Influence of smoking on outcome of COH and IUI in subfertile couples

Aim: To evaluate the influence of smoking on the outcome of COH and IUI in subfertile couples. Patients and methods: We reviewed the medical files of all consecutive women, age ≤ 35 years, attending our infertility clinics over an eigth-year period. Data on patient age, smoking habits, and variable related to infertility-treatment were collected from the files. Results: A total of 2,318 cases were evaluated: 1,803 in nonsmoking patients (n = 679) and 515 in smokers (n = 206). The smokers used significantly more gonadotropin ampoules and gained a thinner endometrium on the day of hCG administration than the nonsmokers (p < 0.016 for both). There were no between-groups differences in patient age, duration of gonadotropin stimulation, number of follicle >14 mm in diameter, or E2 levels on the day of hCG administration. Conclusion: Smokers undergoing COH with IUI required a significantly higher gonadotropin dosage than nonsmokers in order to achieved a comparable pregnancy rate.