Abstract
Background
Recent publications show that smoking and alcohol use among adolescents with unplanned pregnancy is increasing and the causes need to be further studied.
Objective
To determine the association between living in a non-intact family household and the presence of smokers and consumers of alcoholic beverages in the adolescents' environment with smoking and consuming alcoholic beverages in adolescents with unplanned pregnancies.
Methods
A cross-sectional study was carried out among 785 pregnant adolescents, aged 13–19 years. Data was collected by trained interviewers using a self-administered questionnaire. The association was determined using multivariate logistic regression analysis.
Results
In adolescents with unplanned pregnancies, the prevalence of active smoking was 21.2% and of alcohol consumption, 41.5%. The percentage of smoking at home was 57.4% and alcohol consumption, 77.5%. Approximately, 80.3% of adolescents with unplanned pregnancies had friends who smoked and 90.6% consumed alcoholic beverages. Multivariate logistic regression analysis shows that having friends who smoke or who consume alcoholic beverages is the most important risk factor for substance use in adolescents with unplanned pregnancies. Smoking and alcohol consumption at home are not associated with smoking in adolescents with unplanned pregnancies.
Conclusion
Socializing with friends who smoke and/or consume alcoholic beverages constitutes the most important risk factor for substance use among adolescents with unplanned pregnancies.
Keywords: Family, unplanned pregnancy, substance use, adolescents
Introduction
Smoking and consumption of alcoholic beverages constitute an important health problem worldwide and have been related with a great number of negative effects, including laryngeal carcinoma, cirrhosis of the liver, chronic pancreatitis and development of healthrisk behaviors such as sexual activity at an early age, and unplanned pregnancies in adolescents.1–6
According to the World Health Organization, in many developed and developing countries, a great number of pregnancies in adolescents is reported every year, of which up to 80% are unplanned.7–12 The negative effects induced by unplanned pregnancies include an increase in maternal-infantile morbidity and mortality, loss of self-esteem, depression, anxiety, familial conflicts, dropping out of school, interruption of life projects, premature incorporation into the labor force, and maintenance of the poverty cycle.6,7,8,9 Even more, pregnant teens tend to recognize their pregnancies later than adult women and are more likely to be engaged in binge drinking and drug use early in their pregnancies, thus exposing the fetus to alcohol.13,14,15,16
There is evidence showing that smoking and consuming alcoholic beverages are associated with the development of unplanned pregnancies.17,18 Recent studies show that, the prevalence of smoking and alcohol consumption, is higher in adolescents who develop unplanned pregnancies and the causes that lead these young people to use these types of substances are unclear.1,2
Several theories have been examined in an attempt to identify the factors that influence smoking behavior and alcohol use in adolescents; no consensus has been reached.19,20 One significant proposal is that the absence of one or both biological parents (non-intact family), or the presence of parents and friends who smoke and consume alcohol within the adolescents' environment can be responsible for the development of smoking and consumption of alcoholic beverages.21,22,23,24 However, to our knowledge, the association between family structure, tobacco and alcohol use at home and by friends, with smoking and alcohol use in adolescents with unplanned pregnancies has not been studied.
It is clear that living in a non-intact family household and the presence of smokers and consumers of alcohol in the adolescents' environment can exert different effects on the development of their behavior, possibly favoring the acquisition of certain habits or risky behaviors, particularly smoking and consumption of alcoholic beverages.19,20,24,25
One priority for the control of smoking and alcohol use is to identify, but above all to understand, the degree to which some familial and social circumstances influence the development of certain health-risk habits and behaviors in adolescents with unplanned pregnancies. Accordingly, this study was designed to determine the association between living in a non-intact family household and the presence of smokers and consumers of alcoholic beverages in the adolescents' environment with smoking and consuming alcoholic beverages in adolescents with unplanned pregnancy.
Methods
Design, participants, and setting
We conducted a cross-sectional study based on a population research. A total of 3,500 female adolescents aged 13–19 years who had participated in a prior, broader study with the primary objective of detecting and preventing health-risk habits and behaviors, were invited to participate in the present study.26 Of these, 370 adolescents were excluded in the final sample due to not completing the questionnaire or reporting incorrect information that impeded its analysis. Thus, we analyzed data on 3,130 adolescents. From these, 785 (25%), were pregnant.
The selection criteria for this study was: adolescents, aged 13 — 19 years, that were pregnant and without disease. The sample corresponds approximately to 35% of the total population of female adolescents in our region. Data was analyzed in 2013.
The female adolescents included in the study were residents of an urban area of North-Eastern Mexico. This zone is localized in the southern part of the State of Tamaulipas, on the Gulf of Mexico coast and 542 km North-West of the Mexican capital, and is composed of the cities of Tampico, Madero, and Altamira. The three cities share an area of 1,492.7 km2 and have a population of 706,771 inhabitants.
The study was approved by the Ethics Committee of the Faculty of Medicine of Tampico of the Autonomous University of Tamaulipas.
Procedure
For data collection, we constructed a self-administered questionnaire based on others previously utilized.27,28 Questionnaire completion was carried out with specially trained personnel. Training of personnel was conducted through presentations and workshops with the objective of unifying criteria with regard to certain questionnaire items, including those related with the diagnosis of health-risk habits and behaviors such as unplanned pregnancy.
Those adolescents meeting the inclusion criteria were invited to participate in the study. The trained personnel in research studies contacted all patients and provided a verbal explanation of study. These personnel were available on site during the application of the questionnaire and provided additional information when necessary. The adolescents were informed that their participation was voluntary, they would remain anonymous, and all information would be kept confidential. All the participants provided written informed consent prior to the survey. Adolescents had the right to withdraw from the study at any time without penalty, even after they had finished responding to the questionnaire. The time required to complete the questionnaire was approximately 30 minutes. A total of 89.42% of participants answered the questionnaire.
Completion of the questionnaire was performed at the adolescents' homes, recreational areas, public sites, schools, and at institutions providing health services.
For application of the instrument in the schools and Health Centers, the permission of the authorities was sought and obtained.
In the conurban zone comprising the three cities, there are 28 Health Centers that depend on the Health Ministry of the State of Tamaulipas. An Adolescent Health Care Module is installed at the most important and best equipped Health Center. For application of questionnaires, participation was requested and female adolescents aged 13–19 years were identified, pregnant and not pregnant, these arrived at these centres to ask for medical care.
Pregnant adolescents and those diagnosed with any other pathology were referred for care of their disease(s) to the corresponding Medical Service Unit.
Data collection
To determine the level of understanding of questionnaire items, we conducted two pilot studies. In each of these studies, 20 individuals were interviewed with 15-day difference between them. Questions were closed, multiple choice, and binomial, grouped in four blocks. In the first block, we included questions to document the age of the adolescents, anthropometric measurements, civil status, if they had children, schooling, history of health-risk habits, and behaviors such as active smoking, consumption of alcoholic beverages, and sexual activity. Similarly, we documented the adolescents' sexual education level and communication with their parents on sexuality themes. Additional information was collected on the health-risk habits and behaviors of the female friends with whom the study participants socialized most frequently.
In the second block of the questionnaire, we gathered family information, such as the civil status of the parents, whether the adolescent lived with one or both biological parents, etc.
In the third and fourth blocks, we requested information on the adolescent's mother and father, respectively, regarding age, occupation, schooling, smoking and alcoholism, etc.
Measures
Unplanned pregnancy
Information related with this dependent variable was collected by means of two questions: First, the adolescent was asked whether she was pregnant at present. For the analysis in this study, this group of adolescents was identified as 1. Pregnant, and 0. Not pregnant.
Subsequently, in the case of being pregnant, the adolescent was asked: Prior to becoming pregnant, did you plan your pregnancy? This nominal variable was codified as: 1 = Unplanned pregnancy if the adolescent's response was “NO” and 0 = Planned pregnancy if the adolescent's response was “YES”.
Active smoking
Measurement of this variable was obtained from participant response to the following: A. Do you smoke? Response options were (1) Yes, at least one cigarette daily, (2) Yes, but less than one cigarette a week, (3) Yes, at least one cigarette per month, (4) Yes, but only on special occasions, and (5) No, I do not smoke. We considered these adolescents as active smokers when they reported to smoke at least one cigarette a week. This independent variable was coded as 1 = Smoker, and 0 = Non-smoker.
Consuming alcoholic beverages
Measurement of this variable was obtained from the participant's response to the following: A. Do you consume alcoholic beverages? Response options were: (1) Yes, at least once daily; (2) Yes, but less than once a week; (3) Yes, at least once per month; (4) Yes, but only on special occasions, and (5) No, I do not consume alcoholic beverages. We considered these adolescents as consumers of alcoholic beverages when they reported consumption of alcohol at least once a week. This independent variable was coded as 1 = Consumes alcoholic beverages, and 0 = Doesn't comsume alcoholic beverages.
Family structure
Based on the presence or absence of one or both biological parents, this variable was coded as follows: 1 = Non-intact family if the adolescent lived with one or with no biological parent or 0 = Intact family if the adolescent lived with both biological parents.
Smoking at home
Smoking at home was considered present when at least one of the adolescent's parents smoked. This independent variable was coded as 1 = Smoking at home, and 0 = No smoking at home.
Alcohol consumption at home
Alcohol consumption at home was considered present when at least one of the adolescent's parents consumed alcoholic beverages. This independent variable was coded as 1 = Alcohol consumption at home, and 0 = No alcohol consumption at home.
Friends who smoke
We considered the presence of friends who smoke when the adolescents responded affirmatively that some or the majority of best girlfriends smoke. This variable was dichotomized as 1 = Friends who smoke, and 0 = Friends who do not smoke.
Friends who consume alcoholic beverages
We considered having female friends who consume alcohol when the participants responded that some or the majority of their best female friends consumed alcoholic beverages. This variable was dichotomized as 1 = Friends who consume alcoholic beverages, and 0 = Friends who do not consume alcoholic beverages.
Analyses
The prevalence of non-intact family, active smoking, at home and friends' smoking and drinking was determined to compare adolescents with unplanned and planned pregnancy. The association between independent variables with smoking and consumption of alcoholic beverages in adolescents with unplanned pregnancy was determined by means of a multivariate logistic regression analysis. Adjusted odds ratios (AOR) and their 95% confidence intervals (95% CI) were calculated. In evaluating the association, we adjusted for the following confounders: employed mother, and the relationship of the adolescent with her mother. Data were analyzed by means of the SPSS ver.10.0 statistical package software. Any value of p <0.05 was considered significant.
Results
From the 785 of pregnant adolescents identified in this study, the prevalence of unplanned pregnancy was 59.5%.
In the group of adolescents with unplanned pregnancy, the percentage of active smoking was 21.2% and consumption of alcoholic beverages, 41.5%. The prevalence of smoking and alcohol consumption at home was 57.4% and 77.5%, respectively. Approximately, 80.3% of adolescents with unplanned pregnancies had friends who smoked and 90.6% of these consumed alcoholic beverages. Table 1 shows that the percentages of active smoking, smoking and alcohol consumption at home, and friends who smoke or consume alcoholic beverages was higher in adolescents with unplanned pregnancies compared with adolescents who reported planned pregnancies.
Table 1.
Distribution of the frequencies of the adolescents studied with relation to risk factors for unplanned pregnancy.a
| Pregnancy (n = 785) | |||||
| Planned (n = 318) |
Unplanned (n = 467) |
||||
| n | (%) | n | (%) | X2 | |
| Age (years) | |||||
| <15 | 13 | (4.1) | 25 | (5.4) | 0.75 |
| Active smoking | 39 | (12.3) | 99 | (21.2) | 1.26* |
| Alcoholic beverage consumption |
105 | (33.0) | 194 | (41.5) | 1.15* |
| Non-intact family | 159 | (50.0) | 157 | (33.6) | 0.75 |
| Smoking at home |
140 | (44.0) | 268 | (57.4) | 1.24* |
| Alcohol consumption at home |
192 | (60.4) | 362 | (77.5) | 1.43* |
| Friends who smoke |
236 | (74.2) | 375 | (80.3) | 1.16* |
| Friends who consume alcoholic beverages |
270 | (84.9) | 423 | (90.6) | 1.27* |
The results are expressed by number (%).
P <0.05; p >0.05.
Smoking
A higher percentage of adolescents who smoke (Table 2) was found in youngsters with unplanned pregnancies who resided in a non-intact family (28.0 vs. 13.2%), who had friends who smoke (25.3 vs. 15.7%), or who consumed alcoholic beverages (23.2 vs. 14.1%) compared with adolescents with planned pregnancies who resided in an intact family and who did not have friends who smoke or consume alcoholic beverages.
Table 2.
Multivariate logistic regression analysis of factors that are associated with the smoking among adolescents with unplanned and planned pregnancy
| Smoking | ||||||
| Unplanned pregnancy (n = 467) |
Planned pregnancy (n = 318) |
|||||
| Yes/No | % | Adjusted OR 95% CI)a |
Yes/No | % | Adjusted OR (95% CI)a |
|
| Non-intact family | ||||||
| Yes | 44/113 | 28.0 | 1.77(1.112.84)* | 21/138 | 13.2 | 0.85(0.43–1.69) |
| No | 55/255 | 17.7 | 18/141 | 11.3 | ||
| Smoking at home | ||||||
| Yes | 58/210 | 21.6 | 1.30(0.81–2.08) | 20/120 | 14.3 | 1.38(0.70–2.71) |
| No | 41/158 | 20.6 | 19/159 | 10.7 | ||
| Alcohol drinking at home | ||||||
| Yes | 80/282 | 22.1 | 1.33(0.76–2.36) | 25/167 | 13.0 | 1.15(0.57–2.34) |
| No | 19/86 | 16.1 | 14/112 | 11.1 | ||
| Friends who smoke | ||||||
| Yes | 95/280 | 25.3 | 8.46(3.00–23.86)* | 37/199 | 15.7 | 7.49(1.76–31.87)* |
| No | 4/88 | 4.3 | 2/80 | 2.4 | ||
| Friends who consume alcoholic beverages | ||||||
| Yes | 98/325 | 23.2 | 13.86(1.87–102.52)* | 38/232 | 14.1 | 8.25(1.10–61.95)* |
| No | 1/43 | 2.3 | 1/47 | 2.1 | ||
Adjusted for the variables employed mother and the relationship of the adolescent with her mother. AOR = Adjusted Odds ratio; 95% CI = 95% Confidence interval.
P <0.05; p >0.05.
Results of the multivariate logistic regression analysis showed that living in a non-intact family household (Adjusted OR [AOR] = 1.77; 95% CI = 1.11–2.84), is associated with the habit of smoking in adolescents with unplanned pregnancies, but not in those with planned pregnancies (AOR = 0.85; 95% CI = 0.43–1.69). On the other hand, the presence of friends who smoked or who consumed alcoholic beverages was significantly associated with smoking in both groups of adolescents, in those with unplanned pregnancies (AOR = 8.46; 95% CI = 3.00–23.86 and AOR = 13.86; 95% CI = 1.87–102.52) and in the group with planned pregnancies (AOR = 7.49; 95% CI = 1.76–31.87 and AOR = 8.25; 95% CI = 1.10–61.95 respectively).
Consumption of alcoholic beverages
The prevalence (Table 3) of adolescents with unplanned pregnancies who consumed alcoholic beverages was greater in those who resided in a non-intact family (51.6 vs. 32.7%), with smoking at home (43.1 vs. 40.6%), or who had friends who smoked (44.0 vs. 36.4%) compared with adolescents with planned pregnancies who resided in an intact family and who did not have smoking at home or friends who smoked.
Table 3.
Multivariate logistic regression analysis of factors that are associated with the consumption of alcoholic beverages among adolescents with unplanned and planned pregnancy
| Consumption of alcoholic beverages | ||||||
| Unplanned pregnancy (n = 467) |
Planned pregnancy (n = 318) |
|||||
| Yes/No | % | Adjusted OR (95% CI)a |
Yes/No | % | Adjusted OR (95% CI)a |
|
| Non-intact family | ||||||
| Yes | 81/76 | 51.6 | 1.79(1.17–2.74)* | 52/107 | 32.7 | 0.92(0.56–1.49) |
| No | 113/197 | 36.5 | 53/106 | 33.3 | ||
| Smoking at home | ||||||
| Yes | 98/170 | 36.6 | 0.80(0.53–1.21) | 55/85 | 39.3 | 1.64(1.01–2.66)* |
| No | 96/103 | 48.2 | 50/128 | 28.1 | ||
| Alcohol drinking at home | ||||||
| Yes | 156/206 | 43.1 | 1.47(0.91–2.39) | 78/114 | 40.6 | 2.31(1.36–3.91)* |
| No | 38/67 | 36.2 | 27/99 | 21.4 | ||
| Friends who smoke | ||||||
| Yes | 165/201 | 44.0 | 2.11(1.25–3.55)* | 86/150 | 36.4 | 2.01(1.11–3.65)* |
| No | 29/63 | 31.5 | 19/63 | 23.2 | ||
| Friends who consume alcoholic beverages | ||||||
| Yes | 192/231 | 45.4 | 17.35(4.14–72.65)* | 100/170 | 63.0 | 6.71(2.51–17.93)* |
| No | 2/42 | 4.5 | 5/43 | 10.4 | ||
Adjusted for the variables employed mother and the relationship between the adolescent and her mother. AOR = Adjusted Odds ratio; 95% CI = 95% Confidence interval.
P <0.05; p >0.05.
Results of the multivariate logistic regression analysis show that living in a non-intact family household (AOR = 1.79; 95% CI = 1.17–2.74) was associated with the consumption of alcohol in adolescents with unplanned pregnancies but not in those with planned pregnancies (AOR = 0.92; 95% CI = 0.56–1.49). On the other hand, having friends who smoked (AOR = 2.11; 95% CI = 1.25–3.55 vs. AOR = 2.01; 95% CI = 1.11–3.65), or having friends who consumed alcoholic beverages (AOR = 17.35; 95% CI = 4.14–72.65 vs. AOR = 6.71; 95% CI = 2.51–17.93) were associated with the consumption of alcoholic beverages in adolescents with unplanned and planned pregnancies.
Discussion
Our results show that living in a non-intact family household and the presence of friends who smoke and/or consume alcohol appear to be associated with smoking and consumption of alcoholic beverages among adolescents with unplanned pregnancies.
According to the analysis in this study, from the total sample, 25% of adolescents were pregnant. This prevalence of pregnant adolescents is higher than those reported in the United States of America (6%)10 and in South Africa (19.2%)12
Previous publications have shown that the rates of smoking and consumption of alcohol among adolescents with unplanned pregnancies are higher than those found in adolescents without it.2 The results of this study agree with those of these authors. We found that the percentage of smoking and alcohol use was higher in adolescents with unplanned pregnancies than in adolescents with planned pregnancies. Our results suggest that preventive smoking and alcoholic beverage consumption programs in general are not functioning adequately, and that these require review and reinforcement of their strategies in order to sensitize the population about the harm caused to health by smoking and alcohol use, acting mainly in groups of individuals who are vulnerable, such as female adolescents.
Living in a household with one, or no, biological parent has been associated with the development of risk habits and behaviors in adolescents.25,30,31 According to the analysis, adolescents with unplanned pregnancies who live in a non-intact family households have 1.7 times greater risk of smoking, and of consuming alcoholic beverages than those adolescents with planned pregnancies those reside with both biological parents. It is probable that this effect is due to a more tolerant attitude towards smoking by the permanent parent, or even to the unawareness and absence of parental in-home control concerning the adolescent's activities within as well as outside of the home.32,33
The results of some researchers show that socializing with friends who smoke and who consume alcoholic beverages constitutes an important risk factor for developing some health-risk behaviors, such as the use of illegal substances in adolescents.22 However, the relationship between socializing with friends who have some health-risk habits such as smoking and alcohol consumption with smoking and consumption of alcoholic beverages in adolescents with unplanned and planned pregnancies has not been previously documented. According to the analyses in this study, adolescents with unplanned pregnancies who socialize with friends who smake have 8.46-times greater risk of smoking and, if they socialize with friends who consume alcoholic beverages, the risk of smoking is 13.86 times greater compared with adolescents with planned pregnancies who have friends who smoke (AOR = 7.49) or who consume alcohol (AOR = 8.25).
On the other hand, the risk of an adolescent with unplanned pregnancy consuming beverages containing alcohol is 2.11 times if she socializes with friends who smoke and 17.35 times if her friends consume alcohol compared with the risk of alcohol use of adolescents with planned pregnancies who have friends who smoke (AOR = 2.01) or who consume alcohol (AOR = 6.71). It is possible that some of the following factors can favor this effect. Adolescence is a life stage during which changes take place in terms of organic and psychological development and adapting to society.
During this period of life, female adolescents are more willing to explore and experiment, they, on many occasions, do not consider that the decisions they make and the health-risk habits that they develop during this stage will exert an influence, whether positive or negative, on the rest of their lives. Additionally, during adolescence, young people are subjected to many pressures to acquire habits that are harmful to health. Even more, at this age, adolescents spend more time with their friends than with their families, and the opinion of friends in relation to the acquisition of certain risky habits and behaviors can be more influential than that of their parents.
Based on the results of this study, the presence of smoking or alcohol drinking at home does not favor the development of smoking or the consumption of alcohol in adolescents with unplanned pregnancies but it does in adolescents with planned pregnancies. However, it is noteworthy that prior investigations show that smoking and alcohol drinking at home favor the development of smoking and consuming alcohol in adolescents who are afflicted from some condition that compromises their health.34,35
According to some investigators, the association between smoking and alcohol consumption at home and the development of smoking and the consumption of alcoholic beverages in adolescents who have some condition that compromises their health is due to some of the following mechanisms. During adolescent development, the changes that present during this life stage can play a relevant role in the development of certain habits, such as smoking and alcohol use; these changes can present at younger ages and with greater frequency when they are based on direct experience, such as living with smoking parents or parents who consume alcohol.19,22,23 Smoking or alcohol drinking in the adolescents' home can be perceived by these young people as a sign that smoking or consuming alcoholic beverages is not harmful to health.34,35
Limitations and strengths
This study possesses the following methodological limitations that should be taken into consideration on generalizing its results: a) Detection of smoking and consumption of alcoholic beverages was performed through self-administered questionnaires: no objective tests to diagnose smoking or drinking, such as pulmonary function tests, carbon dioxide measurements, or blood alcohol level, were conducted. However, past investigations have shown that the use of self-reported questionnaires can be considered effective for measuring the diagnosis of smoking and drinking in epidemiological studies; b) On performing the statistical analysis, we found small cell counts in the logistic regression models, and d) this is a cross-sectional study; thus, no causal relationship can be established.
Conclusion
Living in an incomplete family household and the presence of friends with some health-risk behavior are associated with smoking and consumption of alcoholic beverages in adolescents with unplanned and planned pregnancies. It would appear that the same factors induce smoking and the consumption of alcohol in adolescents with unplanned and planned pregnancies.
On the other hand, pregnancy in adolescents (planned or not planned), is associated with other risk factors such as smoking and drinking.
It is important for adolescent health-care programs to be revised and for their strategies to be strengthened in order to reach the objectives for which they were created.
Funding
This work was supported by the Mixed Fund for the Promotion of Scientific and Technological Research, conacyt-Tamaulipas State Government (Grant code: TAMPS-2011-C35-176437).
Declaration of interests
The authors declare to have no conflict of interest directly or indirectly related to the manuscript contents.
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