demonstrated both conization and smoking to be significant factors related to the risk of premature birth. The height of cone biopsy was also correlated with the risk of premature birth. The risk of preterm delivery was significantly higher when cone height was >20 mm, A strong correlation between increasing cone height and risk of preterm delivery was demonstrated. Combination laser conization was associated with an increased risk of preterm delivery, but the cofactor smoking was also significant, No other adverse effect of conization on the outcome of pregnancy was observed.