Randomized trial of a "stage-of-change" oriented smoking cessation intervention in infertile and pregnant women.
To assess a "stage-of-change" oriented smoking cessation intervention for infertile and pregnant women, compared with standard of care.
                Randomized controlled trial.
                Three university teaching hospitals in Hamilton, Ontario, Canada.
                Infertile women at their first visit to a tertiary referral infertility clinic (n = 94) and new patients seeking pre-natal care (n = 110) who had smoked >/= 3 cigarettes in the past six months.
                A three to five minute scripted intervention and booklet specific to the woman's "stage-of-change" in the smoking continuum, versus standard of care. Exhaled carbon-monoxide (CO) monitoring was used to validate exposure in both groups.
                Delta "stage-of-change" and rate of maintained cessation at 12 months post follow-up.
                Intervention and control were similarly effective for infertile women: the rate of maintained cessation rose significantly from 4% to 24% over twelve months, with a mean delta "stage-of-change" 0.28. In prenatal women, neither approach was effective. Maintained cessation did not significantly change from 0 to 12 months (19% to 18%). Mean delta "stage-of-change" declined by -0.62.
                For infertile women, basic information describing the impact of smoking on fertility, along with exhaled CO monitoring and a more intensive intervention were both highly effective. In pregnant women neither approach was beneficial, with some evidence of post-partum relapse.
No RCTs were located that assessed the effects of preconception advice on the chance of a live birth or other fertility outcomes in people who perceived that they may be infertile and were investigating the possibility of medical treatment to address subfertility. Given the lack of RCTs evaluating the effectiveness of preconception lifestyle advice for people in the afore-mentioned population, this review cannot provide guidance for clinical practice in this area. However, it does highlight the need for further research into this important subject.