Associations between prenatal alcohol and tobacco exposure on Doppler flow velocity waveforms in pregnancy: a South African study

Table 2 Quantity and frequency of maternal alcohol and cigarettes used by trimester (timing)

Exposure variables	Trimester one (T1)	Trimester two (T2)	Trimester three (T3)	p-Value T1-T2	p-Value T1-T3	p-Value T2-T3
Drinkers (N)	683	550	268
Non- drinkers (N)	875	997	1287
Drinks consumed per drinking day	4.81 ± 0.16	3.29 ± 0.12	3.04 ± 0.16	p < 0.001	p < 0.001	p = 0.37
Drinks consumed per week	2.08 ± 0.19	0.93 ± 0.08	0.79 ± 0.07	p < 0.001	p < 0.001	p = 0.61
Binge count	1.41 ± 0.10	1.08 ± 0.11	0.64 ± 0.07	p < 0.001	p < 0.001	p = 0.07
Total number of standard drinks consumed	14.6 ± 1.06	10.6 ± 0.84	6.93 ± 0.52	p < 0.001	p < 0.001	p = 0.13
Smokers (N)	952	893	775
Non-smokers (N)	611	653	778
Number of cigarettes smoked per day	5.50 ± 0.15	4.19 ± 0.13	4.16 ± 0.13	p < 0.001	p < 0.001	p = 0.98

Note: Data are presented as mean ± standard error. N represents total count
Non-normal distribution of all three trimesters (using Shapiro Wilk Test), therefore significance tests were all done using Kruskal-Wallis H test. Post-hoc Dunn’s tests significance reported between two trimesters (T). Self-reported drinking and smoking were obtained at the recruitment interview, including up to three prenatal visits after recruitment, using a modified timeline follow-back interview for alcohol and tobacco use. Large standard deviations in the drinking variables are due to the number of drinkers consuming alcohol in some, but not all of the trimesters

ISSN: 1471-2393