Smoking is another controllable health factor that negatively impacts not only general health, but reproductive health in profound ways. Smoking accelerates the naturally occurring decline in ovarian function that comes with age (brings on menopause sooner), as is also a toxin to gametes (eggs and sperm). Miscarriage rates are higher in smokers compared with non-smokers. Most importantly, the decision to quit smoking is one health factor that is under our control, but success is achievable only if the goal is indeed set. An excellent resource on the subject can be found here. Nicotine substitutes and smoking-cessation medications such as Chantix® or Wellbutrin® may be used when trying to conceive. Ideally these medications should be stopped with positive pregnancy testing.