Table 4.
Results summary for NRT and reproduction/development—birthweight or low birthweight
| CAF no.a | References | Comparisonb | Endpoint | Casesc | Statistic (95 % CI)d |
|---|---|---|---|---|---|
| 4 | Lassen et al. (2010) | – | Birthweight change (g) per week NRT use | – | 0.25 (−2.31 to 2.81)e |
| 8 | Gaither et al. (2009) | Prescribed/recommended NRT versus not | Low birthweight | NA | 1.49 (0.79 to 2.82)f |
| 10 | Wisborg et al. (2000) | Nicotine versus placebo patch | Birthweight difference (g) | – | 186 (35 to 336)g |
| Low birthweight | 4/11 | 0.4 (0.1–1.1)i | |||
| 13 | Pollak et al. (2007) | Any NRT + CBT versus CBT only | Birthweight difference (g) | – | −71 (−283 to 141)h |
| 14 | Oncken et al. (2008) | Nicotine versus placebo gum | Birthweight difference (g) | – | 337 (155 to 519)h |
| Low birthweight | 2/16 | 0.11 (0.03–0.47)i | |||
| 15 | Swamy et al. (2009) | Any NRT + CBT versus CBT only | Low birthweight | 4/0 | 4.48 (0.25–81.63)i |
| 16 | Coleman et al. (2012b) | Nicotine versus placebo patch | Low birthweight | 56/43 | 1.38 (0.90–2.09)j |
| 17 | El-Mohandes et al. (2013) | Nicotine patch + CBT versus CBT only | Birthweight difference (g) | – | 206 (−98 to 510)h |
| Low birthweight | 3/4 | 0.75 (0.19 to 3.03)i | |||
| 18 | Berlin et al. (2014) | Nicotine versus placebo patch | Birthweight difference (g) | – | 50 (−71 to 172)g |
| Low birthweight | 27/33 | 0.82 (0.51–1.31)i | |||
| Meta-analysis of low birthweight (n = 7) | Fixed effect | 1.01 (0.78–1.31) | |||
| Random effects | 0.81 (0.48–1.39) | ||||
| Heterogeneity p | p = 0.01 | ||||
| Weighted analysis of birthweight difference (n = 5) | Mean | 142 (−53 to 336) | |||
| Heterogeneity p | p = 0.11 | ||||
a CAF critical assessment form. CAF 4 is a prospective study, CAF 8 is a cross-sectional study, and the rest are clinical trials
b CBT cognitive behavioural therapy
cExposed/unexposed cases. NA data not available. ‘–’ not applicable
dFor differences in birthweight the mean is shown (exceptionally in one study exposure per week of NRT use), and for low birthweight the odds ratio (OR) or relative risk (RR) as indicated
eBirthweight was noted not to vary significantly by type of NRT used. Also using the Danish National Birth Cohort, Zhu et al. (2014) (CAF 7) reported a clear reduction in birthweight associated with maternal smoking, but no significant reduction associated with NRT use, regardless of whether the father smoked
fAdjusted OR in smokers estimated from data provided
gUnadjusted mean difference
hUnadjusted mean difference estimated from data provided
iUnadjusted RR estimated from data provided
jOR adjusted for recruitment centre