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Health of Infants and Children
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Health and Development of Children Younger than Age 2

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Erythromycin and Pyloric Stenosis

A study published in the July 2002 issue of the Archives of Pediatrics and Adolescent Medicine confirms suspicions that a common antibiotic can cause a serious condition in very young infants.

Infantile hypertrophic pyloric stenosis (IHPS) occurs when the muscle surrounding the outlet from the stomach becomes overgrown and obstructs the passage of food into the intestines. The condition, which usually arises in the first three to five weeks of life, causes projectile vomiting. This can lead to dehydration, weight loss, and electrolyte imbalances that affect kidney function. Physicians have long believed that exposure to the antibiotic erythromycin is related to the condition.

To investigate the link, researchers tracked the antibiotic use and IHPS occurrence in over 314,000 infants between 1985 and 1997. Of the 7,138 infants given prescriptions for erythromycin within the first 90 days of life, 804 were diagnosed with pyloric stenosis. Further analysis showed that while infants younger than two weeks old were rarely given erythromycin, those who were exposed within the first two weeks of life were eight times as likely to develop IHPS as an infant who had not received the drug during this time. Babies who received erythromycin after the first two weeks did not appear to have an increased risk for the condition.

Physicians commonly use erythromycin to treat infants with illnesses such as respiratory and ear infections, whooping cough, and conjunctivitis. The results of this study suggest the risks and benefits of erythromycin need to be carefully weighed — and perhaps other antibiotics tried — before it is prescribed for use in infants younger than two weeks.

October 2002 Update

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Immunizations for 2002

Vaccinations against childhood illnesses are arguably one of the most significant medical achievements of the twentieth century. One hundred years ago, approximately half of all children born in the United States died before the age of 5, many of them from diseases that today can be prevented by vaccines. With proper immunization, the number of cases of these diseases has been reduced dramatically.

Although no new vaccines have been added to the 2002 recommended childhood immunization schedule, this year's schedule highlights vaccines for pre-adolescents and "catch-up" vaccines for children who have fallen behind the currently recommended schedule.

In addition, due to unusual national shortages of the pneumococcal and diphtheria/tetanus/pertussis vaccines, the 2002 immunization schedule also includes a link to information from the Centers for Disease Control (CDC), which explains the necessary modifications to the recommended schedule for these vaccines. These vaccine shortages will hopefully only be temporary.

Please discuss your child's immunization history with the doctor to insure that his or her immunizations are up to date in accordance with the current 2002 Recommended Childhood Immunization Schedule, approved annually by the CDC, the American Academy of Pediatrics, and the American Academy of Family Physicians. For additional reliable and up-to-date information about vaccines and their importance, visit the National Immunization Program website at or the American Academy of Pediatrics website at
April 2002 Update

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New Information on Sudden Infant Death Syndrome

Sudden Infant Death Syndrome (SIDS) is the most common cause of death in infants from one to six months of age, peaking between ages two and four months. For a number of years, pediatricians have recommended putting babies to sleep on their backs to prevent SIDS, and studies have proven that this position reduces babies' risk. The "Back to Sleep" campaign has led to changes in infant sleep position — specifically, a decrease in the amount of prone (on the tummy) sleeping and, subsequently, a statistically significant decrease in the incidence of SIDS. Unfortunately, doctors still don't know for sure what causes SIDS and how best to prevent it entirely.

A new study from the University of Washington, published in the December 2001 Journal of Pediatrics, has found additional risk factors for SIDS. Researchers found the risk of SIDS was increased for infants weighing less than 5 ½ pounds, infants born to mothers who smoked, infants born to unmarried mothers, black infants, and infants who received limited prenatal care.

While research on the causes of SIDS continues, these findings can help doctors advise parents about reducing their baby's risk. Similarly, this information should help doctors increase public awareness about the importance of prenatal care.

If you have an infant at home, do all that you can to prevent SIDS.

  • Put your baby on his or her back to sleep.
  • Use a firm, snug-fitting mattress, and a crib that meets federal safety standards.
  • Do not put soft bedding (pillows, comforters, sheepskins, and bumpers) or stuffed animals in your baby's crib.
  • Dress your baby and adjust the room temperature so that he or she is warm, but not hot.
  • Never smoke around your baby (or during pregnancy).

March 2002 Update

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Young Children Need Seat Restraints on Flights, too.

Although child safety seats are mandatory for all children less than 40 pounds riding in automobiles, there are no such laws for children riding in airplanes. Children younger than 2 years of age are not required to be strapped in for take off or landing on commercial aircrafts. Indeed, they are most likely to be found being held by a parent on their lap.

The American Academy of Pediatrics (AAP) has recently published recommendations encouraging regulations requiring all passengers to be properly restrained during flights. Similar to Child Safety Seat laws for automobile passengers, the AAP recommends infants less than one year old or less than 20 pounds ride in rear facing seats properly installed in an airline seat. A forward-facing seat should be used for children at least one year old and weighing 20 to 40 pounds. Safety seats should not exceed 16 inches in width to fit into commercial aircraft seats. Children weighing more than 40 pounds can be secured safely using a seat belt in a traditional manner used by older children and adults.

While parents may be tempted to hold an infant on their lap rather than to purchase a separate seat, these new regulations encourage safety over expense. Passengers can always ask if discounted seats for infants and children are available for their destination and flight.
January 2002 Update

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Home Monitors and SIDS

Sudden Infant Death Syndrome devastates some 3,000 families each year in the United States. To prevent such tragedies, many babies are sent home with expensive monitors. But a new study, the Collaborative Home Infant Monitoring Evaluation (CHIME), suggests the cardiorespiratory events these machine track are common and may not necessarily be signs of impending SIDS.

Although researchers aren't certain what causes SIDS, some think prolonged apnea (periodic cessation of breathing) and bradycardia (slower heart rate) may precede the fatal event. So it's become customary for parents to use home monitors with the hope they'd be alerted of such problems before it's too late. The devices are traditionally recommended for preterm infants (£ 34 weeks gestation), siblings of SIDS, and for infants who've previously experienced an apparent life-threatening event requiring mouth-to-mouth resuscitation. To investigate whether these infants are actually at an increased risk for apnea and bradycardia, CHIME monitored 1,079 children during their first 6months.

During the 718,358 hours of home monitoring, no deaths occurred, but at least one bout of apnea and/or bradycardia occurred in 41% of the children, including healthy full-term babies. Only preterm infants were at an increased risk of extreme events that lasted longer than conventional alarm standards. But this added risk vanished before they reached the age when SIDS is most common.

The results suggest these cardiorespiratory events are common and aren't immediate precursors to SIDS. The researchers also noted that conventional devices might have missed many of the events recorded using the highly sensitive monitors used in the study. While the effectiveness of home monitors remains unproven for preventing SIDS, there's no doubt they can provide the peace of mind many parents need. But the best advice to avoid putting infants to sleep on their stomachs, using soft bedding, and exposing them to cigarette smoke.
August 2001 Update

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Early Childcare and Communicable Illnesses

All kids get sick, but young children in day care are at increased risk for infection.

The National Institute of Child Health and Human Development recently examined rates of ear infections, gastrointestinal tract illnesses, and upper respiratory tract infections in children participating in the Institute's Study of Early Child Care. The study is following 1200 children from birth to age three in ten locations across the county. The researchers found the rates for each illness were higher for children in day care than for those reared exclusively at home during the first two years of life. But this difference disappeared by the time they were three years old.

The number of hours per week children spent in day care generally had little to do with their likelihood of getting sick. Instead, the great the number of children enrolled in a facility, the greater a child's risk of illness. But being sick more frequently didn't have developmental consequences. Some parents felt that sickly children had increased behavioral problems, but this was likely the result of increased stress.
July 2001 Update

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Study Shows Fish Consumption Protects Against Stroke, But FDA Suggests Pregnant Women Should Take Caution

A large study in the Journal of the American Medical Association (JAMA) recently showed that regularly eating fish might protect against ischemic stroke, which is the most common type of stroke. Numerous studies have already shown an association between fish consumption and a reduced risk of heart disease. But there is a caveat. The Food and Drug Administration (FDA) recently warned that pregnant women and women who are of childbearing age who may become pregnant, should avoid certain types of fish that contain high levels of mercury, which may be harmful to their unborn children.

Results of the Nurses' Health Study, published in the JAMA article, involved nearly 80,000 women. It showed that women who ate fish two to four times a week had a 48% lower risk of ischemic stroke — the kind caused by blood clots — than women who ate fish less than once per month. Even women who ate fish only once a week or less had a risk reduction, but it was not statistically significant. These results held true primarily among women who did not regularly take aspirin, which prevents the formation of blood clots. Omega-3 fatty acids, the protective substances found in fish, reduce levels of fats related to cardiovascular disease and help prevent blood clotting. Dark, oily fish such as mackerel, salmon, and sardines are a good source of omega-3 fatty acids.

Although pregnant women need not give up fish — and its beneficial health effects — altogether, they should be careful about what types of fish they eat. The FDA has advised that pregnant women and those who may become pregnant stop eating shark, swordfish, king mackerel, and tilefish. These large, long-living fish contain hazardous levels of methyl mercury, a form of mercury that can accumulate in a woman's body and affect the developing central nervous system of an unborn child. This can lead to babies with slower cognitive development. As an extra precaution, the FDA advised that nursing mothers and young children also avoid these fish. Mercury gets into both fresh and salt water through industrial pollution.

Some critics feel the FDA's mercury warnings are not strong enough. A report by the National Academy of Sciences suggested the exposure limits for mercury should be four times stricter.

While this controversy remains unresolved, the FDA encouraged pregnant women to continue to eat a variety of other fish, containing very low levels of mercury, as part of a balanced diet. Among other health benefits, the fatty acids in fish enhance brain development. According to the FDA, women can safely eat up to 12 ounces of fish per week. Fish that contain low levels of mercury include shellfish, canned fish, smaller ocean fish, and farm-raised fish. Women who eat fish caught by family or friends should contact their local health department for advice on the safety of fish from local waters.
May 2001 Update

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Good News for Breast-Fed Babies

Breast-feeding has been linked to many advantages, including fewer earaches, colds, and asthma attacks. Now, a large trial involving almost 16,500 mother-infant pairs has shown even more benefits of breast-feeding. The study demonstrated that long-term, exclusive breast-feeding significantly decreases the risk of gastrointestinal tract infections and atopic eczema during a child’s first year of life.

Published in the Journal of the American Medical Association, the study involved mothers from the former Soviet republic of Belarus. To avoid a conflict of interest, given the advantages of breast-feeding that are already established, the program studied mothers who breast fed for a long time compared to mothers who breast fed for a short time then switched to bottle feeding. Some hospitals were randomly chosen to promote breast-feeding, through programs involving counseling from doctors and midwives; other hospitals, which served as a control group, provided the usual obstetric care. After 12 months, nearly 20% of the infants who were part of the breast-feeding program were still nursing, compared to 11.4% of the control group.

In the first year, only 9% of the infants in the breast-feeding program had one or more gastrointestinal infection compared to about 13% of the control group. In addition, 3% of the breast-fed infants developed atopic eczema (a scaly, allergy-associated skin irritation), compared with 6% of the other babies.

The World Health Organization recommends only breast milk for the first four to six months, and recommends that breast-feeding (in combination with formula) continue until 2 years of age. The American Academy of Pediatrics recommends breast milk alone until 6 months, and breast-feeding plus formula until 12 months old. This study suggests that breast-feeding exclusively for the first year could provide greater health benefits to the child.
February 2001 Update

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Age-Appropriate Safety Seats for Young Children Can Significantly Reduce Risk for Serious Injury

Studies have shown that when it comes to child car safety, any restraint is better than none. But new research illustrates, for the first time, that choosing the appropriate restraining device — child safety seats for children under age 4 and booster seats for children ages 4 and older rather than seat belts — can significantly further reduce your child's risk of injury.

Researchers from The Children's Hospital of Philadelphia and the University of Pennsylvania School of Medicine studied insurance reports of car crashes involving children ages 2 through 5, then followed up with telephone interviews of the driver of the accident vehicle and the parents of the children involved in the crash. The investigators found that, compared to children in child safety seats or booster seats, children wearing seat belts at the time of the crash were 3.5 times more likely to suffer a significant injury. Significant injuries were defined to include internal organ injuries and most fractures, among other things. In addition, children wearing seat belts were 4.2 times more likely to have a significant head injury, such as a concussion or more severe brain injury, than children wearing age-appropriate restraints.

You can use the following criteria to improve your child's safety. Children who are at least one year old and weigh more than 20 pounds should be placed in a forward-facing child safety seat in the rear of the vehicle. Children who are at least 4 years old and weigh 40 pounds or more should ride in a belt-positioning booster seat that uses the vehicle's lap and shoulder belts. Your child is ready to use the vehicle's lap and shoulder belts when the lap belt rests low and snug across the hips and the shoulder belt doesn't cross the face or the neck.

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Tobacco Smoke Can Trigger Childhood Asthma

A new study further highlights the need to eliminate children's exposure to tobacco smoke. After evaluating a random sampling of about 40,000 children between the ages 6 and 7 and 13 and 14, researchers in Italy determined exposure to the secondhand smoke of at least one parent increased a child's relative risk of asthma.

The children's parents were surveyed about their smoking habits and the respiratory health of their children. Children in both age groups who were exposed to secondhand smoke from both parents were more likely to have asthma. Having a mother who smokes was a slightly stronger predictor than having a father who smokes.

These results bolster previous research that has linked exposure to secondhand smoke in the home to childhood asthma. Restricting smoking to outside the home doesn't seem to help either. A 1997 study in California found that even if their parents smoked outside, children hospitalized for acute asthma took longer to recover when discharged than children whose parents did not smoke. Tobacco smoke clings to hair and clothes fibers, so even if the activity itself takes place away from child, the child can still be exposed to secondhand smoke.

For more information about asthma, see page 505 of the Family Health Guide. For tips on how to quit smoking, see page 57.

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Less Painful Newborn Circumcision

Each year, millions of newborn males undergo circumcision. Their facial expressions and crying indicate that circumcision causes immense pain, yet many physicians do not administer anesthesia or pain medication for this procedure. In part, this is because many doctors are unfamiliar with the use of such medications in infants and are concerned about possible side effects.

A number of interventions can help reduce the pain of circumcision. Dorsal penile nerve block (DPNB), lidocaine-prilocaine cream (a mixture of local anesthetics), sucrose, and acetaminophen are each individually safe and effective but do not completely eliminate pain in all infants. Another approach is to use the Mogen clamp, which is associated with less pain than the Gomco clamp.

In an effort to minimize the pain of circumcision, researchers conducted a study on 86 infant males to assess the efficacy and safety of a combination of interventions. Fifty-seven infants were circumcised using the Mogen clamp and a combination of analgesics that included acetaminophen, lidocaine-prilocaine cream placed on the penis, gauze embedded with sugar and dipped in grape juice placed in the mouth, and an injection of DPNB. Researchers videotaped the infants during the procedure and assessed pain by analyzing facial activity and the percentage of time spent crying. The researchers compared the results with data from a previous study in which 29 infants were circumcised using the Gomco clamp and lidocaine-prilocaine cream.

Results from this study suggest that circumcision with the Mogen clamp took less time than circumcision with the Gomco clamp did (mean time of 55 seconds compared to 9 minutes, 37 seconds). Infants in the combination group had less facial activity indicating pain and cried for a smaller percentage of time than the infants in the single intervention group did. Furthermore, 46% of the infants in the combination group did not cry at all during the procedure and 12% cried less than 10% of the time. Infants in the combination group did not experience any adverse effects. Facial activity and crying was not eliminated in all infants treated with the combination of interventions, yet researchers do not know if these responses were due to the pain of the procedure or the discomfort of restraint. This study demonstrates that circumcision with the Mogen clamp and combined analgesia is safe, takes less time, and substantially minimizes pain. Parents of male infants and the physicians performing circumcisions should consider this approach.

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Fighting Sudden Infant Death Syndrome

By most accounts, the “Back to Sleep” campaign, which urges parents to place infants on their back in order to decrease the incidence of Sudden Infant Death Syndrome (SIDS), has been a success since its inception in 1994. The percentage of babies most at risk for SIDS (infants aged 8 to 15 weeks) who were placed on their backs to sleep tripled between 1994 and 1998. In addition, the SIDS rate in the United States dropped by 38% between 1992 (when the American Academy of Pediatrics (AAP) recommended that infants not be put to sleep on their stomachs) and 1996. However, the campaign’s ambitious goal of an over 90% compliance rate has not been met. Thus, the campaign continues.

The concerns of parents may act as an obstacle to their placing their infant on his or her back. These concerns, for the most part, are rooted in unfounded fear. Many parents cite a fear that their infant will choke as the reason that they do not place their infant on his or her back. This fear is unfounded, according to researchers who conducted a study that observed no increased risk of choking in infants aged 4 to 6 weeks and in infants aged 6 to 8 months who were placed on their backs compared with infants who were placed on their stomachs.

Placing infants on their backs significantly reduces their risk for sudden death. Parents can further reduce this risk by doing the following, in addition to placing their infant on his or her back:

  • If you are pregnant now, be sure to get good prenatal care. Eat well, don’t smoke, and avoid alcohol. These measures help your baby get a healthy start and reduce the chances your baby will be born early or at a low birthweight (both of which can increase SIDS risk).
  • Once the baby is born, keep him or her in a smoke-free environment.
  • Have the baby sleep on a firm mattress or other firm surface.
  • Avoid putting fluffy blankets or coverings — as well as pillows, sheepskins, blankets, or comforters — beneath the baby. Infants should not sleep on a waterbed or with soft stuffed toys.
  • Keep the baby warm enough, but do not allow infants to become overheated.
  • Seek proper medical advice promptly if the baby is unwell.

The following Websites offer additional information:

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