Table 1.
Mean birth weight of offspring* by maternal and grandmaternal smoking during pregnancy
|
Mean (SD) birth weight of cohort member (g)
|
Offspring of all women in cohort
|
Offspring of non-smoking mothers in cohort
|
||||
|---|---|---|---|---|---|---|
| Smoking status during pregnancy | No | No | Mean (SD) birth weight (g) | No | Mean (SD) birth weight (g) | |
| Mother of cohort member† | ||||||
| Non-smoker | 8 597 | 3352 (560) | 5240 | 3251 (558) | 3761 | 3300 (530) |
| Before fourth month | 1 074 | 3358 (550) | 713 | 3244 (541) | 486 | 3297 (528) |
| After fourth month | 4 818 | 3181 (581) | 3075 | 3211 (551) | 1858 | 3298 (528) |
| Total | 14 489 | 3295 (572) | 9028 | 3237 (554) | 6105 | 3299 (529) |
| Cohort member | ||||||
| Non-smoker | — | — | 6105 | 3299 (529) | — | — |
| Before fifth month | 720 | 3281 (563) | ||||
| After fifth month | 2203 | 3048 (577) | ||||
| Total | 9028 | 3237 (554) | ||||
*
All birth weights made to correspond to first born females by subtracting increase for males or greater parity.
†
Data on cohort member's birth weight by smoking in mother presented for all cohort members with birth data. Other numbers are based on participants with full data on smoking (cohort member and mother) and birth characteristics (cohort member and offspring).