A comparison of pregnancy and child health outcomes between teenage and adult mothers in the slums of Nairobi, Kenya

The study assessed and compared pregnancy and child health outcomes of teenage (aged less than 20 years) and adult (20-34 years of age) mothers. A total of 226 teenage and 205 adult mothers met the study criteria out of the 3,256 women in the reproductive age group (15-49 years) and 318 adolescent girls (12-14 years of age) covered by the Nairobi Cross-sectional Slums Survey (NCSS). The main comparison involved socio-demographic variables, events during pregnancy, obstetric outcome, child morbidity and mortality and care provided during an illness episode. Results showed that a significantly higher percentage of teenage mothers and their partners had lower educational achievement compared with adult mothers and their partners. They were more likely to be economically disadvantaged than the adult mothers. Teenage mothers and their parents were also less likely to have ever been married. The two groups of mothers were comparable in terms of the rate and timing of antenatal care visits, place of delivery, rate of operative deliveries, reported size of the baby at birth, child vaccination status and reported morbidity and health care practice during an illness episode. The index child was alive during the survey period for 89.4% of the teenage and 96.6% of the adult mothers (OR = 3.36; 95% CI = 1.34, 8.79; P = 0.004). Child survival rates in the two groups of mothers were found to be quite similar after controlled analysis for the influence of socio-economic factors. The study concluded that bad obstetric outcomes were not associated with maternal age. Although teenage and adult mothers were not significantly different on child health practices, children born to the former group died most frequently probably due to their poor socioeconomic achievements.     

The children of teenage mothers: patterns of early childbearing in two generations

Twenty years after a mostly black group of Baltimore women became adolescent mothers, the majority of their first-born children had not become adolescent parents, a finding that challenges the popular belief that the offspring of teenage mothers are themselves destined to become adolescent parents. Almost all of the offspring had had intercourse by age 19. About half of the young women had experienced a pregnancy before that age, and approximately one-third of the young men reported having impregnated a partner before age 19. The Baltimore youths were just as likely to have had a live birth before age 19 as were the children of teenage mothers in a national sample of urban blacks, and both of these groups were more likely to have done so than were the children of older mothers in the national sample. In the Baltimore sample, maternal welfare experience only increased a daughter's likelihood of early childbearing if welfare was received during her teenage years. Within the Baltimore sample, a direct comparison of the daughters who became adolescent mothers with their own mothers at a comparable age reveals that the daughters have bleaker educational and financial prospects than their mothers had, and are less likely to ever have married. These results suggest that today's teenage parents may be less likely than were previous cohorts of adolescent mothers to overcome the handicaps of early childbearing. This trend could portend the growth of an urban underclass, even though only a minority of the offspring of teenage mothers go on to become adolescent parents.     

Maternal age and cognitive and behavioural outcomes in middle childhood

Summary. The relationships between maternal age and childhood cognitive and behavioural outcomes were analysed in a birth cohort of New Zealand children studied until the age of 13 years. Increasing maternal age was associated with increasing scores on tests of cognitive ability and achievement and with decreasing reports of conduct problems. The correlations between maternal age and childhood cognitive/behavioural outcomes ranged from 0.11 to 0.21 with a median value of 0.18. These associations were adjusted statistically for the effects of maternal social background at the time of birth and for childhood history subsequent to birth. This analysis suggested that the poorer outcomes for children born to younger mothers reflected the cumulative effects of two sets of factors which placed these children at a disadvantage. Firstly, the offspring of younger mothers tended to be born into relatively poorly educated, socially disadvantaged families and secondly, these children were exposed to less nurturant and more changeable home environments. The net effects of differences in social background at birth and childrearing environments subsequent to birth were sufficient to explain most of the apparent correlation between maternal age and childhood cognitive/behavioural outcomes.     

Trends and correlates of single motherhood in Kenya: Results from the Demographic and Health Survey

Single motherhood exposes women to poorer socioeconomic and health outcomes, which may also negatively impact child outcomes. The Demographic and Health Surveys of 1989, 1993, 1998, 2003, and 2009 were used to investigate trends over time and factors associated with single motherhood in Kenya. Urban residence, older age, and poorer economic status were associated with single motherhood over time. Women with more than one child, and those with children under 15 years living at home were less likely to be single mothers. As women become single mothers at different stages, targeted and supportive strategies are required to mitigate associated risks.     

Association of maternal smoking and alcohol consumption with young adults' cannabis use: a prospective study

This 2006 study examined 1) whether maternal use of tobacco and consumption of alcohol when a child is 5 and 14 years of age predict cannabis use in young adults, and 2) whether this association is explained by possible confounding or mediating factors. Data were taken from a prospective birth cohort study of mothers and their children in Brisbane, Australia. This study was based on a cohort of 3,176 young adults who participated at the 21-year follow-up of the study and for whom data were available on maternal smoking and alcohol consumption 5 and 14 years after their birth. After controlling for possible confounders, the authors found that maternal smoking at 14 years was associated with frequent use of cannabis in offspring at 21 years, regardless of maternal smoking at 5 years. Children of mothers who drank more than one glass of alcohol at 5 years and continued at 14 years were more likely to use cannabis in early adulthood. The association between maternal substance use and offspring cannabis use was partially mediated by adolescent externalizing behavior and smoking measured at 14 years. Prevention programs that address maternal and adolescent tobacco use and adolescent externalizing behavior should be considered as strategies to reduce cannabis use by young adults.     

The health consequences of teenage fertility

A review of the literature on the health consequences of teenage pregnancy and childbirth shows remarkable similarity in findings from studies conducted in the United States, Canada, Britain, France and Sweden. In particular, results of studies conducted since 1970 have tended to indicate that the increased risk of maternal complications from pregnancy and delivery among teenagers--especially those older than 15--is associated more with socioeconomic factors than with the biological effects of age. Smaller differences in maternal mortality between teenagers and older women exist in England and Wales than in the United States and France; this finding suggests that England and Wales may have minimized the age or socioeconomic factors contributing to a difference in rates. Inadequate prenatal care may be a major cause of pregnancy-related complications for mothers, since teenagers in all countries are more likely than older mothers to seek care late in the pregnancy or not all. There is a very marked association between young age of mother and low birth weight in all countries. Sweden has the lowest rate of low birth weight at all maternal ages, and the United States generally has the highest. Some of the apparent effect of young maternal age on birth weight may be because the birth is likely to be the mother's first, and first births have a higher incidence of prematurity. As in the case of maternal health, inadequate prenatal care has been singled out as an important determinant of both prematurity and low birth weight. Late fetal death rates in the United States, England and Wales, and France are slightly higher among teenagers than among women in their 20s. In Canada and Sweden, however, no substantially increased risk for young women is found. Perinatal death rates, which one might expect to be influenced more by environmental factors than are late fetal deaths, show a more marked increase among infants of teenagers than do rates of late fetal deaths. Again, Sweden does not fit the pattern. Studies that separate data for young teens and older teenage mothers also indicate that increased perinatal and late fetal mortality rates may occur only among very young teenage mothers. There is no evidence of an overall increase in congenital malformations among babies born to teenagers. When individual birth defects are examined, some studies have shown increased rates of cardiovascular and central nervous system malformations among the children of teenage mothers.(ABSTRACT TRUNCATED AT 400 WORDS)     

The generational transmission of socioeconomic inequalities in child cognitive development and emotional health

Socioeconomic inequalities in the health of adults have been largely attributed to lifestyle inequalities. The cognitive development (CD) and emotional health (EH) of the child provides a basis for many of the health-related behaviours which are observed in adulthood. There has been relatively little attention paid to the way CD and EH are transmitted in the foetal and childhood periods, even though these provide a foundation for subsequent socioeconomic inequalities in adult health. The Mater-University of Queensland Study of Pregnancy (MUSP) is a large, prospective, pre-birth cohort study which enrolled 8556 pregnant women at their first clinic visit over the period 1981-1983. These mothers (and their children) have been followed up at intervals until 14 years after the birth. The socioeconomic status of the child was measured using maternal age, family income, and marital status and the grandfathers' occupational status. Measures of child CD and child EH were obtained at 5 and 14 years of age. Child smoking at 14 years of age was also determined. Family income was related to all measures of child CD and EH and smoking, independently of all other indicators of the socioeconomic status of the child. In addition, the grandfathers' occupational status was independently related to child CD (at 5 and 14 years of age). Children from socioeconomically disadvantaged families (previous generations' socioeconomic status as well as current socioeconomic status) begin their lives with a poorer platform of health and a reduced capacity to benefit from the economic and social advances experienced by the rest of society.     

Teen Motherhood and Long-Term Health Consequences

The objective of this article is to examine the association of teen motherhood and long-term physical and mental health outcomes. The physical and mental health components (PCS and MCS) of the SF-12 Healthy Survey in the NLSY79 health module were used to assess long-term health outcomes of women who experienced teenage motherhood. Various familial, demographic, and environmental characteristics were indentified and controlled for that may have predicted teen motherhood and long-term health outcomes. The two comparison groups for teen mothers were women who experienced teen-pregnancy only and women who were engaged in unprotected sexual activity as a teenage but did not experience pregnancy. Multivariate ordinary least squares regression was used for analysis. The average PCS and MCS for teen mothers was 49.91 and 50.89, respectively. Teen mothers exhibited poorer physical health later in life compared to all women as well as the comparison groups. When controlling for age, teen mothers had significantly lower PCS and MCS scores compared to all other women. Furthermore, when controlling for familial, demographic, and environmental characteristics, teen mothers exhibited significantly lower PCS and MCS scores. When comparing teen mothers to the two comparison groups, PCS was not statistically different although MCS was significantly lower in the teen-pregnancy group. Teen motherhood does lead to poorer physical health outcomes later in life. On the other hand, poorer mental health outcomes in later life may be attributed to the unmeasured factors leading to a teen pregnancy and not teen motherhood itself. Additional research needs to be conducted on the long-term consequences of teen motherhood.     

Young maternal age and infant mortality: the role of low birth weight

In 1980, there were 562,330 babies born in the United States to teenage mothers (19 years of age or younger). The offspring of teenage mothers have long been known to be at increased risk of infant mortality, largely because of their high prevalence of low birth weight (less than 2,500 grams). We used data from the National Infant Mortality Surveillance (NIMS) project to examine the effect of young maternal age and low birth weight on infant mortality among infants born in 1980 to U.S. residents. This analysis was restricted to single-delivery babies who were either black or white, who were born to mothers ages 10-29 years, and who were born in one of 48 States or the District of Columbia. Included were 2,527,813 births and 28,499 deaths (data from Maine and Texas were excluded for technical reasons). Direct standardization was used to calculate the relative risks, adjusted for birth weight, of neonatal mortality (less than 28 days of life) and postneonatal mortality (28 days to less than 1 year of life) by race and maternal age. There was a strong association between young maternal age and high infant mortality and between young maternal age and a high prevalence of low birth weight. Neonatal mortality declined steadily with increasing maternal age. After adjusting for birth weight, the race-specific relative risks for babies born to mothers less than 16 years of age were still elevated from 11 to 40 percent, compared with babies born to mothers 25-29 years of age.(ABSTRACT TRUNCATED AT 250 WORDS)     

Maternal smoking during pregnancy predicts nicotine disorder (dependence or withdrawal) in young adults – a birth cohort study

Objective: To investigate whether maternal smoking during pregnancy predicts offspring nicotine disorder (dependence or withdrawal) at 21 years.
Method: Participants comprised a prospective birth cohort involving 7,223 singleton children whose mothers were enrolled between 1981 and 1983 at the first antenatal visit to the Mater Mothers' Hospital, Brisbane, Queensland. The present sub-cohort consisted of 2,571 youth who completed the Composite International Diagnostic Interview-computerised version (CIDI-Auto) that assesses nicotine dependence and withdrawal according to DSM-IV diagnostic criteria at the 21-year follow-up.
Results: 12.8% of offspring met criteria for nicotine dependence and 8.5% met criteria for withdrawal. 16.6% met criteria for either dependence or withdrawal. Smoking during pregnancy resulted in offspring being more likely to have dependence or withdrawal at 21 years than offspring of mothers who never smoked (age adjusted odds ratio 1.53 (95% CI: 1.19-1.96).
Conclusions: Findings emphasise the long-term adverse effects of maternal smoking during pregnancy, including nicotine dependence in young adult offspring.
Implications: Public health approaches should strengthen arguments for mothers to cease smoking during pregnancy in view of the long-term health implications for offspring, and reinforce measures to help smokers among pregnant women and women of childbearing age to stop.     

Prenatal and Parenting Stress on Adolescent Maternal Adjustment: Identifying a High-Risk Subgroup

OBJECTIVES: Identifying adolescents who are at increased risk for a particularly difficult pregnancy and adjustment into parenthood is important, as the physical and psychological development of their infants rest in the well-being of these new mothers. This study aims to examine the effects of prenatal stress and parenting stress and the association with: (1) adolescent maternal adjustment; and (2) postpartum emotional distress. METHODS: In a prospective longitudinal cohort study, 154 pregnant adolescents (age 14-19) from 10 public clinics were interviewed four times from the third trimester of pregnancy to 16 months postpartum. Planned comparisons of four stress groups were used to compare mean scores for measures of feelings about motherhood, infant care, parenting competency, and emotional distress. RESULTS: Adolescent mothers who experienced high prenatal stress and high parenting stress had lower maternal adjustment (i.e., fewer positive feelings about motherhood, less infant care, and low parenting competency) and high postpartum emotional distress. Even when compared to adolescent mothers who experienced prenatal or parenting stress only, these adolescents were still at a greater disadvantage. CONCLUSIONS: Results suggest that adolescents who experience high stress during and after pregnancy are at increased risk for difficult maternal adjustment and high postpartum emotional distress. Findings support the need for health services targeting this subgroup of adolescent mothers, including both prenatal and parenting support. Early intervention to increase maternal adjustment and decrease emotional distress should remain a priority in facilitating the most optimal maternal and child health outcomes.     

Attachment interaction behavior between young teenage mothers and their infants

Behavioral interaction between teenage mothers and their infants was explored. Twenty-six (low income level) Hispanic teenage mothers (mean age 15 years) and their infants (mean age 13.5 months) were compared with an older control group of 30 mothers (mean age 26 years) and their infants (mean age 14.0 months). Infant attachment, exploration, and stress-adaptation behaviors and maternal ability to contact, encourage, and comfort the infant were evaluated. Twenty-six percent of the control infants showed limited ability to cope with stress compared to 47% of infants of teenage mothers. Control mothers differed significantly from teenage mothers in effective eye, verbal, physical contact, and smiling behaviors. These findings suggest that limited teenage maternal behaviors may potentially have a negative psychologic effect for both infants and their young mothers.     

Cigarette smoking from adolescence to young adulthood: women's developmental trajectories and associates outcomes.

OBJECTIVES: This study aimed to compare 1,442 women with distinct developmental trajectories of smoking from ages 13-23 on important young adult outcomes at age 29 (e.g., education, income, mental and physical health, arrest history, drug and alcohol abuse), as well as early transitions to sexual intercourse, parenthood, and marriage. METHODS: Women were classified as Abstainers or into 1 of 5 trajectory classes for which they had the highest probability of membership: Stable Highs, Early Increasers, Late Increasers, Triers, and Decreasers. Regression analysis was used to model outcomes as a function of trajectory class membership. RESULTS: Abstainers and Triers generally had more favorable outcomes than Stable Highs and Early Increasers. Decreasers were more likely to graduate from college than Stable Highs and Early Increasers and had a lower arrest rate than Stable Highs. Women who increased their smoking from initial low levels (Late Increasers) generally had poorer young adult outcomes compared to Triers and Abstainers, but lower risk for early sex and early parenthood compared to Stable Highs and Early Increasers. CONCLUSIONS: Women with certain patterns of smoking from age 13-23 are at heightened risk for early transitions to sexual activity and parenthood, as well as health, behavioral, and socioeconomic problems during young adulthood.     

Demographic Characteristics,Health Behaviors Before and During Pregnancy,and Pregnancy and Birth Outcomes in Mothers with Different Pregnancy Planning Status

Studies on pregnancy intentions and their consequences have yielded mixed results. Here, we comprehensively analyzed the maternal characteristics, health behaviors before and during pregnancy, as well as pregnancy and birth outcomes, across three different pregnancy planning status in 861 women participating in an ongoing Asian mother-offspring cohort study. At 26–28 weeks’ gestation, the women’s intention and enthusiasm toward their pregnancy were used to classify their pregnancy into planned or unplanned, and unplanned pregnancy was further subdivided into mistimed or unintended. Data on maternal characteristics, health behaviors, and pregnancy outcomes up to that stage were recorded. After delivery, birth outcomes of the offspring were recorded. Linear and logistic regression analyses were performed. Overall, 56 % had a planned pregnancy, 39 % mistimed, and 5 % unintended. Compared to women who planned their pregnancy, women with mistimed pregnancy had higher body mass index and were more likely to have cigarette smoke exposure and less likely to have folic acid supplementation. At 26–28 weeks’ gestation, unintended pregnancy was associated with increased anxiety. Neonates of mistimed pregnancy had shorter birth length compared to those of planned pregnancy, even after adjustment for maternal baseline demographics. These findings suggest that mothers who did not plan their pregnancy had less desirable characteristics or health behaviors before and during pregnancy and poorer pregnancy and birth outcomes. Shorter birth length in mistimed pregnancy may be attributed to maternal behaviors before or in the early stages of pregnancy, therefore highlighting the importance of preconception health promotion and screening for women of child-bearing age.     

Children's delayed development and behavior problems: impact on mothers' perceived physical health across early childhood

Mothers of children with developmental delays may experience poorer psychological well-being than other mothers; however, little research has examined how delayed development in children might predict mothers' perceived physical well-being. Children with delayed development manifest heightened behavior problems, which may negatively affect maternal well-being. We examined the associations between developmental delay and behavior problems at child age 3 and mothers' self-perceived physical health at child ages 3, 4, and 5, in families of 218 children with and without developmental delays. The study sample comprised 218 families from central Pennsylvania and Southern California, USA who were recruited through community agencies that provide diagnostic and intervention services for individuals with development difficulties. We found that mothers of children with delayed development at age 3 reported poorer concurrent and later physical health than mothers of children with typical development. Broadening the analyses to include not only child development status (delayed development versus typical development) but also child behavior problems at age 3, only child behavior problems and the interaction of development status and behavior problems, but not development status itself, predicted maternal health. Early child behavior problems contributed to later maternal health above and beyond early maternal health, suggesting a possible causal association between child behavior problems and mothers' physical health. The relation between child behavior problems and maternal health was moderated by mothers' parenting stress and mediated by depressive symptoms. Mothers of children with both delayed development and high behavior problems are a particular risk group that may be especially in need of early intervention. Further research should examine the behavioral and biological pathways by which these child-related stressors influence mothers' physical health.     

Effect of teenage pregnancy on educational disabilities in kindergarten

Teenage pregnancies have become a public health issue because of their observed negative effects on perinatal outcomes and long-term morbidity. The association of young maternal age and long-term morbidity is usually confounded, however, by the high prevalence of poverty, low level of education, and single marital status among teenage mothers. The authors assess the independent effect of teenage pregnancy on educational disabilities and educational problems in a total population of children who entered kindergarten in Florida in 1992--1994 and investigate how controlling for potentially confounding factors affects the relation between teenage pregnancies and poor outcome. When no other factors are taken into account, children of teenage mothers have significantly higher odds of placement in certain special education classes and significantly higher occurrence of milder education problems, but when maternal education, marital status, poverty level, and race are controlled, the detrimental effects disappear and even some protective effects are observed. Hence, the increased risk for educational problems and disabilities among children of teenage mothers is attributed not to the effect of young age but to the confounding influences of associated sociodemographic factors. In contrast to teen age, older maternal age has an adverse effect on a child's educational outcome regardless of whether other factors are controlled for or not.     

Disparities in exposure to air pollution during pregnancy

Previous research shows poorer birth outcomes for racial and ethnic minorities and for persons with low socioeconomic status (SES). We evaluated whether mothers in groups at higher risk for poor birth outcomes live in areas of higher air pollution and whether higher exposure to air pollution contributes to poor birth outcomes. An index representing long-term exposure to criteria air pollutants was matched with birth certificate data at the county level for the United States in 1998-1999. We used linear regression to estimate associations between the air pollution index and maternal race and educational attainment, a marker for SES of the mother, controlling for age, parity, marital status, and region of the country. Then we used logistic regression models both to estimate likelihood of living in counties with the highest levels of air pollution for different racial groups and by educational attainment, adjusting for other maternal risk factors, and to estimate the effect of living in counties with higher levels of air pollution on preterm delivery and births small for gestational age (SGA). Hispanic, African-American, and Asian/Pacific Islander mothers experienced higher mean levels of air pollution and were more than twice as likely to live in the most polluted counties compared with white mothers after controlling for maternal risk factors, region, and educational status [Hispanic mothers: adjusted odds ratio (AOR) = 4.66; 95% confidence interval (95% CI), 1.92-11.32; African-American mothers: AOR = 2.58; 95% CI, 1.00-6.62; Asian/Pacific Islander mothers: AOR = 2.82; 95% CI, 1.07-7.39]. Educational attainment was not associated with living in counties with highest levels of the air pollution index (AOR = 0.95; 95% CI, 0.40-2.26) after adjusting for maternal risk factors, region of the country, and race/ethnicity. There was a small increase in the odds of preterm delivery (AOR = 1.05; 95% CI, 0.99-1.12) but not SGA (AOR = 0.96; 95% CI, 0.86-1.07) in a county with high air pollution. Additional risk of residing in areas with poor air quality may exacerbate health problems of infants and children already at increased risk for poor health.     

Maternal education in relation to early and late child health outcomes: findings from a Brazilian cohort study.

In a population-based cohort of approximately 6000 Brazilian children, the associations between maternal education and a number of child health outcomes were studied while controlling for potentially confounding variables such as family income and education of the husband. In the crude analyses, maternal education was associated with perinatal and infant mortality, hospital admissions in the first 20 months of life and the three nutritional indicators (length-for-age, weight-for-age and weight-for-length) at mean age 20 months. After adjustment for confounding, the apparent associations with outcomes in early infancy--birthweight and perinatal mortality--were no longer present, while that with infant mortality persisted despite being reduced. Strong associations remained with later outcomes including hospital admissions, length-for-age and weight-for-age at mean age 20 months. Among infants born to women with little or no schooling, deaths due to diarrhoea, pneumonia and other infectious diseases were particularly common. These findings support the hypothesis that maternal education has an effect on child health which is partly independent from that of other socioeconomic factors; they also suggest that maternal care is more important than the biological characteristics of the mothers since stronger effects were observed for the late (postneonatal mortality, hospital admissions and nutritional status) than for the early (birthweight, perinatal mortality) outcomes.     

Epidemiologic evidence for the fetal overnutrition hypothesis: findings from the mater-university study of pregnancy and its outcomes

The fetal overnutrition hypothesis proposes that greater maternal adiposity results in increased obesity throughout life in the offspring. The authors examined the associations between parental prepregnancy body mass index (BMI; weight (kg)/height (m)(2)), based on height and weight reported by the mother at her first antenatal clinic visit, and offspring BMI (height and weight measured at age 14 years) in 3,340 parent-offspring trios from a birth cohort based in Brisbane, Australia (mothers were recruited in 1981-1984). The maternal-offspring BMI association was stronger than the paternal-offspring BMI association. In the fully adjusted model, the increase in standardized offspring BMI at age 14 for a one-standard-deviation (SD) increase in maternal BMI was 0.362 SD (95% confidence interval: 0.323, 0.402), and the corresponding result for a one-SD increase in paternal BMI was 0.239 SD (95% confidence interval: 0.197, 0.282). There was statistical support for a difference in the magnitude of the association between maternal-offspring BMI and paternal-offspring BMI in all confounder-adjusted models tested (all p's < 0.0001). In sensitivity analyses taking account of different plausible levels of nonpaternity (up to 15%), the greater maternal effect remained. These findings provide some support for the fetal overnutrition hypothesis.     

Does maternal smoking during pregnancy have a direct effect on future offspring obesity? Evidence from a prospective birth cohort study

The authors used a population-based birth cohort of 3,253 children (52% males) born in Brisbane, Australia, between 1981 and 1984 to prospectively examine whether maternal smoking during pregnancy was associated with offspring overweight and obesity. The authors compared mean body mass indexes (weight (kg)/height (m)2) and levels of overweight and obesity at age 14 years among offspring by patterns of maternal smoking (never smoked, smoked before and/or after pregnancy but not during pregnancy, or smoked during pregnancy). Adolescent body mass index and prevalences of overweight and obesity were greater in offspring whose mothers had smoked during pregnancy than in those whose mothers had never smoked. Body mass index and levels of overweight and obesity among adolescent offspring whose mothers stopped smoking during pregnancy but smoked at other times in the child's life were similar to those among offspring whose mothers had never smoked. These results were independent of a range of potentially confounding factors and suggest a direct effect of maternal smoking during pregnancy on adolescent overweight and obesity. They provide yet another incentive for pregnant women to be persuaded not to smoke and for young women to be encouraged to never take up smoking.