Biomedical subjects

T J Mathews

Publications and source records attributed to T J Mathews.

At least 19 recordsLinked to original sources

PubMed2006

Infant mortality statistics from the 2003 period linked birth/infant death data set.

OBJECTIVES: This report presents 2003 period infant mortality statistics from the linked birth/infant death data file by a variety of maternal and infant characteristics. The linked file differs from the mortality file, which is based entirely on death certificate data. METHODS: Descriptive tabulations of data are presented and interpreted. Excluding rates by cause of death, the infant mortality rate is now published with two decimal places. RESULTS: The U.S. infant mortality rate was 6.84 infant deaths per 1,000 live births in 2003, a return to the rate in 2001, compared with 6.95 in 2002. Infant mortality rates ranged from 4.83 per 1,000 live births for Asian or Pacific Islander mothers to 13.60 for non-Hispanic black mothers. Among Hispanics, rates ranged from 4.57 for Cuban mothers to 8.18 for Puerto Rican mothers. Infant mortality rates were higher for those infants whose mothers were born in the 50 States and the District of Columbia, were unmarried, or smoked during pregnancy. Infant mortality was also higher for male infants, multiple births, and infants born preterm or at low birthweight. Infants born at the lowest birthweights and gestational ages have a large impact on overall U.S. infant mortality. Nearly one-half (49 percent) of all infant deaths in the U.S. in 2003 occurred to the 0.8 percent of infants whose birthweight was less than 1,000 grams. The three leading causes of infant death--Congenital malformations, low birthweight, and SIDS--taken together accounted for 45 percent of all infant deaths. For infants of non-Hispanic black mothers, the cause-specific infant mortality rate for low birthweight was nearly four times that for infants of non-Hispanic white mothers. For infants of non-Hispanic black and American Indian mothers, the SIDS rates were more than double the rate for non-Hispanic white mothers.

Birth Certificates↗

PubMed2006

Racial differences in infant mortality attributable to birth defects in the United States, 1989-2002.

BACKGROUND: The objective is to study racial differences in infant mortality attributable to birth defects (IMBD) in the United States. METHODS: We analyzed 1989-1991 and 1995-2002 linked birth/death files for trends and racial differences in IMBD by selected categories of birth defects for infants of non-Hispanic white, non-Hispanic black, and Hispanic mothers. RESULTS: In 1989-2002, the IMBD rates declined. However, the decline in postneonatal mortality attributable to birth defects (PMBD) rate was significantly slower than that of overall postneonatal mortality. The adjusted rate ratio for non-Hispanic black and Hispanic versus non-Hispanic white for neonatal mortality attributable to birth defects (NMBD) remained unchanged from 1989-1991 through 2000-2002. For PMBD, it increased from 0.97 (95% confidence interval [CI], 0.90-1.13) in 1989-1991 to 1.12 (95% CI, 1.04-1.21) in 2001-2002 and from 1.08 (95% CI, 1.00-1.16) to 1.18 (95% CI, 1.10-1.27) for non-Hispanic black and Hispanic, respectively. Infant mortality due to cardiovascular and central nervous system defects were the main contributors to the increased racial disparities in PMBD rates. CONCLUSIONS: The disparity in PMBD between infants of non-Hispanic black and Hispanic mothers and infants of non-Hispanic white mothers increased significantly from 1989-1991 to 2000-2002. Further studies are needed to assess the extent to which delays in care or lack of access to care for infants with birth defects might be contributing to the disparity in IMBD.

Cardiovascular Abnormalities↗

PubMed2006

Annual summary of vital statistics: 2004.

The crude birth rate in 2004 was 14.0 births per 1000 population, the second lowest ever reported for the United States. The number of births and the fertility rate (66.3) increased slightly (by <1%) from 2003 to 2004. Fertility rates were highest for Hispanic women (97.7), followed by Asian or Pacific Islander (67.2), non-Hispanic black (66.7), Native American (58.9), and non-Hispanic white (58.5) women. The birth rate for teen mothers continued to fall, dropping 1% from 2003 to 2004 to 41.2 births per 1000 women aged 15 to 19 years, which is another record low. The teen birth rate has fallen 33% since 1991; declines were more rapid for younger teens aged 15 to 17 (43%) than for older teens aged 18 to 19 (26%). The proportion of all births to unmarried women is now slightly higher than one third. Smoking during pregnancy declined slightly from 2003 to 2004. In 2004, 29.1% of births were delivered by cesarean delivery, up 6% since 2003 and 41% since 1996 (20.7%). The primary cesarean delivery rate has risen 41% since 1996, whereas the rate of vaginal birth after a previous cesarean delivery has fallen 67%. The use of timely prenatal care was 84.0% in both 2003 and 2004. The percentage of preterm births rose to 12.5% in 2004 from 10.6% in 1990 and 9.4% in 1981. The percentage of low birth weight births also increased to 8.1% in 2004, up from 6.7% in 1984. Twin birth rate and triplet/+ birth rates increased by 1% and <1%, respectively, from 2002 to 2003. Multiple births accounted for 3.3% of all births in 2003. The infant mortality rate was 7.0 per 1000 live births in 2002 compared with 6.8 in 2001. The ratio of the infant mortality rate among non-Hispanic black infants to that for non-Hispanic white infants was 2.4 in 2002, the same as in 2001. The United States continues to rank poorly in international comparisons of infant mortality. Expectation of life at birth reached a record high of 77.6 years for all gender and race groups combined. Death rates in the United States continue to decline, with death rates decreasing for 8 of the 15 leading causes. Death rates for children < or =19 years of age declined for 7 of the 10 leading causes in 2003. The death rates did not increase for any cause, and rates for heart disease, influenza, and pneumonia and septicemia did not change significantly for children as a group. A large proportion of childhood deaths, however, continue to occur as a result of preventable injuries.

Birth Rate↗

PubMed2006

Birth and fertility rates for states by Hispanic origin subgroups: United States, 1990 and 2000.

OBJECTIVES: This report presents U.S. and State-level data on births, birth rates, and fertility rates for Hispanic origin subgroups for 1990 and 2000. Data for non-Hispanic whites and non-Hispanic blacks are provided for comparison. METHODS: Data are presented in detailed tables, graphs, and maps. RESULTS: Between 1990 and 2000, the total U.S. Hispanic population increased 58 percent, from 22,353,999 to 35,305,818. Over the same period of time, births to Hispanic mothers increased 37 percent, from 595,073 to 815,868. The smaller increases in births compared with the population resulted in a falling birth rate among Hispanic mothers (26.7 in 1990 to 23.1 births per 1,000 total population in 2000). Birth and fertility rates for Mexican, Puerto Rican, and Cuban mothers all fell between 1990 and 2000. Among the Hispanic subgroups, fertility rates in 2000 ranged from 105.1 births per 1,000 women aged 15-44 years for Mexican women to 49.3 for Cuban women. Differences in fertility exist not only between Hispanic subgroups but also within groups among States. For example, total fertility rates for Puerto Rican mothers, which estimates the number of children a group of 1,000 women will have in their lifetime, ranged in 2000 from 1,616.5 in New York to 2,403.0 in Pennsylvania.

Adolescent↗

PubMed2005

Trend analysis of the sex ratio at birth in the United States.

OBJECTIVES: This report presents total sex ratios at birth from 1940 to 2002, for race starting in 1970, for Hispanic origin groups starting in 1989, for live birth order starting in 1943, and for age of mother for the full time period. METHODS: Descriptive tabulations of sex ratios using the birth data set are presented and interpreted. Joinpoint regression analysis is used to detect changes in the sex ratio over time. RESULTS: The United States sex ratio at birth had three significant transitions from 1940 to 2002 (1942, 1959, and 1971). White women were the only race group to have any significant changes in the sex ratio between 1970 and 2002 (1972, 1976, and 1988). Between 1940 and 2002 significant transitions in sex ratios occurred to women aged 20-24 (1942, 1966, 1974, and 1987); 25-29 (1961 and 1968); 35-39 (1965 and 1976); and 40-44 years (1967).

Birth Rate↗

PubMed2005

Explaining the 2001-02 infant mortality increase: data from the linked birth/infant death data set.

The U.S. infant mortality rate increased from 6.8 infant deaths per 1,000 live births in 2001 to 7.0 in 2002, the first increase in more than 40 years. From 2001 to 2002 infant mortality rates increased for very low birthweight infants as well as for preterm and very preterm infants. Although infant mortality rates for very low birthweight infants increased, most of the increase in the infant mortality rate from 2001 to 2002 was due to a change in the distribution of births by birthweight and, more specifically, to an increase in infants born weighing less than 750 grams (1 lb 10 1/2 oz). The majority of infants born weighing less than 750 grams die within the first year of life; thus, these births contribute disproportionately to the overall infant mortality rate. Increases in births at less than 750 grams occurred for non-Hispanic white, non-Hispanic black, and Hispanic women. Most of the increase occurred among mothers 20-34 years of age. Although multiple births contributed disproportionately, most of the increase in births at less than 750 grams occurred among singletons. Three hypotheses were evaluated to assess their possible impact on the increase in less than 750-gram births: first, possible changes in the reporting of births or fetal deaths; second, possible changes in the risk profile of births; and third, possible changes in medical management of pregnancy. Although each of these factors may have contributed to the increase, the relative effects of these and other factors remain unclear. More-detailed studies are needed to further explain the 2001-02 infant mortality increase.

Birth Weight↗

PubMed2005

Explaining the 2001-2002 infant mortality increase in the United States: data from the linked birth/infant death data set.

The U.S. infant mortality rate (IMR) increased from 6.8 infant deaths per 1,000 live births in 2001 to 7.0 in 2002, the first increase in more than 40 years. From 2001 to 2002, IMR increased for very low birthweight infants as well as for preterm and very preterm infants. Although IMR for very low birthweight infants increased, most of the increase in IMR from 2001 to 2002 was due to a change in the distribution of births by birthweight and, more specifically, to an increase in infants born weighing less than 750 grams. The majority of infants born at less than 750 grams die within the first year of life; thus, these births contribute disproportionately to overall IMR. Increases in births at less than 750 grams occurred fornon-Hispanic white, non-Hispanic black, and Hispanic women. Most of the increase occurred among mothers 20 to 34 years of age. Although multiple births contributed disproportionately, most of the increase in births at less than 750 grams occurred among singletons. Three hypotheses were evaluated to assess their possible impact on the increase in less than 750-gram births: possible changes in (1) the reporting of births or fetal deaths, (2) the risk profile of births, and (3) medical management of pregnancy. Although each of these factors may have contributed to the increase, the relative effects of these and other factors remain unclear. More detailed studies are needed to further explain the 2001-2002 infant mortality increase.

Birth Rate↗

PubMed2004

Infant mortality statistics from the 2002 period: linked birth/infant death data set.

OBJECTIVES: This report presents 2002 period infant mortality statistics from the linked birth/infant death data file by a variety of maternal and infant characteristics. The linked file differs from the mortality file, which is based entirely on death certificate data. METHODS: Descriptive tabulations of data are presented and interpreted. RESULTS: The U.S. infant mortality rate increased from 6.8 infant deaths per 1000 live births in 2001 to 7.0 in 2002. The rate for infants of non-Hispanic white mothers was 5.7 in 2001 compared with 5.8 in 2002. The rate for infants of non-Hispanic black mothers was 13.5 in 2001 compared with 13.9 in 2002. Neither of the changes for non-Hispanic white nor non-Hispanic black was significant. Between 2001 and 2002, overall cause-specific rates increased 5 percent for low birthweight and 14 percent for maternal complications. The rate rose significantly for infants of mothers who smoked, 10.5 to 11.1. It also increased significantly from 10.7 to 11.5 for infants of mothers aged 15-17 years. The rate dropped significantly for triplet births, 71.4 to 60.1. Infant mortality rates ranged from 3.0 per 1000 live births for Chinese mothers to 13.9 for non-Hispanic black mothers. Among Hispanics, rates ranged from 3.7 for Cuban mothers to 8.2 for Puerto Rican mothers. Infant mortality rates were higher for those infants whose mothers were born in the 50 States and the District of Columbia, were unmarried, or smoked during pregnancy. Infant mortality was also higher for male infants, multiple births, and infants born preterm or at low birthweight. The three leading causes of infant death-Congenital malformations, low birthweight, and Sudden infant death syndrome (SIDS)-taken together accounted for 45 percent of all infant deaths. For infants of non-Hispanic black mothers, the cause-specific infant mortality rate for low birthweight was nearly four times that for infants of non-Hispanic white mothers. For infants of non-Hispanic black and American Indian mothers, the SIDS rates were at least double the rate for non-Hispanic white mothers. A more intensive analysis of the rise in the infant mortality rate utilizing information on maternal and infant health risk factors available in the linked birth/infant death and fetal death data files is forthcoming.

Adult↗

PubMed2004

Trends in characteristics of births by State: United States, 1990, 1995, and 2000-2002.

OBJECTIVE: This report presents U.S. and State-level data on births, birth rates, fertility rates, sex ratio, marital status, and educational attainment by race and Hispanic origin for 1990, 1995, and 2000-2002. METHODS: Data are presented in detailed tables, summary tables, maps, and graphs. RESULTS: In 2002 there were 4,021,726 live births in the United States, 136,486 fewer than in 1990. Despite a slight decline in the number of births nationwide, a few States witnessed significant increases in the number of live births with most of these States located in the western United States. Some of the westward shift in number of births is attributable to a growing population and some to the age and race composition of the individual States. However, real differences in fertility by State persist even when the effects of age structure and race and ethnic composition of the States' population are taken into account. This report also presents data on sex ratios, percentage unmarried, and educational attainment of mothers. Several observations from these data are noteworthy. The proportion of births to unmarried mothers increased nationally and in every State between 1990 and 2002. Nationally the percentage of mothers with fewer than 12 years of education fell, and the percentage with 16 or more years increased for all racial and ethnic groups. However, at the State level, the percentage of women with fewer than 12 years of education increased for nearly a quarter of the States, despite near universal increases in the percentage of women with 16 or more years of education.

Adult↗

PubMed2003

Infant mortality statistics from the 2001 period linked birth/infant death data set.

OBJECTIVES: This report presents 2001 period infant mortality statistics from the linked birth/infant death data set (linked file) by a variety of maternal and infant characteristics. METHODS: Descriptive tabulations of data are presented and interpreted. RESULTS: Infant mortality rates ranged from 3.2 per 1,000 live births for Chinese mothers to 13.3 for black mothers. Among Hispanics, rates ranged from 4.2 for Cuban mothers to 8.5 for Puerto Rican mothers. Infant mortality rates were higher for those infants whose mothers were born in the 50 States and the District of Columbia, were unmarried, or smoked during pregnancy. Infant mortality was also higher for male infants, multiple births, and infants born preterm or at low birthweight. The three leading causes of infant death--Congenital malformations, low birthweight, and Sudden infant death syndrome (SIDS)--taken together accounted for 44 percent of all infant deaths. Cause-specific mortality rates varied considerably by race and Hispanic origin. For infants of black mothers, the cause-specific infant mortality rate for low birthweight was nearly four times that for infants of white mothers. Between 1995 and 2001, the overall infant mortality rate declined by 10.5 percent; significant declines ranged from 8.2 percent for infants of non-Hispanic black mothers to 14.3 percent for infants of Hispanic mothers. The SIDS rate declined by 11 percent from 2000 to 2001. For infants of black and American Indian mothers, the SIDS rates were 2.2 and 2.8 times that for non-Hispanic white mothers.

Adult↗

PubMed2003

Trends and variations in smoking during pregnancy and low birth weight: evidence from the birth certificate, 1990-2000.

OBJECTIVE: This study compares patterns of tobacco use during pregnancy over time and across population subgroups and examines the impact of maternal smoking on the incidence of low birth weight (LBW). The study also evaluates the use of birth certificates to monitor prenatal smoking. METHODS: The birth certificates of all states (except California) and the District of Columbia for 2000 provided to Centers for Disease Control and Prevention's National Center for Health Statistics were analyzed. Trends in maternal smoking were examined with data from birth certificates and other relevant sources. RESULTS: Smoking during pregnancy was reported for 12.2% of women who gave birth in 2000, down 37% from 1989 (19.5%), when this information was first collected on birth certificates. Throughout the 1990s, prenatal smoking rates were highest for older teenagers and women in their early 20s. Among population subgroups, the highest rates were reported for non-Hispanic white women who attended but did not complete high school. The incidence of LBW among singleton infants who were born to smokers was double that for nonsmokers. This relationship was observed in all age groups, for births to Hispanic and non-Hispanic white and black women, and within educational attainment subgroups. Even light smoking (<5 cigarettes daily) was associated with elevated rates of LBW. CONCLUSION: Although prenatal smoking may be underreported on the birth certificate, the trends and variations in smoking based on birth certificate data have been confirmed with data from other sources. Birth certificate data can be useful in monitoring prenatal smoking patterns. Changes in the birth certificate questions that are to be implemented beginning in 2003 will help to clarify the levels and changes in smoking behavior during pregnancy so that smoking cessation programs can be more effectively designed to meet the needs of the populations at risk.

Adolescent↗

PubMed2002

Mean age of mother, 1970-2000.

OBJECTIVES: This report presents trends in the mean age of mothers giving birth for the United States for the last three decades. Data are presented by live-birth order, race, Hispanic origin, and State of residence of the mother. METHODS: Descriptive tabulations and graphs of the trends in the mean age of mother are discussed. RESULTS: The mean age of mother has increased steadily in the United States over the last three decades. Mothers having their first and second live births had the largest increase in mean age. Among racial and Hispanic origin subgroups, Japanese women had the highest mean age in 2000. Puerto Rican women had the lowest mean age. Massachusetts had the highest mean age in 2000 and Mississippi had the lowest.

Adolescent↗

PubMed2002

Spina bifida and anencephaly prevalence--United States, 1991-2001.

Spina bifida and anencephaly are serious birth defects. To reduce the occurrence of these birth defects, the Food and Drug Administration authorized the fortification of all enriched cereal grain products with folic acid in March 1996, with compliance mandatory by January 1998. This report reviews data reported to CDC's National Center for Health Statistics (NCHS) regarding spina bifida and anencephaly prevalence for live births in the United States during 1991-2001. Since 1989, NCHS has compiled birth defect data from checkboxes that appear on birth certificates. For consistency in trends, this report uses data for 1991-2001 from all U.S. reporting areas except Maryland, New Mexico, and New York. Data for 2001 are preliminary. During 1996-2001, a 23% decline occurred in neural tube defects (spina bifida and anencephaly combined). Spina bifida declined 24% during this period, and anencephaly declined 21%. The United States has experienced declines in spina bifida and anencephaly cases since folic acid fortification of all enriched cereal grain products. The observed declines have translated into approximately 920 infants being born without these serious defects each year. Continued monitoring of the occurrence of spina bifida and anencephaly will be necessary to evaluate the effectiveness of folic acid fortification.

Anencephaly↗

PubMed2002

Infant mortality statistics from the 2000 period linked birth/infant death data set.

OBJECTIVES: This report presents the 2000 period infant mortality statistics from the linked birth/infant death data set (linked file) by a variety of maternal and infant characteristics. METHODS: Descriptive tabulations of data are presented and interpreted. RESULTS: Infant mortality rates ranged from 3.5 per 1,000 live births for Chinese mothers to 13.5 for black mothers. Among Hispanics, rates ranged from 4.5 for Cuban mothers to 8.2 for Puerto Rican mothers. Infant mortality rates were higher for those infants whose mothers had no prenatal care, were teenagers, had 9-11 years of education, were unmarried, or smoked during pregnancy. Infant mortality was also higher for male infants, multiple births, and infants born preterm or at low birthweight. The three leading causes of infant death--Congenital malformations, low birthweight, and Sudden infant death syndrome (SIDS)--taken together accounted for 45 percent of all infant deaths in the United States in 2000. Cause-specific mortality rates varied considerably by race and Hispanic origin. For infants of black mothers, the infant mortality rate for low birthweight was nearly four times that for white mothers. For infants of black and American Indian mothers, the SIDS rates were 2.4 and 2.3 times that for non-Hispanic white mothers.

Birth Weight↗

PubMed2002

Teenage births in the United States: state trends, 1991-2000, an update.

OBJECTIVES: This report provides State-specific birth rates for teenagers for 1991 and 2000, and the percent change between the time periods. METHODS: Tabular and graphical description of trends in teenage birth rates by age group for each State and territory. RESULTS: Birth rates for teenagers 15-19 years declined significantly in all States, the Virgin Islands and Guam, between 1991 and 2000. Declines by State ranged from 12 to 39 percent. Rates also fell significantly for teenage subgroups 15-17 and 18-19 years.

Adolescent↗

PubMed2002

Infant mortality statistics from the 1999 period linked birth/infant death data set.

OBJECTIVES: This report presents 1999 period infant mortality statistics from the linked birth/infant death data set (linked file) by a variety of maternal and infant characteristics. METHODS: Descriptive tabulations of data are presented. RESULTS: In general, mortality rates were lowest for infants born to Chinese and Japanese mothers (2.9 and 3.4 per 1,000, respectively). Infants of Cuban, Central and South American, Mexican, and non-Hispanic white mothers had low rates, while rates were higher for infants of Puerto Rican and highest for non-Hispanic black mothers (13.9). Filipino mothers also had low rates. Rates were high for infants of Hawaiian and American Indian mothers. Infant mortality rates were higher for those infants whose mothers had no prenatal care, were teenagers, had 9-11 years of education, were unmarried, or smoked during pregnancy. Infant mortality was also higher for male infants, multiple births, and infants born preterm or at low birthweight. The three leading causes of infant death--Congenital malformations, low birthweight, and Sudden infant death syndrome (SIDS)--taken together accounted for 45 percent all infant deaths in the United States in 1999. Cause-specific mortality rates varied considerably by race and Hispanic origin. For infants of black mothers, the infant mortality rate for low birthweight was four times that for white mothers. For infants of American Indian mothers, the SIDS rate was 2.4 times that for non-Hispanic white mothers. SIDS rates for infants of Hispanic and Asian or Pacific Islander mothers, were 40-50 percent lower than those for non-Hispanic white mothers.

Birth Certificates↗

PubMed2002

Trends and characteristics of induced labour in the United States, 1989-98.

Induction of labour is one of the fastest growing medical procedures in the United States. In 1998, 19.2% of all US births were a product of induced labour, more than twice the 9.0% in 1989. Induction of labour has been efficacious in the management of post-term pregnancy and in expediting delivery when the mother or infant is sufficiently ill to make continuation of the pregnancy hazardous. However, the recent rapid increase in induction, and particularly the doubling of the induction rate for preterm pregnancies (from 6.7% in 1989 to 13.4% in 1998), has generated concern among some clinicians. The present study uses vital statistics natality data to examine the epidemiology of induced labour in the US. Multivariable analysis is used to examine the probability of having an induced delivery in relation to a wide variety of socio-demographic and medical characteristics, and also in relation to relative indications and contraindications for induced labour as outlined by the American College of Obstetricians and Gynecologists (ACOG). Induction rates were higher for women who were non-Hispanic white, college educated, born in the US, primaparae and those with intensive prenatal care utilisation. Induction rates were also higher for women with various medical conditions including hypertension, eclampsia and renal disease. For non-Hispanic white women with singleton births, 59% of the increase in the preterm birth rate from 1989 to 1998 can be accounted for by the increase in preterm inductions. The adjusted odds ratio for neonatal mortality among preterm births with induced labour was 1.20 [95% confidence interval 1.11, 1.31]. The rapid increase in induction rates, particularly among preterm births, marks a shift in the obstetric management of pregnancy. More detailed studies are needed to examine physician decision-making protocols, particularly for preterm induction, and to assess the impact of these practice changes on patient outcomes.

Adult↗

PubMed2001

Births to teenagers in the United States, 1940-2000.

OBJECTIVES: This report presents trends in national birth rates for teenagers, with particular focus on the decade of the 1990s. The percent change in rates for 1991-2000 is presented for the United States, and the change for 1991-99 is presented for States. METHODS: Tabular and graphical descriptions of the trends in teenage birth rates for the Nation and each State, by age group, race, and Hispanic origin, are discussed. RESULTS: Birth rates for teenagers 15-19 years generally declined in the United States since the late 1950s, except for a brief, but steep, upward climb in the late 1980s until 1991. The 2000 rate (49 births per 1,000) is about half the peak rate recorded in 1957 (96 per 1,000). Still the U.S. rate is considerably higher than rates for other developed countries. During the 1990s rate declines were especially large for black teenagers. State-specific rates fell significantly in all States for ages 15-19 and 15-17 years, and in all but three States for ages 18-19 years. Overall the range of decline in State rates for ages 15-19 years was 11 to 36 percent. For teenagers 15-17 years, the range of decline by State was 13 to 43 percent. Reductions by State were largest for black teenagers 15-19 years, with rates falling 40 percent or more in seven States. The factors accounting for these declines include decreased sexual activity reflecting changing attitudes towards premarital sex, increases in condom use, and adoption of newly available hormonal contraception, implants, and injectables.

Adolescent↗