A variety of other factors may impact the initiation and duration of breast feeding, including infant temperament, breast-feeding difficulties, social/partner support for breast feeding, and breast-feeding self-efficacy. Interestingly, further information one recent study showed that smoking cessation mediated the relationship between smoking cessation treatment and duration of breast feeding (Higgins et al., 2010). Thus, breast feeding and smoking cessation may have a reciprocal influence, such that breast feeding promotes smoking cessation and smoking cessation prolongs breast feeding. Alternatively, a third unidentified variable such as partner or family support may influence both smoking cessation and breast feeding. It is possible that women who maintain breast feeding for 8 weeks are more likely to possess other characteristics that facilitate postpartum smoking cessation.

Future studies are needed to discriminate between possible confounding variables that are predictive of both breast feeding and smoking cessation (e.g., concerns about health of the infant) and variables that are hypothesized to occur as a result of breast feeding and have a positive influence on smoking cessation (e.g., positive influence of oxytocin on affect, desire to avoid exposing nursing infant to nicotine). Mediation analyses may be conducted to identify potential mechanisms of the relationship between breast feeding and smoking cessation, and more complex conceptual models may be evaluated using a structural equation modeling approach. It is important to emphasize that the risks of smoking while breast feeding to the infant (e.

g., infant exposure to nicotine and tobacco smoke) may not outweigh the risks associated with formula feeding and smoking (e.g., Sudden Infant Death Syndrome, respiratory and ear infections; for a discussion see American Academy of Pediatrics Committee on Drugs, 2001). Thus, breast feeding may remain beneficial and appropriate for many women who relapse to smoking, and strategies may be employed to minimize infant nicotine exposure among women having difficulty with smoking cessation. For example, smoking immediately after breast feeding Cilengitide allows more time for the nicotine and other chemicals to leave the breast milk before the next feeding. Women may also reduce their overall level of smoking to minimize infant nicotine exposure. The transdermal nicotine patch may be another option for breast-feeding women attempting to quit smoking, as research has indicated that breast-feeding infants are exposed to less nicotine when the low-dose transdermal nicotine patch (7 mg) is used, compared with continued smoking or the use of a higher dose nicotine patch (21 mg; Ilett et al., 2003).