Introduction

The United States has made substantial progress toward ensuring the health and vitality of pregnant mothers and new-born children. Since 1960, maternal and infant mortality rates have declined steadily. From 1960 to 1982, maternal mortality rates declined 72% and infant mortality rates declined 54%. However, these rates of decline slowed during the 1980s. Infant mortality had been declining at a rate of 5%-6% a year during the 1970s, but declined only 2.7% per year for 1982-1984. The maternal mortality rate was essentially unchanged for 1982-1983, though provisional data indicate a decline for 1983-1984 from 8.0 to 5.95 maternal deaths per 100,000 live births. Between 1982 and 1983, the post-neonatal mortality rate increased for the first time in five years.

The first year of life is the most hazardous until the age 65. The principal threats to infant survival are congenital anomalies, sudden infant death syndrome, respiratory distress syndrome and low birthweight. Improved neo-natal intensive care has improved the survival of low birth-weight infants, as evidenced by a 47% decline in neonatal mortality rates from 1965 to 1980. However, the proportion of infants born of low birthweight remained the same from 1980 to 1983. Teenage, Black and unmarried mothers account for a disproportionately high percentage of low birthweight births. Over the past 20 years, the Black infant mortality rate has remained nearly double that of white infants (the 1983 Black infant mortality rate was 1.98 times the rate for white infants.) The availability and accessibility of care to those in greatest need (teenage, Black, unmarried and poor mothers) may be threatened by the changing medical economic environment that is pressuring doctors and hospitals to cut back on high-risk obstetrical care.

Prevalence

Birth Rates

In 1980, 1.6% of the U.S. population was less than 1 year of age, down from 2.3% in 1960.

In 1980, 10.4% of the U.S. population under 1 year of age was of Spanish origin, up from 6% in 1970. (Note, this includes infants also identified as Black, white and other).

An estimated 3,749,000 babies were born in 1985. This represents a 1.4% increase over the 3,697,000 babies born in 1984.

The birth rate during 1985 was 15.7 live births per 1,000 population, the same rate as for 1984.

The fertility rate for 1985 was 66.1 live births per 1,000 women ages 15-44, up slightly from 66.0 in 1984, but below the rate of 68.4 in 1980.

The number of live births per 1,000 women of childbearing age declined between 1965 and 1984 for all age categories except for women 10-14 years of age.

Close to 25% of Black infants born in 1982 were born to teenage mothers (19 years of age or younger), compared to 12% of white infants, 18% of Hispanic infants, 6% of Asian infants, and 22% of Native American infants.

Unmarried Black women bear children about four times as frequently as unmarried white women even though the rate of childbearing among unmarried Black women has decreased slightly since 1975, while the rate for whites has increased.

Since 1975, the educational attainment for mothers of all ages has increased.

Maternal Mortality

In 1983, 290 women died of causes related to pregnancy, childbirth and the puerperium for a rate of 8.0 deaths per 100,000 live births. However, provisional data from 1984 indicates 220 maternal deaths for a maternal death rate of 5.95, the lowest ever recorded.

The 1983 maternal mortality rate for Black women (18.3 deaths per 100,000 births) was 3 times the rate for white women (5.9).

Health Practices During Pregnancy

According to a 1980 National Natality Survey, 31% of all married mothers and 47% of teenage married mothers were cigarette smokers prior to becoming pregnant.

18% of smoking mothers in the 1980 National Natality Survey stopped smoking during pregnancy, and 30% of drinking mothers were able to stop during pregnancy.

The 1980 National Natality Survey revealed that less than 1/2 (47.4%) of women neither smoked nor drank during pregnancy.

Smoking during pregnancy is associated with a reduction in birthweight of offspring of 150-250 gms.

Women who gain less than 14 pounds during pregnancy produce infants of low birthweight four times more frequently than women who gain 30-35 pounds. Black mothers are two times more likely than white mothers to gain less than 16 pounds during pregnancy, according to the 1980 National Natality and Fetal Mortality Surveys.

Mortality

The major causes of death before age one are congenital anomalies, sudden infant death syndrome, respiratory distress syndrome, and disorders related to short gestation and low birthweight. Significant gaps exist between Blacks and whites for all causes of infant death except congenital anomalies. Black infants are nearly 3.5 times more likely to die as a result of disorders related to short gestation and low birth weight, three times more likely to die as a result of pneumonia or influenza, and roughly two times more likely to die as a result of maternal complications, sudden infant death syndrome, accidents and adverse effects, intrauterine hypoxic and birth asphyxia, respiratory distress syndrome, and infections specific to the perinatal period.

Babies born to women who receive no prenatal care are three times more likely to die in infancy.

A study comparing infant death rates of low birthweight infants and normal birthweight infants revealed that a low birthweight, white infant is 41.5 times more likely to die in the neonatal period and 5.4 times more likely to die in the postneonatal period than a normal birthweight, white infant.

In 1984, the infant mortality rate (deaths per 1,000 live births before age one) reached a low of 10.6. down from 11.2 in 1983.

The infant mortality rate for Black infants is about two times that of white infants.

Compared to other nations of the world, the United States' infant mortality rate was 14th in 1984, behind Finland and Japan (7); Sweden, Norway, Switzerland, Netherlands and Denmark (8); Canada and France (9); Australia, Spain, United Kingdom and Hong Kong (10).

There were an estimated 39,100 infant deaths in the U.S. in 1984. Nearly two-thirds of all infant deaths occur in the first 4 weeks of life (neonatal period).

Over one-half of all infant deaths in the U.S. in 1983 were from one of 4 categories: congenital anomalies (21.5%); sudden infant death syndrome (13.0%); respiratory distress syndrome (9.0%); and disorders relating to short gestation and low birthweight (8.0%).

A comparison of infant mortality rates by race reveals little difference for mortality from congenital anomalies, but large differences for other causes: the Black infant mortality rate is 3.4 times the white rate for disorders relating to short gestation and low birthweight, 3.0 times the white rate for pneumonia and influenza, 2.1 times the white rate for SIDS and 2.0 times the white rate for accidents and adverse effects.

The neonatal mortality rate for Blacks has been roughly 2 times that for whites since 1975, up from 1.7 times as high in 1970 and 1.6 times in 1960.

The neonatal death rate is substantially higher for Blacks than for whites for all causes except congenital anomalies.

The postneonatal mortality rate has not declined as rapidly as the neonatal mortality rate. Since 1975, the rate for Blacks has been roughly two times that for whites.

Sudden infant death syndrome (SIDS) is the most important cause of postneonatal mortality. In 1982, the rate for SIDS was 132.2 per 100,000 live births, accounting for one-third of infant deaths in the postneonatal period.

The postneonatal death rate is substantially higher for Blacks than for whites for all causes.

Morbidity

1 in 5 infants suffer at least 1 major health problem during the first year of life.

1 in 10 infants are hospitalized during the first year of life.

Chronic illness and congenital anomalies account for most pediatric admissions to hospitals.

Low Birthweight and Prematurity

Two-thirds of the deaths in the 1st month of life and 60% of all infant deaths occur to infants of low birthweight (less than 2,500 grams or 5.5 pounds).

In 1983, 9.6% of all babies were born preterm (prior to 37 weeks gestation).

In 1983, Black infants were more than 2 times as likely to be born preterm (17.4%) than white infants (8.0%).

The principal risk factors associated with low birthweight are: maternal age (teenage or age 40 and over), race, maternal smoking, maternal alcohol consumption, lack of early or adequate prenatal care, low maternal educational attainment, low pre-pregnancy weight and height, inadequate weight gain during pregnancy, and short intervals between pregnancies.

Low birthweight infants are not only at greater risk of dying during the first year of life, they are also at greater risk of developing long-term disabilities such as cerebral palsy, autism, retardation, developmental delays, and vision and hearing disabilities.

Between 1982 and 1983, the percentage of babies born at low birthweight increased slightly nationwide, reversing a gradual downward trend since 1978. The percentage of babies born at very low birthweight has remained virtually unchanged since 1975, but the percentage of Black infants born at very low birthweight has increased slightly.

In 1983, 6.8% of all infants born in the U.S. had a low birthweight.

A study comparing infant death rates of low birthweight infants and normal birthweight infants revealed that a low birthweight, white infant is 41.5 times more likely to die in the neonatal period and 5.4 times more likely to die in the postneonatal period than a normal birthweight, white infant.

Low birthweight infants are 3 times more likely to develop adverse neurological sequelae (e.g., cerebral palsy, seizure disorders), and are at twice the risk of having congenital anomalies.

The percentage of low birthweight births in the U.S. (6.8%) is considerably higher than that of several other developed countries, including Norway (3.25%), Sweden (4.03%) and Switzerland (5.1%).

In 1983, the proportion of low birthweight births among Blacks (12.6%) was more than double that for whites (5.7%), while the proportion for Native Americans (6.4%) remains below the national average (6.8%).

The racial differential in low birthweight infants results primarily from term or posterm births: about 40% of both Black and white preterm infants are of low birthweight, yet 6% of Black births at term or later are of low birthweight, compared to 2.6% of comparable white births.

The risk of having a lowbirthweight infant is three times as high for women with no prenatal care as it is for women who begin prenatal care during the first trimester.

In 1983, only 14% of all births were to teenagers, yet over 19% of all low birthweight babies had teenage mothers.

Hospital care for low birthweight babies costs an average of $1,000 per day.

Breastfeeding

61.4% of infants in the U.S. are breastfed, yet racial differences are marked: 64% of white infants, 32% of Black infants and 54% of Hispanic infants are ever breastfed.

40% of all infants in the U.S. are breastfed for three months or longer, including 42% of white infants and 20% of black infants.

Congenital Malformations

Birth defects remain a major cause of morbidity in the United States. The Birth Defects Monitoring Program reported the following rates of congenital malformation (per 10,000) total births in 1982: anencephaly 3.3, spina bifida 4.8, ventricular septal defect 14.7, patent ductus arteriases 26.9, hydrocephalus 5.5, cleft lip with or without cleft palate 8.8, Down's syndrome 7.9.

By the end of the first year of life, of single born infants: 2% show evidence of severe impairment from a congenital anomaly or marked development delay, 7% show evidence of moderate impairment, and 4% have evidence of a congenital anomaly that is not likely to produce permanent or significant impairment.

Of those children admitted to the hospital during the first year of life, one in six admissions is the result of a congenital anomaly or developmental disability.

Congenital anomalies are 3-4 times higher among offspring of untreated diabetic women than among children of non-diabetic women.

Public and Professional Awareness

In a 1985 National Health Interview Survey, 70%-80% of those questioned recognized that cigarette smoking during pregnancy is associated with an increased risk of low birthweight, premature birth and miscarriage.

63% of females and 52% of males questioned in a 1985 survey, had never heard of fetal alcohol syndrome.

78% of college-educated mothers in 1983, breastfed their infants compared to 41% of mothers with a grade school education.

85% of the U.S. public in a 1985 survey recognized the association of heavy drinking during pregnancy with an increased risk of birth defects, miscarriage, low birthweight and mental retardation of the newborn.

Service Delivery

Only 56% of white and 45% of Black teen mothers in 1983 received any prenatal care during the first trimester of their prenancies.

20.6% of white mothers of all ages and 38.5% of Black mothers of all ages in 1983 failed to receive prenatal care in the first trimester.

The percentage of births in which prenatal care occurred in the third trimester only, or not at all, increased to 4.6% for whites and 9.7% for Blacks in 1983.

In 1983, 98.8% of white infants and 99.3% of Black infants were born in a hospital. Physicians attended 97.7% of deliveries and midwives 2.0% (an increase from 1.6% in 1981).

Hospitals in 1983 discharged more patients with the diagnosis of "delivery" (4.0 million patients) than any other diagnostic category.

In 1983, the average length of hospital stay for normal deliveries was 2.8 days, and for complicated deliveries (breech, prematurity, preeclampsia, Caesarean and others) was 4.2 days.

All 50 states and the District of Columbia have newborn screening programs that at a minimum test for phenylketonuria (PKU) and hypothyroidism. About 94% of live births (in reporting states) were tested for PKU and hypothyroidism.

In 1986, $1.56 billion was appropriated for the Women, Infants and Children (WIC) supplemental feeding program, which serves 3.3 million persons monthly.

Two-thirds of children living in poverty are completely uninsured for health care services or are insured only part of the year.

For children under age one, 55% of visits to pediatricians is for non-illness care. Visits for the treatment of acute medical problems account for 38% of physician contacts and visits for the care of chronic health problems account for 5%.

The principal reason children under age one come in contact with a physician is for routine well baby care.

10% of poor Black children do not see a physican in the first year of life for any reason, even though the American Academy of Pediatrics recommends nine health examinations during the first two years of life.

Significant Trends

Infant, Neonatal and Postneonatal Mortality

From 1981 to 1983, the rate of decline of neonatal and infant mortality slowed. Postneonatal mortality increased 3% from 1982 to 1983, reflecting primarily an increase in the Black postneonatal mortality rate.

The difference between Black and white infant mortality rates is not changing, Black infant mortality rates are 2 times those for white infants.

At the turn of the century, postneonatal deaths (between 28 days to 1 year of age) accounted for most infant deaths, but today neonatal deaths (within the first 28 days of life) predominate.

The decline in postneonatal mortality since the mid-1930s is thought to be reflective of improved living conditions, child care, and the widespread availability of medical care for treatable conditions such as infections.

Low Birthweight Infants

The 47% decline in neonatal mortality rates from 1965 to 1980 was a result of improved neonatal intensive care. The proportion of infants born at low birthweight has declined only 18% from 1965 to 1983, from 8.3% to 6.8% of births.

From 1980 through 1983, the percentage of infants born at low birthweight (6.8%) remained unchanged. From 1982 to 1983, the percentage of Black infants born with low birthweight increased slightly (from 12.4% to 12.6%). During the decade from 1973 to 1983, the Black/white ratio of low birthweight births increased from 2.08 to 2.21.

Breastfeeding

Breastfeeding has been shown to prevent both malnutrition and obesity in infants and may provide the infant with short-term immunity from some diseases. Between 1970 and 1980, breastfeeding more than doubled, from 24% of babies born to 53%. The increase was greater among white mothers than Black mothers; 57% of white mothers breastfed their infants in 1980 while only 25% of Black mothers did so.

Congenital Malformation

From 1970 to 1982, the reported incidences of ventricular septal defect and patent ductus arteriosis have more than tripled. For the same time period, the incidence of anencephaly has declined 41% and the incidence of spina bifida has declined 34%.

In 1983, from 1800 to 2400 babies with FAS were predicted to be born, and another 36,000 newborns would be affected by a range of less severe adverse alcohol-related effects.

Maternal alcohol abuse during pregnancy appears to be the most frequently known terotogenic cause of mental retardation in the western world.

Maternal drinking prior to pregnancy was related to shortened gestation, to lowered birthweight, and to abnormal neonatal behavior (sleep problems, childhood hyperactivity) and mental retardation.

Obstetrical Practices

The use of diagnostic ultrasound in obstetrics is becoming routine: 29.3% of all mothers had at least one ultrasound examination during pregnancy in 1980.

The use of electronic fetal monitoring during labor has increased: 47.2% of all mothers in labor were monitored, according to a 1980 National Natality Survey.

The rate of Caesarean delivery has more than doubled in the past decade to 20.3% of all deliveries in 1983.

Prenatal Care

Neonatal deaths are thought to reflect pre-existing health conditions of the mother and the medical care she and her baby receive during the pregnancy, at the time of delivery and shortly thereafter. Recent declines in neonatal mortality rates are attributed to improved perinatal care and the development of sophisticated technologies for the care of preterm and low birthweight infants.

In 1983, the median number of visits for prenatal care by mothers having any care increased slightly from 11.4 to 11.6. However, the percentage of women who delayed prenatal care to the third trimester or who received no prenatal care increased to 5.6% in 1983, the highest percentage since 1977.

Special Issues

Availability of Care

The increasing risk of law suits and rising costs of malpractice insurance may affect the availability of high-risk obstetrical care. In a 1983 survey by the American College of Obstetricians and Gynecologists, 17.6% of obstetricians responding reported they had decreased their level of high-risk obstetrical care and another 9.1% had ceased practicing obstetrics.

Accessibility of Care

An estimated 25% of women in the prime child bearing age range of 16-24 years (who account for 40% of births) have no medical coverage. An estimated 40% of the uncompensated care given by community hospitals is for maternity care.

Steven Parker

Copyrighted material; do not reprint without permission.

 

View all articles by Steven Parker