Smoking during Pregnancy; An Epidemiologic Study of Knowledge and Behavior in Caucasian Women

Abstract

Introduction. Although it is an easily avoidable lifestyle, tobacco use during pregnancy is an important chronic health care problem, potentially leading to severe pregnancy complications for both mother and infant. Objectives. The purpose of this study was to evaluate the level of knowledge regarding the effects of tobacco smoking during pregnancy. Methods. An online self-report questionnaire was administered using social networks and websites to women who were pregnant or who had recently given birth. Results. 1357 women were eligible to be included in the study. 919 women smoked during their pregnancy, 105 smoked but stopped before pregnancy (former smoker) and 333 never smoked cigarettes in their life. Comorbidities were found in 11.4% of active smokers group, 10.5% (p = 0.758) in the former smokers’ group and 8.1% (p = 0.224) in the never smokers’ group. In addition, 33.8% of active smokers, 42.9% among former smokers and 31.5% of never smokers had a good knowledge about smoking effects. Unfortunately, about 67% of them continued to smoke, even though they knew that nicotine passes into breast milk. The other women reduced the number of cigarettes or even quit smoking, usually with the encouragement and support of close people. Conclusions. Both passive and active smoking during pregnancy is a serious health problem that must be addressed through rigorous health programs, which must include (but not necessarily be limited to) behavioral therapy.

Introduction

Smoking during pregnancy is the leading cause of prenatal morbidity and is associated with an increased risk of complications for both mother and child [1,2]. The global prevalence of smoking during pregnancy is estimated at 1.7%, with the highest prevalence in the European region (8.1%) and the lowest in the African region (0.8%) [3]. Although the prevalence of smoking during pregnancy in high-income countries has decreased substantially in recent decades, the proportion of women who quit smoking during pregnancy remains low [4]. Among the most common complications are placenta previa, placental detachment, spontaneous abortion (for the mother) and premature birth, low birth weight, slow intrauterine growth, sudden infant death syndrome and congenital malformations (for the child) [5,6]. It remains an important risk factor even after birth, being associated with repeated respiratory infections, allergies, asthma and neurobehavioral disorders later in the child’s life [7,8,9]. Despite the known harmful effects and the fact that it is an easy health behavior to change/avoid, smoking during pregnancy still remains a major health problem, as demonstrated by a significant number of studies [10,11,12]. The prevalence of smoking in Romania in the general population is approximately 26.7%, with high values for young women (between 25 and 44 years) of up to 24% [13,14]. New tobacco products such as the electronic cigarette, promoted as an alternative to traditional smoking with tobacco cigarettes, are being increasingly experienced by young Romanian smokers recently. This trend does not depend on gender, classic cigarettes being sometimes associated with e-cigarettes by several family members, all of which create an exciting behavioral alternative for pregnant women [15,16]. The prevalence of smoking in pregnant women and the adverse effects of tobacco on both the mother and the fetus in our country have been evaluated in several studies, with a prevalence ranging from 15% in the Menghea study to 24% in the study by Moga et al. [16,17,18,19]. From the data published so far, there are no studies that specifically evaluate the knowledge of pregnant women regarding the adverse effects of smoking in our country. Knowledge and education are important parts in changing any type of behavior, and anti-smoking campaigns have significantly reduced smoking in the general population. Unfortunately, noting the increased prevalence of smoking among pregnant women, it can be deduced that they do not correctly quantify the harmful effects of smoking (on them and on their child) and/or that younger people are much more addicted to smoking than the elderly. Taking this into account, the main objective of this paper is to evaluate the level of knowledge regarding the effects of smoking among pregnant women, as well as how much smoking influences negatively (for those who continue to smoke) or positively (for those who stop smoking) health status. In addition, the study aims to identify other factors associated with smoking during pregnancy (age, family situation, economic situation, etc.). The exact prevalence of smoking among pregnant women in Romania is unknown, as existing data reflect analyzes from small samples of women and only from some areas of the country (no national data available). Last but not least, this study also aims to evaluate the prevalence of smoking among pregnant women in Romania.

Materials and Methods

This is a cross-sectional study conducted on pregnant women. An online self-report questionnaire, concerning smoking during pregnancy, was applied using social networking and dedicated sites, to women who were either pregnant, either recently gave birth, from November 2016 to February 2017, in Romania. The questionnaire was developed according to the current recommendations of Romanian Society of Pulmonology Guideline for smoking cessation and smoker’s specialist assistance (GREFA), the 2nd edition (2010) and its annexes. To design it, we have also used the expertise acquired within the National Program of Romanian Health Ministry “Adolescent Smoking Cessation 2007–2008”. The study was approved by the Ethics Committee of University of Medicine and Pharmacy “Iuliu Hatieganu”, no: 311/07.06.2016. All participants signed an informed consent to take part to the study. The questionnaire was validated, then smoking behavior among women, their knowledge about the effects of tobacco on their health and information about the child including the child’s health were assessed. It contained demographic data (age, level of education, economic, status, marital status, consumption of alcohol or cigarettes, associated comorbidities), questions about women’s smoking behavior, namely smoking status (active smoker—women that smoked more than 6 months, former smoker—women that gave up smoking for at least 6 months and never smoker—women that smoked less than 100 cigarettes in their entire life), the age of starting smoking, the number of cigarettes smoked/day, if she: has ever been advised to quit smoking, was exposed to passive smoking, knew that smoking could harm her and/or the baby, continued to smoke during the pregnancy, what might convince her to quit smoking and other general questions about pregnancy and the fetus. The comorbidities declared by each respondent were later grouped into the following physiopathological conditions: gastric diseases, lung diseases, heart diseases, hypertension, diabetes, endocrine disorders and others.

In order to select the study participants, the authors searched on social networks for groups that included the target population of the investigation, that is, pregnant women from Romania, using terms specific to the Romanian language. We found 15 social groups for mother and pregnant women: „mamici, gravidute și bebei” (“mums, pregnancy and babies”), „mămici și bebeluși” (“mums and babies”), „gravidute, parinti și copii” (“pregnant women, parents and children”), „sfaturi pentru mamici cu bebici, pitici și burtici” (“advice for mums with babies, midgets and bellies”), „gravide și mamici—sarcina, nașterea și cresterea copilului” (“pregnant women and mums—pregnancy, birth and child rearing”), „clubul mamicilor” (“mums club”), „mamici haioase” (“funny mothers”), „sarcina și mamici burtici și pitici” (“pregnancy and mothers, bellies and dwarfs”), ”mămici , gravidute și pitici” (“mothers, pregnant women and dwarfs”), „mamici și pitici” (“mothers and dwarfs”), „mamici din Cluj-Napoca” (“mothers from Cluj- Napoca”), „burtici și mamici din Romania” (“bellies and mothers from Romania”), „burtici și mamici de pitici: sarcina, alaptare, diversificare, dezvoltare” (“bellies and mothers of dwarfs: pregnancy, lactation, diversification, development”), „gravidute și mamici!” (“pregnant women and mothers!”), „gravidute, naștere şi mamici” (“pregnant women, childbirth and mothers”).

A link with the questionnaire was posted on each group and the participants were asked to complete the questionnaire. An information technology engineer verified the IP of all the eligible questionnaires to make sure that questionnaires received were completed by a single woman and there were not completed by the same women twice. Participation in the survey was anonymous and voluntary. The women were considered eligible if they were: over 13 years old, living in Romania and they were pregnant when completing the questionnaire or had a pregnancy in the past. Exclusion criteria were: male gender, living in other than Romania countries and women that never had babies. The respondents were divided into 3 groups: group I: women that smoked during their pregnancy; group II: women that smoked, but stopped before pregnancy and group III: nonsmoker women. Tobacco consumption was categorized as either light smoking (up to ten cigarettes smoked per day), moderate smoking (11–19 cigarettes smoked per day), or heavy smoking (≥20 cigarettes smoked per day). The prevalence was calculated among the respondent women that declared they smoked during pregnancy.

The statistical analysis was made using EPIINFO version 6.0 of Center of Disease Control and Prevention Center—CDC (Center of Disease Control and Prevention) in Atlanta and the WHO, adapted to the processing from medical statistics and SPSS [19]. The graphs were performed using Harvard Graphics (HGW) program. Frequency intervals, tests of statistical significance were calculated using X2 test. The significance test X2 (hi2) is the most commonly used method for frequency comparisons or proportions, because it can be used in the case of two or more samples. The condition of rejecting the null hypothesis, thus accepting the opposite hypothesis, namely that there is an “unintentional” correlation between the set of parameters, is: p < 0.05. If p < 0.01, the correlation between the two parameters is highly statistically significant. In this study we used the relative risk notion (RR) as it represents the phenomenon studied under conditions of exposure or non-exposure to risk factors, which is generally considered as a power quantification association between factor and disease.

Results

The questionnaire was viewed by 884,400 women (the number of women that were members in all the above—mentioned groups and that looked at the questionnaire—confirmed by our IT specialist that looked for the IP). 1357 women replied and were eligible to be included in the study. 919 women smoked during their pregnancy, 105 smoked but stopped before pregnancy (former smoker) and 333 never smoked cigarettes in their life. The demographic data are showed in

Table 1. Patients’ demographic data.

.

Most of the respondents were married, employed with university degree. The higher the education, the higher the probability of being a never smoker: 60.7% in women with a university degree compared with 27.5% of women that finished high school women and 0.6% of respondents that had just the primary school (p = 0.399). Comorbidities, as declared by each woman in their questionnaires, were found in 11.4% of active smokers group, 10.5% (p = 0.758) in the former smokers’ group and 8.1% (p = 0.224) in the never smokers’ group. Regarding associated diseases, there was no significant difference among the three groups. The most frequent comorbidities were cardiac disease, arterial hypertension and lung diseases (Figure 1).

Passive smoking although was present in all the three groups was higher among active smokers (46.7%) when compared to nonsmokers (33.3%) (p=0.005). Median age for starting smoking was 16.82 years old. No significant difference was seen in the active and former smokers’ group. Median smoking duration was 10.13 years among active smokers compared to 7.37 years in former smokers (p = 0.001). However, no significant differences were found in the pack-years index (PA) in the 2 groups: (54.2% < 5 PA, 29.3%—5–10 PA, >10 PA 16.5) was noted. Among all respondents, 43.21% have quit smoking and 36.8% reduced the number of cigarettes. In the former smokers’ group, 70 (38%) started smoking again, the majority of them being at their first pregnancy. 85% of all respondent women knew that smoking has bad effects on their health and their babies (Figure 2).

Thus, 42.9% among former smokers, 33.8% of active smokers and 31.5% of never smokers had a good knowledge about smoking effects. Despite that, 75% of them continued smoking even though they knew that the nicotine reaches breast milk. The main reason for stopping smoking among pregnant women was family pressure (75.1%). The complications that occurred during pregnancy were: preeclampsia, placenta previa, placenta detachment, abortus imminens, weight loss, and vomiting (

Table 2. Mother’s complications during pregnancy.

).

Preeclampsia was seen in 1.2% of active smokers, 2.2% of former smokers (p = 0.0016) and in 3.21% of never smokers (p < 0.001). The preeclampsia risk was higher in never smokers than in active smokers (RR = 2.748, RA = 0.020). Vomiting was described in 17.8% of smokers, 21.7% of formers smokers (p = 0.344) and 29.3% of never smokers (p = 0.012) (RR = 1.642, RA = 0.115). Complications affecting the babies are described in

Table 3. Babies’ complications at birth.

.

Discussions

The percentage of women that smoked during pregnancy in our study (20%) is comparable with other studies: 12–21% in the United States, 19.2% in Brazil, 23% in Canada with an average consumption of 7.4 cigarettes per day 20–23 [19]. It is also comparable with the reported prevalence by other studies conducted in our country [13,14,15,16,17]. The global prevalence of tobacco use during pregnancy is estimated to between 1–7%. The highest estimated prevalence was in the European Region, namely 30.6% (38.4% in Ireland, 29.4% in Bulgaria, 26% in Spain, 25.2% in Denmark, 22.3% in Italy, etc.), while the lowest prevalence was in the African Region (0.8%) [20,21,22].

In 2018, the estimated of pregnant smokers were 8.1% in Europe and 7.2% in the USA [23,24].

Most pregnant women significantly reduced the number of cigarettes when finding out about their pregnancy [11]. Regarding their knowledge on smoking effects, most women knew that active and passive smoking during pregnancy could harm the fetus (88.1%, 63.3%). In our study, 75% of women knew about the deleterious effects of maternal smoking on both fetal and infant health, nevertheless they continued smoking. Knowledge about the negative effects of smoking during pregnancy was higher at younger, in other study, compared to women over 30, factors that influenced smoking cessation [25].

In ours study the respondents were under 30 ages, a maternal smoking in younger mothers being a major concern. Literature sustains that active smoking women are less educated and less informed about outcomes [26].

However, knowledge and education were related to holding a university degree in most women who were never smokers [19,20,21,22]. A similar situation is encountered in lung cancer patients, where despite of well-known benefits of smoking cessation (in any stage), only 12.9% quit smoking completely after counseling and 50% reduced the number of cigarettes [27]. Of course, smoking cessation medications, which were not provided in several studies, could, in the authors’ opinion, increase the rate of smoking cessation [28,29,30]. Unfortunately, this type of therapy is not applicable to pregnant women. Factors associated with a high use of tobacco during pregnancy in other studies were: young and single mothers, smoking behavior among other family members and entourage, early smoking, increased level of stress, depression, problems during childhood, drug abuse, multiple pregnancies, low education and socioeconomic level [9,19,23]. On the other hand, a higher socioeconomic and educational level, the presence of a life partner, big families, low levels of nicotine dependence are associated with a bigger rate of smoking cessation during pregnancy [19].

For understanding of maternal smoking, additional factors were examined: not having children prior to the current or most recent pregnancy, predicted increased likelihood of quitting smoking [29].

Preterm birth is similar with nonsmokers or with mothers who quit smoking early during pregnancy. Even mothers smoke just 1–2 cigarettes per day, during either the first or the second trimester were at a higher risk of preterm delivery compared with nonsmokers [30].

Bertani and colleagues, also found a high prevalence of active (40.9%) and passive smokers (72%) among pregnant women [27]. One of the most measurable effects of smoking on pregnancy is approximately doubling the risk of delivering a baby with low weight at birth [19]. Birth weight deficits in infants vary between 200 to 327 g, depending on the dose of nicotine administered through tobacco products. Each cigarette smoked per day during pregnancy reduces the baby weight by approximately 10–12 g [28,29].

More and more studies associate preterm birth, lower birthweight, intrauterine growth restriction, transfers to the neonatal intensive care unit, and neonatal intensive care unit admissions, with a dose–response relationship [31]. These findings suggest that there is no safe level or safe trimester for maternal smoking during pregnancy [30].

Apart from these complications, others can appear even after birth (in childhood), in children born to mothers who smoked during pregnancy. They are represented by: respiratory infections, otitis media, asthma, childhood cancer, hearing loss, dental caries, and metabolic syndrome, adverse cognitive and behavioral outcomes were also associated with smoking during pregnancy [32]. Even risk of ADHD (attention deficit hyperactivity disorder), one of the most common mental disorders affecting children with an increased risk of severe mental illness in the adult, is also associated in some research with smoking during pregnancy [33].

Vomiting and nausea in pregnant mothers are linked to high levels of endokinin, an active peptide that is considered to be necessary for healthy placental functions, which is thought to be found in lower-than-normal concentrations in pregnant women who smoke due to different regulatory mechanisms (caused by smoking lung stress secreted endokinin). This may be a bonding factor for pregnant women to find difficult to quit smoking, as the fetal effect would be less visible during the emesis prone phase of pregnancy. Even so, pregnant women were more motivated to modify their lifestyle and health behaviors than at other times in their life [34,35,36].

The rate of smoking cessation during pregnancy is higher than the general population, with 27% and 47% of smokers quitting in the first trimester. Moreover, women who quit smoking in the first trimester of pregnancy have the most chances to maintain smoking cessation and after the birth of the pregnancy, comparing to women who quit in the 2nd and 3rd trimesters of pregnancy [37].

Thus, pregnancy represents a “window opportunity”, or a “teachable moment” for smoking cessation interventions [9,28,38]. The smoking cessation process may be influenced by multiple factors, such as: the type of cessation treatment and the individual characteristics [39,40]. Adding a biological evaluation to the clinical assessment of smokers will give us a more holistic approach of the problem. Current guidelines support the clinic-based “5A” intervention of healthcare providers in all pregnant women: (1) Ask, (2) Advise, (3) Assess, (4) Assist, and (5) Arrange follow-up. Pregnant women who actively smoke should be assessed on this matter and advised to quit at each visit [27].

According to the Theory of Reasoned Action, increased knowledge of adverse outcomes can influence attitudes and beliefs about behaviors; in turn, increased knowledge about health outcomes can influence attitudes, which can increase women’s intention to quit smoking before or during pregnancy [40]. In a second plan, the context of low-middle income countries may predispose to lower compliance to healthy life-style and related behaviors, in all fields, not only regarding smoking prevention and cessation [41,42,43].

In a frequent contact with health professionals during prenatal care, women are more receptive to educational measures, medical information and health promotion, being more receptive to consider smoking cessation. Many pregnant women accept a referral to stop-smoking support. Pregnant women who cannot quit smoking should reduce smoking to less than six cigarettes a day to minimize the negative effects of smoking on the weight of the newborn. Women may be more likely to quit smoking if their partners and/or family members support the act of quitting together [44].

Smoking during pregnancy is, unfortunately, still a common habit in many regions of the world [45], although smoking during pregnancy has an important negative health effect: low birth weight and preterm birth, restricted head growth, placental problems, increased risk of still birth, increased risk of miscarriage. Taking into account all these risks, we believe that an information in this sense to all smoking women who are planning a pregnancy or who are already pregnant should be done systematically. Also, all these women should be helped to quit smoking through national public health programs.

Findings indicate that there is also a need to educate and train providers on recommended approaches for smoking cessation during pregnancy. Many participants who were previously pregnant reported that providers counseled them to cut back rather than quit smoking during pregnancy. Health care providers might incorporate discussions about the timing of smoking cessation during pregnancy (though ideally before pregnancy) and the importance of quitting completely within their counseling sessions. Although a few experts have argued that recommending a reduction in smoking (also known as “harm reduction”) might be more acceptable to some patients than cessation, not enough is known about the potential benefits and/or risks to the pregnant women and infant in using this approach. Increasing knowledge and publicity of the negative health effects of smoking have led to reductions in maternal smoking over the past two decades, although only small reductions have been described in some periods [39].

It’s important to note that some women are not prepared to stop smoking in pregnancy. The Transtheoretical Model of Intentional Behaviour Change can provide a helpful starting point for the categorization of the pregnant smoker [46]. The intention to reduce/eliminate smoking would produce significant health benefits, because it would reduce not only smoking but also the associated economic costs, thus providing pregnant women with obvious arguments for reducing smoking [47].

Regarding the risk of premature birth, a study carried out in the United States of America on more than 25 million young women, for 7 years, it was increased in all pregnant smokers, regardless of the number of cigarettes smoked per day (even to 1–2 cigarettes/day) and/or regardless of the trimester of pregnancy. The conclusions of the study are that all women of reproductive age should be encouraged and supported to quit smoking before planning a pregnancy [48].

Even though existing guidelines for pregnant advised women who smoke to abandon smoking before pregnancy, majority women who smoke before pregnancy continue to smoke during pregnancy or start to quit smoking after becoming pregnant [49].

The American College of Obstetricians and Gynecologists calls the attention of all obstetricians and gynecologists, as well as family physicians, that pregnant women and/or those planning a pregnancy should be asked not only if they smoke, but also about the forms of smoking or nicotine consumption (including smoking cigarettes, using electronic cigarettes or vaping products, hookah, snus, pills, patches and gum). These questions must be asked before planning a pregnancy, during pregnancy, but also in the postpartum period, in order to minimize the risks to the fetus and the newborn related to the mother’s smoking. Pregnant women should be informed of the significant perinatal risks associated with tobacco use, including orofacial clefts, fetal growth restriction, placenta previa, abruptio placentae, premature rupture of membranes before labor, low birth weight, increased perinatal mortality, ectopic pregnancy and decreased thyroid function, i.e. the risk of congenital hypothyroidism [50].

Women who smoke during the fertile period, as we have shown above, must be constantly supported to abandon smoking, but also the consumption of alcohol or other drugs, and the provision of continuous support and the addressing of psychosocial stress factors in the postpartum period are necessary to ensure continued smoking cessation success [48,49,50].

Our study has some limits. The first relates to female respondents who may have been more likely to give socially favorable answers, particularly regarding quitting smoking during pregnancy, rather than being completely honest. The second is that predicted behavior does not always reflect actual behavior, so respondents may have said they would quit smoking if their doctor gave them specific reasons to quit, but may not have appreciated the subsequent difficulty real in giving up this vice. Furthermore, respondents might not have understood the hypothetical nature of the question asking about advice from a healthcare provider. Also, it was an online questionnaire, so we were not able to reach to other women like those who do not use social media. And unfortunately, not all eligible women responded because it was a large sample. However, despite its numerous limitations our study has some strength: it’s a heterogeneous sample (includes also adolescent mothers) from all the cities in Romania, giving an estimate about the prevalence of smoking among pregnant women in our country. This is the first study, to our knowledge, to evaluate the knowledge about tobacco effects on health among pregnant women.

Conclusions

Among the pregnant women evaluated, there was a high prevalence of both active and passive smoking during pregnancy, despite an increased knowledge of its deleterious effects. Interestingly, although a higher education is associated with a lower change of ever smoking behavior, a satisfying knowledge among pregnant women about tobacco effects does not reduce its use during pregnancy. As revealed by answers in our survey, the main reason for these educational deficiencies among pregnant women’ behavior seems to be due to lack of specialized approach in this field by their family doctors, gynecologist, midwives and other categories of staff in charge with follow-up of their 9 months pregnancy status. As such, health policies must be improved and even adapted according to mentalities (for the most vulnerable situations) and social status, especially in low- and middle-income countries, because they are currently considered one of the categories of smokers with the highest risk (women with a low education level, lower income, and single mothers).