Central Australian Aboriginal women's pregnancy, labour and birth outcomes following maternal smokeless tobacco (pituri) use, cigarette use or no-tobacco use: a prospective cohort study

Higher blood nicotine concentrations following smokeless tobacco (pituri) and cigarette use linked to adverse pregnancy outcomes for Central Australian Aboriginal pregnancies

Background

In central Australia, Aboriginal women use wild tobacco plants, Nicotiana spp. (locally known as pituri) as a chewed smokeless tobacco, with this use continuing throughout pregnancy and lactation. Our aim was to describe the biological concentrations of nicotine and metabolites in samples from mothers and neonates and examine the relationships between maternal self-reported tobacco use and maternal and neonatal outcomes.

Methods

Central Australian Aboriginal mothers (and their neonates) who planned to birth at the Alice Springs Hospital (Northern Territory, Australia) provided biological samples: maternal blood, arterial and venous cord blood, amniotic fluid, maternal and neonatal urine, and breast milk. These were analysed for concentrations of nicotine and five metabolites.

Results

A sample of 73 women were enrolled who self-reported: no-tobacco use (n = 31), tobacco chewing (n = 19), or smoking (n = 23). Not all biological samples were obtained from all mothers and neonates. In those where samples were available, higher total concentrations of nicotine and metabolites were found in the maternal plasma, urine, breast milk, cord bloods and Day 1 neonatal urine of chewers compared with smokers and no-tobacco users. Tobacco-exposed mothers (chewers and smokers) with elevated blood glucose had higher nicotine and metabolite concentrations than tobacco-exposed mothers without elevated glucose, and this was associated with increased neonatal birthweight. Neonates exposed to higher maternal nicotine levels were more likely to be admitted to Special Care Nursery. By Day 3, urinary concentrations in tobacco-exposed neonates had reduced from Day 1, although these remained higher than concentrations from neonates in the no-tobacco group.

Conclusions

This research provides the first evidence that maternal pituri chewing results in high nicotine concentrations in a wide range of maternal and neonatal biological samples and that exposure may be associated with adverse maternal and neonatal outcomes. Screening for the use of all tobacco and nicotine products during pregnancy rather than focusing solely on smoking would provide a more comprehensive assessment and contribute to a more accurate determination of tobacco and nicotine exposure. This knowledge will better inform maternal and foetal care, direct attention to targeted cessation strategies and ultimately improve long-term clinical outcomes, not only in this vulnerable population, but also for the wider population.

Note to readers

In this research, the central Australian Aboriginal women chose the term ‘Aboriginal’ to refer to themselves, and ‘Indigenous’ to refer to the broader group of Australian First Peoples. That choice has been maintained in the reporting of the research findings.

Toxic effects of smokeless tobacco on female reproductive health: A review

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Smokeless tobacco use can lead to impairments of ovarian function, morphology, oocyte quality and hormonal regulation.

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Use of smokeless tobacco during pregnancy has adverse health effects on both the mother and fetus.

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Exposure to smokeless tobacco in utero has long term health consequences on offspring.

The habitual consumption of tobacco in its various form is widespread and a serious public health issue globally. In particular, the use of smokeless tobacco has increased substantially due to its easy availability and misconception that it is relatively harmless compared to smoking. Tobacco use has been well established from numerous studies as a causative agent of devastating illnesses such as cancer, insulin resistance, hypertension, acute respiratory disease, osteoporosis, etc. Limited but growing evidence have also suggested its role in adversely affecting reproductive capabilities and outcomes in women of reproductive age and during pregnancy. This paper provides an updated review on available literature regarding the negative effects of smokeless tobacco use on female reproductive health, during pregnancy and its adverse consequences on the offspring. Existing data suggests the association between chronic smokeless tobacco use and impairment of ovarian morphology and function, oocyte quality, hormonal perturbations, fetal development and long-term health effects on the fetus. Improved understanding of these issues can contribute to better awareness of the dangers of smokeless tobacco products.

Central Australian Aboriginal women's placental and neonatal outcomes following maternal smokeless tobacco, cigarette or no tobacco use

OBJECTIVE

To describe the placental characteristics and neonatal outcomes of Central Australian Aboriginal women based on maternal self-report of tobacco use.

METHODS

Placental and neonatal variables were collected from a prospective maternal cohort of 19 smokeless tobacco chewers, 23 smokers and 31 no-tobacco users.

RESULTS

Chewers had the lowest placental weight (460 g) while the no-tobacco group had the heaviest placental weight (565 g). Chewers and the no-tobacco group had placental areas of similar size (285 cm² and 288 cm² , respectively) while the placentas of smokers were at least 13 cm² smaller (272 cm² ). There were two stillbirths in the study and more than one-third (36%) of neonates (newborns) were admitted to the Special Care Nursery, with the chewers' neonates having a higher admission rate compared with smokers' neonates (44% vs. 23%). The cohort mean birthweight (3348 g) was not significantly different between the groups. When stratified for elevated maternal glucose, the chewers' neonates had the lowest mean birthweight (2906 g) compared to the neonates of the no-tobacco group (3242 g) and smokers (3398 g).

CONCLUSIONS

This research is the first to demonstrate that the maternal use of Australian Nicotiana spp. (pituri) as smokeless tobacco may negatively impact placental and neonatal outcomes. Implications for public health: Maternal smokeless tobacco use is a potential source of placental and foetal nicotine exposure. Maternal antenatal screening should be expanded to capture a broader range of tobacco and nicotine products, and appropriate cessation support is required.

Smokeless Tobacco and Its Ill-Effects: Recent Literature Update

According to the Global Adult Tobacco Survey part 2 (GATS-2), approximately 200 million adult Indians consume smokeless tobacco (SLT). Circumvention of SLT product ban has been observed. We conducted a review of the literature to summarize the ill effects of tobacco for the articles published from 2019 to 2020. A systematic search of the databases PubMed (2019 onward) and Web of Science (2019 onward), through February 2021 was done. Search yielded 1,061 articles and after excluding articles based on the inclusion criteria, 37 articles were taken in to consideration. The review shows that differential SLT product has specific odds of oral carcinogenesis. Review also indicates the emerging data of cardiovascular risk due to higher use of SLT products along with its known cause of oral cancer. It also cautions about the adverse consequences of pregnancy associated with SLT use.