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Inadequate prenatal care and risk of preterm delivery among adolescents: a retrospective study over 10 years

      Objective

      The aim of this study was to determine whether inadequate prenatal care is associated with increased risk of preterm birth among adolescents.

      Study Design

      We selected a random sample of women under age 20 years with singleton pregnancies delivering in Washington State between 1995 and 2006. Multivariate logistic regression was used to assess the association between prenatal care adequacy (percent of expected visits attended, adjusted for gestational age) and preterm birth.

      Results

      Of 30,000 subjects, 27,107 (90%) had complete data. Women without prenatal care had more than 7-fold higher risk of preterm birth (n = 84 [24.1%]; adjusted odds ratio [aOR], 7.4), compared with those attending 75-100% of recommended visits (n = 346 [3.9%]). Women with less than 25%, 25-49%, or 50-74% of expected prenatal visits were at significantly increased risk of preterm birth; risk decreased linearly as prenatal care increased (n = 60 [9.5%], 132 (5.9%], 288 [5%]; and aOR, 2.5, 1.5, and 1.3, respectively).

      Conclusion

      Inadequate prenatal care is strongly associated with preterm birth among adolescents.

      Key words

      The US teenage pregnancy rate is one of the highest among industrialized nations.
      • Jones E.F.
      Alan Guttmacher Institute
      Teenage pregnancy in industrialized countries: a study.
      Although the rate of teen pregnancy declined between its peak of 61.8 births per 1000 teens aged 15-19 years in 1991 and reached a low of 40.5 in 2005, preliminary data for 2006-2007 show that over those 2 years, rates have risen to 42.5 births per 1000 girls aged 15-19 years.
      • Hamilton B.E.
      • Martin J.A.
      • Ventura S.J.
      Births: preliminary data for 2007.
      For Editors' Commentary, see Table of Contents
      Data suggest that pregnant teenagers are more likely than adult women to suffer adverse medical and obstetric outcomes, such as hypertensive disease, anemia, infection, and depression, during pregnancy and may continue to have consequences, like depression later in life, delayed or discontinued education, or increased utilization of public assistance.
      • Jones E.F.
      Alan Guttmacher Institute
      Teenage pregnancy in industrialized countries: a study.
      • Cunnington A.J.
      What's so bad about teenage pregnancy?.
      • Koniak-Griffin D.
      • Turner-Pluta C.
      Health risks and psychosocial outcomes of early childbearing: a review of the literature.
      • Gilbert W.
      • Jandial D.
      • Field N.
      • Bigelow P.
      • Danielsen B.
      Birth outcomes in teenage pregnancies.
      • Kalil A.
      • Kunz J.
      Teenage childbearing, marital status, and depressive symptoms in later life.
      Age younger than 17 years is associated with a 1.5-1.9 times increased risk of preterm birth.
      American College of Obstetricians and Gynecologists
      Assessment of risk factors for preterm birth Clinical management guidelines for obstetrician-gynecologists.
      Preterm birth, defined as delivery before 37 weeks' gestational age, affects more than 10% of live births annually in the United States and is responsible for three-quarters of all neonatal mortality and 35% of all health care spending for infants in the United States.
      American College of Obstetricians and Gynecologists
      Assessment of risk factors for preterm birth Clinical management guidelines for obstetrician-gynecologists.
      American College of Obstetricians and Gynecologists
      Management of preterm labor ACOG practice bulletin no. 43, May 2003.
      Prenatal care may decrease adverse pregnancy outcomes for teenage pregnant women by reducing risk factors through education and social support.
      • Raatikainen K.
      • Heiskanen N.
      • Verkasalo P.
      • Heinonen S.
      Good outcome of teenage pregnancies in high-quality maternity care.
      • Quinlivan J.A.
      • Evans S.F.
      Teenage antenatal clinics may reduce the rate of preterm birth: a prospective study.
      Teenage and adult mothers probably differ in their access to and utilization of prenatal care.
      • Hamilton B.E.
      • Martin J.A.
      • Ventura S.J.
      Births: preliminary data for 2007.
      We hypothesize that inadequate prenatal care will increase the risk of preterm birth for adolescents.

      Materials and Methods

      We used Washington State birth record data to conduct a population-based cohort study of women who delivered between the years 1995 and 2006. Eligible subjects were women under 20 years of age who had singleton births during the study period. From this population, 30,000 women were selected at random for inclusion. Women with pregnancies affected by fetal malformations or chromosomal abnormalities were excluded, as were women with recorded gestational age at delivery greater than 43 weeks. The primary outcome was delivery at less than 37 weeks. The primary exposure of interest was adequacy of prenatal visits. The study received approval from the University of Washington Institutional Review Board.
      Preterm birth was defined as gestational age less than 37 weeks at the time of delivery. To classify adequacy of prenatal care, we calculated a ratio of the actual number of prenatal visits compared with the expected number of visits for a delivery at a given gestational age. We used the American College of Obstetrics and Gynecology guidelines for the schedule of prenatal care visits to calculate the expected number of visits: every 4 weeks from the first prenatal visit through 28 weeks, every 2-3 weeks from 28 weeks until 36 weeks, and weekly thereafter.
      American Academy of Pediatrics, American College of Obstetricians and Gynecologists
      Antepartum care.
      We created a ratio of observed to expected visits, similar to Kotelchuck's prenatal care index (APNCU-Adequacy of Prenatal Care Utilization Index).
      • Kotelchuck M.
      An evaluation of the Kessner Adequacy of Prenatal Care Index and a proposed Adequacy of Prenatal Care Utilization Index.
      For the purposes of analysis, we divided adequacy of prenatal care into 6 categories: no prenatal care, less than 25%, 25-49%, 50-74%, 75-100%, and greater than 100% of expected. We used an observed to expected visit ratio of 75-100% of prenatal visits as our referent or ideal category. Other data included maternal age, race, insurance, smoking, first-trimester bleeding, prior preterm birth, pregestational diabetes, hypertensive disease, and culture-positive Neisseria gonorrhea or Chlamydia trachomatis. Data for N gonorrhea and C trachomatis were available only after 2002.
      All analyses were conducted using Stata 10.0 (Stata Corp, College Station, TX). One-way ANOVA and χ2 tests were used to test for differences in demographic, reproductive, and behavioral variables across the 6 exposure categories of prenatal care adequacy. Univariate logistic regression was used to assess the crude association between prenatal care and preterm birth.
      In the multivariate analysis, variables that were potential confounders based on the univariate analysis or were strongly associated with preterm birth in the literature were included in all models (maternal age, race/ethnicity, marital status, maternal smoking, and prior preterm birth); subjects missing data for any of these variables were excluded from all analyses.
      A subgroup analysis by teen age groups (maternal age ≤15 years, 16-17 years, and 18-19 years) was conducted, as was a multinomial logistic model with 3 categories of birth outcome (<32 weeks, 32-36 weeks, 37+ weeks). We conducted a stratified analysis in 3 year blocks to assess change in risk during the study period.
      To detect a 30% difference in the rate of preterm birth for teens with poor prenatal care (80% power and significance level of alpha = 0.05), we required a sample size of 15,000. There are approximately 8000 live births to teens annually in Washington State. Assuming that 20% of all births in Washington State would have the variables of interest recorded completely, it was presumed that there would be data on 1600 teen births annually. Therefore, we determined that we needed to review approximately 10 years of data to detect a 30% difference in the rate of preterm birth for teens with poor prenatal care.

      Results

      Of the random selection of 30,000 women under age 20 years with singleton births in Washington State from 1995 to 2006, 27,107 (90%) had complete data and were included in this analysis. We excluded 642 subjects (2%) because their pregnancies were affected by fetal malformations (n = 634) or their recorded gestational age at delivery was greater than 43 weeks (n = 8). An additional 2251 subjects (8%) were excluded for missing maternal race, marital status, maternal smoking, and prior preterm birth or parity variables.
      The overall rate of preterm birth in this population was 7% (Table 1). A total of 349 women received no prenatal care, whereas 8983 attended 75-100% of expected visits. For teens with no prenatal care, 24.1% of births were preterm, compared with 3.9% preterm births with 75-100% of visits and 10.5% preterm births for more than 100% of visits. Eighty-eight percent of preterm births occurred between 32 and 36 weeks' gestational age.
      TABLE 1Gestational age at delivery by visit category
      VariablePercentage of observed/expected prenatal visits
      None, n (%)<24%, n (%)25-49%, n (%)50-74%, n (%)75-100%, n (%)>100%, n (%)Total, n (%)
      Total births349 (1.3)629 (2.3)2254 (8.3)5718 (21.1)8983 (33.1)9174 (33.8)27,107
      >37 weeks265 (75.9)569 (90.5)2122 (94.1)5430 (95.0)8637 (96.1)8214 (89.5)25,237 (93.1)
      <37 weeks84 (24.1)60 (9.5)132 (5.9)288 (5.0)346 (3.9)960 (10.5)1870 (6.9)
      32-36 weeks62 (17.8)54 (8.6)119 (5.3)252 (4.4)320 (3.6)841 (9.2)1648 (6.1)
      <32 weeks22 (6.3)6 (0.9)13 (0.6)36 (0.6)26 (0.3)119 (1.3)222 (0.8)
      Debiec. Inadequate prenatal care and risk of preterm delivery in adolescents. Am J Obstet Gynecol 2010.
      Women with inadequate prenatal care were younger and more likely to be unmarried, nulliparous, have government or charity-funded insurance, smoke during pregnancy, and have a history of preterm birth (Table 2). Women with first-trimester bleeding, pregestational diabetes, and preeclampsia were more likely to have attended more than 100% of anticipated prenatal care visits. Rates of chronic hypertension were similar between groups. There was no significant difference in N gonorrhea or C trachomatis prevalence by prenatal care visit category for years with available data.
      TABLE 2Demographics of study population
      Valid (n = 27,107) unless otherwise stated;
      CharacteristicPercentage of observed/expected prenatal visits
      None (n = 349)<25% (n = 629)25-49% (n = 2254)50-74% (n = 5718)75-100% (n = 8983)>100% (n = 9174)P value
      Tests: 1-way analysis of variance for continuous variables, χ2 for categorical variables;
      Age, y17.5 ± 1.417.6 ± 1.417.7 ± 1.417.8 ± 1.317.9 ± 1.217.9 ± 1.2< .001
      Single313 (90)514 (82)1784 (79)4372 (77)6857 (76)6870 (75)< .001
      Nulliparous272 (94)427 (92)1710 (95)4580 (97)7599 (98)7811 (98)< .001
      Race
       White202 (58)293 (47)1219 (54)3458 (61)6125 (68)6558 (72)< .001
       Black31 (9)53 (8)170 (8)390 (7)449 (5)465 (5)
       Other116 (33)283 (45)865 (38)1870 (33)2409 (27)2151 (23)
      Uninsured
      n = 18,424;
      121 (62)331 (80)1086 (76)2669 (71)4132 (67)4092 (63)< .001
      Smoking94 (27)147 (23)486 (22)1223 (21)2023 (23)2150 (23).017
      Chronic hypertension1 (<1)010 (<1)18 (<1)26 (<1)43 (<1).197
      Preeclampsia18 (5)15 (2)112 (5)305 (5)546 (6)742 (8)< .001
      First-trimester bleeding5 (1)3 (0.5)19 (0.8)51 (0.9)82 (0.9)128 (1.4).005
      Diabetes2 (<1)5 (1)27 (1)57 (1)100 (1)165 (2)< .001
      C trachomatis
      n = 8222;
      6 (4)10 (5)41 (5)79 (4)114 (4)113 (4).924
      N gonorrhea
      n = 8222;
      1 (<1)04 (<1)4 (<1)4 (<1)8 (<1).386
      Prior preterm birth
      Among parous women only.
      3 (1)3 (0.5)8 (0.4)31 (0.5)32 (0.4)46 (0.5)< .001
      Debiec. Inadequate prenatal care and risk of preterm delivery in adolescents. Am J Obstet Gynecol 2010.
      a Valid (n = 27,107) unless otherwise stated;
      b Tests: 1-way analysis of variance for continuous variables, χ2 for categorical variables;
      c n = 18,424;
      d n = 8222;
      e Among parous women only.
      In the univariate analysis, women who had no prenatal care were at nearly 8-fold higher risk of preterm birth (odds ratio [OR], 7.9; 95% confidence interval [CI], 6.1–10.3), compared with those who attended 75-100% of the recommended visits (Table 3). Women who had less than 25%, 25-49%, or 50-74% of the recommended prenatal care visits were also at significantly increased risk of preterm birth, and risk appeared to decrease linearly as prenatal care increased. Women who had more than 100% of the recommended prenatal care were also at higher risk of preterm birth (OR, 2.9; 95% CI, 2.6–3.3).
      TABLE 3Odds of preterm birth
      VariableOR (95% CI)
      Univariate analysis;
      aOR (95% CI)
      aOR: adjusted for maternal age, ethnicity, marital status, smoking, and prior preterm birth.
      (n = 27,107)
      No prenatal care7.9 (6.1–10.3)7.4 (5.7–9.7)
      <25%2.6 (2.0–3.5)2.5 (1.9–3.3)
      25–49%1.6 (1.3–1.9)1.5 (1.2–1.8)
      50–74%1.3 (1.1–1.5)1.3 (1.1–1.5)
      75–100%ReferentReferent
      >100%2.9 (2.6–3.3)2.9 (2.6–3.3)
      Maternal age0.94 (0.91–0.97)
      Marital status1.09 (0.97–1.2)
      Rural0.93 (0.83–1.04)
      Black race1.3 (1.1–1.6)
      Prior preterm birth1.5 (1.1–2.0)
      Use of public funds0.8 (0.7–0.9)
      Smoked1.0 (0.9–1.2)
      First-trimester bleeding2.5 (1.8–3.5)
      aOR, adjusted odds ratio; CI, confidence interval.
      Debiec. Inadequate prenatal care and risk of preterm delivery in adolescents. Am J Obstet Gynecol 2010.
      a Univariate analysis;
      b aOR: adjusted for maternal age, ethnicity, marital status, smoking, and prior preterm birth.
      In the univariate analysis, there was an increased odds of preterm birth associated with black race (1.3; 95% CI, 1.1–1.6), prior preterm birth (1.5; 95% CI, 1.1–2.0), and first-trimester bleeding (2.5; 95% CI, 1.8–3.5). Increasing maternal age (0.94; 95% CI, 0.91–0.97) and use of public funds (0.8; 95% CI, 0.7–0.9) were associated with decreased risk of preterm birth.
      For the multivariate analysis, the model was adjusted for factors determined a priori (maternal age, ethnicity, smoking, prior preterm birth) or those determined to be significant in the univariate analysis (marital status). When adjusted for potential confounders, results were similar; all categories of inadequate and more than adequate prenatal care were associated with statistically significant increased risk of preterm birth (Table 3).
      In addition to the analyses presented here, multivariate analyses stratified by year of delivery (1995-1997, 1998-2000, 2001-2003, 2004-2006) or type of insurance (Medicaid, health maintenance organization, commercial insurance) as well as multivariate analyses adjusting for pregestational diabetes and preeclampsia yielded similar results (data not shown). Variables for which there was a significant amount of missing data (such as the use of public funds and first-trimester bleeding) were excluded from the final multivariate analysis because they significantly decreased power, but when the model was run with those variables included, there were no significant differences (data not shown).
      Adequacy of prenatal care was assessed by looking at total prenatal visits, rather than the date of prenatal care initiation. Although a delayed initial prenatal visit was also associated with increased risk of preterm birth, the total number of visits continued to predict the risk of preterm birth when stratified by the timing of the first visit (data not shown).
      Multivariate regression analyses stratified by maternal age produced similar results (Table 4). For all teenagers, women with no prenatal care were at highest risk of preterm birth when compared with subjects who attended 75-100% of expected visits. Attendance at greater than 100% of expected visits was also associated with significantly increased odds of preterm birth. For teens aged 16-19 years, women who had less than 25%, 25-49%, or 50-74% of the recommended prenatal care visits were at significantly increased risk of preterm birth. Results were qualitatively similar for teens aged 15 years or less but did not reach statistical significance, likely because of the small numbers of deliveries in this group.
      TABLE 4Odds of preterm birth by age
      Adjusted odds ratio: adjusted for maternal age, ethnicity, marital status, smoking, and prior preterm birth.
      VariableAge ≤15 y (n = 1584)16-17 (n = 7349)18-19 (n = 18,173)
      No prenatal care3.5 (1.4-9.0)8.1 (5.1-12.8)7.9 (5.5-11.3)
      <25%2.3 (0.93-5.5)2.5 (1.5-4.2)2.5 (1.7-3.6)
      25-49%1.1 (0.54-2.2)1.8 (1.2-2.5)1.4 (1.1-1.9)
      50-74%1.1 (0.65-2.0)1.4 (1.1-1.9)1.2 (1.0-1.5)
      75-100%ReferentReferentReferent
      >100%2.3 (1.4-3.8)2.7 (2.1-3.4)3.1 (2.7-3.7)
      Debiec. Inadequate prenatal care and risk of preterm delivery in adolescents. Am J Obstet Gynecol 2010.
      a Adjusted odds ratio: adjusted for maternal age, ethnicity, marital status, smoking, and prior preterm birth.
      In the multinomial logistic regression analysis, ORs were generally larger for associations with very preterm birth (<32 weeks) compared with moderately preterm birth (32-36 weeks) (Table 5). Specifically, women with no prenatal care had more than 25 times the risk for very preterm birth (adjusted OR [aOR], 25.5; 95% CI, 14.2–45.7), whereas they were at 6 times the risk of moderately preterm birth (aOR, 5.9; 95% CI, 4.4–8.0).
      TABLE 5Multinomial regression of preterm delivery
      Adjusted odds ratio: adjusted for maternal age, ethnicity, marital status, smoking, and prior preterm birth.
      Variable<32 wks32-36 wks
      No prenatal care25.5 (14.2-45.7)5.9 (4.4-8.0)
      <25%3.4 (1.4-8.3)2.4 (1.8-3.2)
      25-49%2.0 (1.0-3.9)1.4 (1.2-1.8)
      50-74%2.1 (1.3-3.6)1.2 (1.0-1.4)
      75-100%ReferentReferent
      >100%4.9 (3.2-7.4)2.8 (2.4-3.2)
      Debiec. Inadequate prenatal care and risk of preterm delivery in adolescents. Am J Obstet Gynecol 2010.
      a Adjusted odds ratio: adjusted for maternal age, ethnicity, marital status, smoking, and prior preterm birth.

      Comment

      This study sought to examine the relationship between prenatal care and preterm birth in adolescents. Our findings come from a random sample of more than 30,000 women under age 20 years who delivered in Washington State between 1995 and 2006. A major result of this study is that adolescents who received no prenatal care or attended less than 75% of expected visits were at much higher risk of preterm birth than those with optimal prenatal care utilization.
      This finding is robust, persisting even after controlling for recognized risk factors for preterm birth. Our results are consistent with prior studies of prenatal care for adolescents, which show that prenatal care programs that provide comprehensive medical and psychosocial services could improve maternal health and birth outcomes, including rates of preterm birth.
      • Quinlivan J.A.
      • Evans S.F.
      Teenage antenatal clinics may reduce the rate of preterm birth: a prospective study.
      • Elam-Evans L.
      • Adams M.
      • Gargiullo P.
      • Kiely J.
      • Marks J.
      Trends in the percentage of women who received no prenatal care in the United States, 1980-1992: contributions of the demographic and risk effects.
      • Scholl T.O.
      • Hediger M.L.
      • Belsky D.H.
      Prenatal care and maternal health during adolescent pregnancy: a review and meta-analysis.
      • Barnet B.
      • Duggan A.K.
      • Devoe M.
      Reduced low birth weight for teenagers receiving prenatal care at a school-based health center: effect of access and comprehensive care.
      The conclusions of this study must be interpreted in light of limitations in the dataset and study design. It is possible that factors other than the amount or quality of prenatal care are responsible for the preterm births in this study. For example, this study cannot adequately control for such factors as infectious exposure, socioeconomic status, and drug use, which may differ between the groups.
      This study is a retrospective study utilizing an established database. The accuracy of birth data is dependent on several sources including patient records, prenatal care documentation, and patient recall, some of which may not be accurate. Accrual of birth certificate data is a complex and variable process. Although the Washington State birth database does perform checks for reasonable range of visits and gestational ages, it does not specifically compare gestational age at delivery or number of prenatal visits with hospital or prenatal records.
      In addition, the dataset, although comprehensive, has only limited information on some variables. For example, the cause of preterm birth is not clearly identifiable from this set of data. The causal pathways for preterm birth caused by premature rupture of membranes versus spontaneous labor could be different and might affect the interpretation of the results. Certain variables that may be associated with preterm birth, such as exposure to N gonorrhea and C trachomatis have been recorded only since 2002, precluding analysis of the relationship between sexually transmitted infection and preterm birth in this study. Other variables such as insurance status and other socioeconomic information are inconsistently reported and thus were not included for final analysis.
      Whereas we did observe that almost one-quarter of all teens without prenatal care had a preterm birth, the overall rate of preterm birth in this study population was lower than expected (7%). This is somewhat surprising, given that the rate of preterm birth in the United States is more than 10% and that teen pregnancy is thought to be associated with increased preterm birth.
      American College of Obstetricians and Gynecologists
      Assessment of risk factors for preterm birth Clinical management guidelines for obstetrician-gynecologists.
      Although the Pacific Northwest in general, and Washington State in particular, has one of the lowest rates of preterm birth in the nation, there may be other factors contributing to the low rate of preterm birth observed here.

      Hamilton BE, Martin JA, Ventura SJ. Births: preliminary data for 2007. National vital statistics reports, Web release; vol 57, no. 12. Hyattsville, MD: National Center for Health Statistics. Released March 18, 2009.

      The low overall rate of preterm birth in this study may be accounted for by features of the study population. For instance, black race is a known risk factor for preterm birth, as is prior preterm birth.
      American College of Obstetricians and Gynecologists
      Assessment of risk factors for preterm birth Clinical management guidelines for obstetrician-gynecologists.
      In this sample, a mere 6% of subjects were black and less than 1% of our subject had a prior preterm birth. In addition, there are two estimates of gestational age in the Washington State birth record data: the recorded gestation estimate recorded at delivery and the gestational age calculated from the last menstrual period.
      The gestation estimate tends to demonstrate a lower percentage of preterm delivery than the calculated age. A priori, we opted to use the most conservative estimate, given that many teens have poor recollection of their last menstrual period. This likely contributed to the low rate of preterm birth seen in our study.
      Another notable finding of this study was that although the majority of preterm births occurred at 32-36 weeks, inadequate prenatal care was more strongly associated with very preterm birth (<32 weeks) than moderately preterm birth (32-36 weeks). This could suggest that there may be different causal pathways for preterm birth among adolescents underutilizing prenatal care or that prenatal care helps to prevent early preterm births. Alternatively, it could be a manifestation of late initiation of prenatal care. The financial impact and long-term health complications of infants born very preterm provide a significant impetus to discover interventions to reduce deliveries prior to 32 weeks.
      An unexpected finding of this study is that women with greater than 100% of expected visits were at an increased risk of preterm birth compared with those attending 75-100% of visits. A possible explanation of this result is that women who attend more than expected prenatal care visits may have had maternal or fetal conditions like diabetes or chronic hypertension that required closer surveillance than uncomplicated pregnancies, and such conditions could be independent risk factors for preterm birth.
      The study design precludes definitive clarification of this finding, but this explanation is consistent with prior work by Kogan et al,
      • Kogan M.D.
      • Martin J.A.
      • Alexander G.R.
      • Kotelchuck M.
      • Ventura S.J.
      • Frigoletto F.D.
      The changing pattern of prenatal care utilization in the United States, 1981-1995, using different prenatal care indices.
      which showed that intensive utilization of prenatal care was associated with such factors as multiple birth and that rates of preterm birth did not improve in the period during which increased prenatal care utilization was observed.
      There may be several reasons for adolescents to have delayed or inadequate access to prenatal care, including fear of familial repercussions, depression, coexistence of other risk-taking behaviors, or inadequate access to medical care. Hueston et al
      • Hueston W.J.
      • Geesey M.E.
      • Diaz V.
      Prenatal care initiation among pregnant teens in the United States: an analysis over 25 years.
      have shown that lack of health care coverage may be a significant impediment to early prenatal care. In other studies, expanded access to publicly funded prenatal care was associated with a reduction in inadequate use of prenatal care.
      • Hessol N.A.
      • Vittinghoff E.
      • Fuentes-Afflick E.
      Reduced risk of inadequate prenatal care in the era after Medicaid expansions in California.
      Possible etiologies for preterm labor and delivery include infectious and psychosocial factors.
      • Hitti J.
      • Nugent R.
      • Boutain D.
      • Gardella C.
      • Hillier S.L.
      • Eschenbach D.A.
      Racial disparity in risk of preterm birth associated with lower genital tract infection.
      • French J.I.
      • McGregor J.A.
      • Draper D.
      • Parker R.
      • McFee J.
      Gestational bleeding, bacterial vaginosis, and common reproductive tract infections: risk for preterm birth and benefit of treatment.
      • Covington D.
      • Justason B.
      • Wright L.
      Severity, manifestations, and consequences of violence among pregnant adolescents.
      Prenatal care may allow for treatment of symptomatic or unrecognized lower genital tract infections; modification of lifestyle habits such as smoking, diet, drug and alcohol use; and an opportunity for intervention in violent or socially isolating situations.
      Attentive prenatal care for young mothers may have transformative effects on individual women and offers a unique opportunity to prevent future unwanted pregnancies, access social services, and attend educational programs.
      • Fessler K.B.
      Social outcomes of early childbearing: important considerations for the provision of clinical care.
      Whereas the present study was not designed to assess etiologies of preterm birth or reasons for inadequate prenatal care utilization among adolescents, it demonstrates the importance of prenatal care for improving perinatal outcomes and the need for continued advocacy to diminish barriers to adolescents seeking health care. Our results suggest that efforts should be made to attract pregnant teenagers to prenatal care at an early gestational age and encourage attendance at prenatal visits. Further research should be done to determine impediments to prenatal care access, initiation, and attendance.

      Acknowledgments

      We thank the Washington State Department of Health for data access and acknowledge Dr Patricia Starzyk for her guidance and Mr Bill O'Brien for data management and programming assistance.

      References

        • Jones E.F.
        • Alan Guttmacher Institute
        Teenage pregnancy in industrialized countries: a study.
        Yale University Press, New Haven1986
        • Hamilton B.E.
        • Martin J.A.
        • Ventura S.J.
        Births: preliminary data for 2007.
        Natl Vital Stat Rep. 2009; 57
        • Cunnington A.J.
        What's so bad about teenage pregnancy?.
        J Fam Plann Reprod Health Care. 2001; 27: 36-41
        • Koniak-Griffin D.
        • Turner-Pluta C.
        Health risks and psychosocial outcomes of early childbearing: a review of the literature.
        J Perinat Neonatal Nurs. 2001; 15: 1-17
        • Gilbert W.
        • Jandial D.
        • Field N.
        • Bigelow P.
        • Danielsen B.
        Birth outcomes in teenage pregnancies.
        J Matern Fetal Neonatal Med. 2004; 16: 265-270
        • Kalil A.
        • Kunz J.
        Teenage childbearing, marital status, and depressive symptoms in later life.
        Child Dev. 2002; 73: 1748-1760
        • American College of Obstetricians and Gynecologists
        Assessment of risk factors for preterm birth.
        Obstet Gynecol. 2001; 98 (ACOG practice bulletin no. 31, October 2001 (replaces technical bulletin no. 206, June 1995; committee opinion no. 172, May 1996; committee opinion no. 187, September 1997; committee opinion no. 198, February 1998; and committee opinion no. 251, January 2001)): 709-716
        • American College of Obstetricians and Gynecologists
        Management of preterm labor.
        Int J Gynaecol Obstet. 2003; 82: 127-135
        • Raatikainen K.
        • Heiskanen N.
        • Verkasalo P.
        • Heinonen S.
        Good outcome of teenage pregnancies in high-quality maternity care.
        Eur J Public Health. 2006; 16: 157-161
        • Quinlivan J.A.
        • Evans S.F.
        Teenage antenatal clinics may reduce the rate of preterm birth: a prospective study.
        BJOG. 2004; 111: 571-578
        • American Academy of Pediatrics, American College of Obstetricians and Gynecologists
        Antepartum care.
        in: Guidelines for perinatal care. 6th ed. AAP, Elk Grove Village, IL2007: 83-137 (Washington, DC: ACOG)
        • Kotelchuck M.
        An evaluation of the Kessner Adequacy of Prenatal Care Index and a proposed Adequacy of Prenatal Care Utilization Index.
        Am J Public Health. 1994; 84: 1414-1420
        • Elam-Evans L.
        • Adams M.
        • Gargiullo P.
        • Kiely J.
        • Marks J.
        Trends in the percentage of women who received no prenatal care in the United States, 1980-1992: contributions of the demographic and risk effects.
        Obstet Gynecol. 1996; 87: 575-580
        • Scholl T.O.
        • Hediger M.L.
        • Belsky D.H.
        Prenatal care and maternal health during adolescent pregnancy: a review and meta-analysis.
        J Adolesc Health. 1994; 15: 444-456
        • Barnet B.
        • Duggan A.K.
        • Devoe M.
        Reduced low birth weight for teenagers receiving prenatal care at a school-based health center: effect of access and comprehensive care.
        J Adolesc Health. 2003; 33: 349-358
      1. Hamilton BE, Martin JA, Ventura SJ. Births: preliminary data for 2007. National vital statistics reports, Web release; vol 57, no. 12. Hyattsville, MD: National Center for Health Statistics. Released March 18, 2009.

        • Kogan M.D.
        • Martin J.A.
        • Alexander G.R.
        • Kotelchuck M.
        • Ventura S.J.
        • Frigoletto F.D.
        The changing pattern of prenatal care utilization in the United States, 1981-1995, using different prenatal care indices.
        JAMA. 1998; 279: 1623-1628
        • Hueston W.J.
        • Geesey M.E.
        • Diaz V.
        Prenatal care initiation among pregnant teens in the United States: an analysis over 25 years.
        J Adolesc Health. 2008; 42: 243-248
        • Hessol N.A.
        • Vittinghoff E.
        • Fuentes-Afflick E.
        Reduced risk of inadequate prenatal care in the era after Medicaid expansions in California.
        Med Care. 2004; 42: 416-422
        • Hitti J.
        • Nugent R.
        • Boutain D.
        • Gardella C.
        • Hillier S.L.
        • Eschenbach D.A.
        Racial disparity in risk of preterm birth associated with lower genital tract infection.
        Paediatr Perinat Epidemiol. 2007; 21: 330-337
        • French J.I.
        • McGregor J.A.
        • Draper D.
        • Parker R.
        • McFee J.
        Gestational bleeding, bacterial vaginosis, and common reproductive tract infections: risk for preterm birth and benefit of treatment.
        Obstet Gynecol. 1999; 93: 715-724
        • Covington D.
        • Justason B.
        • Wright L.
        Severity, manifestations, and consequences of violence among pregnant adolescents.
        J Adolesc Health. 2001; 28: 55-61
        • Fessler K.B.
        Social outcomes of early childbearing: important considerations for the provision of clinical care.
        J Midwifery Womens Health. 2003; 48: 178-185