Overview of General Problems in Newborns

ByArcangela Lattari Balest, MD, University of Pittsburgh, School of Medicine
Reviewed/Revised Jan 2024
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Problems in newborns may develop

  • Before birth while the fetus is growing

  • During labor and delivery

  • After birth

About 10% of newborns need some special care after birth due to prematurity, problems with the transition from fetal to newborn life, low blood sugar, difficulty breathing, infections, or other abnormalities. Specialized care is often given in a neonatal intensive care unit (NICU).

Gestational Age

Gestational age refers to the number of weeks of pregnancy. Many issues that affect newborns are related to the gestational age because it reflects the newborn's degree of physical maturity at birth.

The gestational age is determined by counting the number of weeks between the first day of the mother's last menstrual period and the day of delivery. This time frame may be adjusted according to other information doctors receive, including the results of early ultrasound scans, which give additional information regarding the gestational age. The estimate of the date a baby will be born (due date) is set at a gestational age of 40 weeks. The due date is an estimate, and only a small number of babies are born on that exact date. Most babies are born within a few weeks before or after the due date.

Newborns are classified by gestational age as

  • Preterm: Delivered before 37 weeks of gestation

  • Full term: Delivered at 37 to before 42 weeks of gestation

  • Postterm: Delivered at 42 weeks or more of gestation

Doctors also use the results of a physical examination and the physical features of the newborn (see sidebar Physical Features of a Premature Newborn) to confirm gestational age.

Problems Before Birth

Problems in a newborn may have begun before birth.

Problems that develop before birth may be related to conditions in the mother that existed before the pregnancy or developed during the pregnancy, or to conditions in the fetus.

Appropriate medical care during pregnancy can help prevent and diagnose many health issues in the mother and fetus. Expectant mothers can improve the chances of having a healthy baby by taking prenatal vitamins, receiving prenatal care throughout pregnancy, and maintaining a healthy diet and weight (see also Self-Care During Pregnancy).

Maternal health problems

If a woman has health issues that begin before or during pregnancy, this can affect the fetus and negatively impact the health of the child. Pregnant people should discuss with their doctor the risks and benefits of different treatments for their specific health conditions.

Diabetes, especially when poorly controlled, may result in an increased risk of birth defects or growth problems in a fetus (an abnormally small baby or large baby). Women with diabetes who are planning to become pregnant or are early in pregnancy should see their doctor regularly for treatment and to ensure that blood sugar (glucose) is well controlled. Newborn babies of mothers with diabetes may have low blood sugar (hypoglycemia), which needs urgent treatment.

Epilepsy (a seizure disorder) increases the risk of birth defects. Some of the increased risk is due to the antiseizure medications that may be necessary to control seizures. However, the mother's seizures can also be dangerous for the fetus. Women who are planning pregnancy or are pregnant should discuss with their doctor the risks and benefits of their current antiseizure medications and whether the medications should be continued, changed, or stopped during pregnancy.

High blood pressure, heart disease, and kidney disease may reduce the growth of the fetus and cause other complications. Women who are planning pregnancy or are pregnant should discuss with their doctor the risks and benefits of their current blood pressure medications and whether the medications should be continued or changed during pregnancy.

High blood pressure is a major feature of preeclampsia, which is a health issue that occurs during pregnancy in some women. It can cause severe problems for the mother and fetus. This disorder can cause the mother's blood pressure to become severely elevated and can affect the mother's kidneys, liver, brain, and other organs. The placenta also may be affected, and the disorder can affect the growth of the fetus or cause the placenta to detach from the wall of the uterus. To prevent or manage such complications, doctors may recommend early delivery. A severe complication of preeclampsia is eclampsia, which is the development of seizures in a woman who has preeclampsia.

Asthma does not usually affect the fetus as long as the mother's symptoms are well controlled. However, some pregnant women have frequent or severe asthma attacks that cause low oxygen levels, which can result in the fetus not getting enough oxygen. In such cases, pregnant women must receive appropriate treatment to protect themselves and the fetus.

Thyroid disease that causes a low thyroid hormone level (hypothyroidism) may cause brain damage in the fetus and lead to long-term neurologic problems if it is not diagnosed soon after birth. Thyroid disease that causes a high thyroid hormone level (hyperthyroidism) may cause the fetus and newborn to have an overactive thyroid gland. In the United States, most states require newborns to be screened for thyroid disease.

Pregnant people who have sickle cell disease may have increased sickle cell crises during pregnancy. If either parent carries the sickle cell gene or is affected by sickle cell disease, there is a risk of sickle cell disease in the child. Testing the parents before pregnancy can determine their risk of having a child with sickle cell disease. Genes that cause sickle cell disease can be detected in the fetus during the pregnancy, but the disease does not start until several months after birth.

Lupus (systemic lupus erythematosus) is an autoimmune disorder. During pregnancy, lupus increases the risk of miscarriage and prematurity and can cause an abnormally slow heart rate in the fetus.

Maternal medication and substance use

Many women worry that taking medications during pregnancy may have negative effects on a developing fetus. However, women who are planning to become pregnant or who are pregnant may need to take certain medications to protect their health or the health of the fetus. Usually, these are medications that are needed to treat an ongoing health issue, such as high blood pressure or diabetes. Pregnant women should ask their doctor before starting any new medication or changing current medications.

Some common prescription medications that can cause problems for the fetus include

Smoking or being exposed to second-hand smoke during pregnancy can decrease the growth of the fetus. Pregnant people should not smoke and should avoid exposure to other sources of tobacco smoke as much as possible.

Alcohol is particularly dangerous to the fetus. Alcohol increases the risk of miscarriage, stillbirth, poor growth of the fetus, prematurity, and birth defects. A particularly devastating effect of alcohol is fetal alcohol syndrome, which causes life-long intellectual, developmental, and behavioral disabilities. There is no safe amount of alcohol during pregnancy.

Opioids, whether prescription medications or illicit drugs (such as heroin, morphine, opium, oxycodone, codeine, hydrocodone, fentanyl, hydromorphone, meperidine, buprenorphine, and methadonetreat

Cocaine increases the risk of poor growth of the fetus and prematurity. The preterm separation of the placenta from the wall of the uterus (placental abruption) is more common among people who use cocaine and can cause stillbirth or oxygen deprivation and brain damage in the fetus. Because cocaine narrows blood vessels, it can cause a stroke or damage other organs in the fetus.

Fetal problems

Birth defects or genetic abnormalities can involve almost any part of the body. Prenatal ultrasonography or fetal genetic testing is used to diagnose many of these defects before birth.

Problems After Birth

Some newborns, especially those who are preterm, have problems that develop or are discovered after birth. Disorders may affect various organ systems in the body.

Some disorders that affect the lungs and breathing include

Some disorders that affect the blood include

Some disorders that affect the hormones include

Some disorders that affect the gastrointestinal tract and liver include

There are health conditions that affect other systems in the newborn's body as well, such as retinopathy of prematurity, which affects the eyes of some preterm newborns.

Diagnosis

  • Before birth, ultrasonography, blood tests, and sometimes imaging tests

  • After birth, various tests

Some problems in newborns may be diagnosed before birth if the mother is receiving regular prenatal care. Other problems are diagnosed after birth.

Diagnosing problems before birth is particularly helpful for fetuses with certain birth defects. Parents can plan with their doctor to deliver an infant in a hospital capable of providing a higher level of newborn care, including having a neonatal intensive care unit (NICU).

Diagnostic tests before birth (prenatal care)

Ultrasonography is used during pregnancy to detect many problems and monitor the growth and development of the fetus. Ultrasonography helps doctors detect abnormalities in the uterus, confirm gestational age, identify if there are twins or triplets (or more fetuses), detect certain birth defects, and determine the sex of the fetus. Knowing the fetus's gestational age helps doctors track fetal growth and know what is normal at each stage of pregnancy. Identifying birth defects helps parents and doctors know what to expect, make plans for the pregnancy, and prepare for problems that could develop after birth. However, ultrasonography is not 100% accurate. Some babies are born with birth defects that were not detected with ultrasonography.

There are several types of screening blood tests that can be done to detect genetic and other abnormalities in the fetus during pregnancy. These are usually done during the first or second trimester. One type of blood test is called cell-free fetal nucleic acid (cfDNA). For the cfDNA test, small fragments of the fetus's DNA, which are present in the pregnant woman's blood in tiny amounts, are analyzed. The test results may be abnormal if the fetus has a genetic abnormality such as Down syndrome (trisomy 21), trisomy 18, or certain other abnormalities.

Other types of blood tests can be done to measure levels of certain hormones and proteins (see First-Trimester Screening and see Second-Trimester Screening). The test results may be abnormal if the fetus has a genetic abnormality, such as Down syndrome (trisomy 21) or trisomy 18, a problem with the formation of the spinal cord called spina bifida, or certain other abnormalities.

Lab Test

If the ultrasound and blood test results indicate a possible problem with the fetus, doctors may do additional tests on cells from the fetus using samples taken with a needle from the amniotic fluid (amniocentesis), placenta (chorionic villus sampling), or the umbilical cord (percutaneous umbilical blood sampling [cordocentesis]). Some parents who are at increased risk of having a baby with genetic abnormalities (based on the results of genetic testing of the parents or based on older maternal age) may decide to have amniocentesis or chorionic villous sampling without first doing screening blood tests.

Fetal echocardiography, a detailed examination of the heart using a specialized ultrasound device, may be done to detect certain heart defects.

Magnetic resonance imaging (MRI) may be used to further evaluate some abnormalities in the fetus that are first detected by ultrasonography. MRI may give additional information about an abnormality and can be useful in evaluating treatment options.

Fetoscopy is an invasive test that is rarely done. For this test, doctors insert a small viewing scope (endoscope) into the womb. Early in pregnancy, the scope may be inserted through the mother's cervix. Later in pregnancy, the scope is inserted through a small incision in the mother's abdomen and then another incision in the uterus. The scope lets doctors take a direct look at the placenta and fetus to identify (and sometimes treat) disorders in the fetus.

Diagnosis after birth

After birth, nurses and doctors do a routine physical examination of the newborn, measure oxygen levels in the blood, and do routine screening tests. Additional tests, including blood tests, x-rays, ultrasonography, and others, may be done if babies have abnormal test results.

Additional testing is needed if the fetus or mother has a known health issue or there was a complication during the birth process.

Depending on gestational age, newborns are classified as preterm, full term, late term, or postterm.

Additional testing may also be needed if the newborn is outside the normal range of weight or size. Newborns are classified into three groups by how much they weigh compared to other newborns of the same gestational age. The three groups are

  • Appropriate for gestational age (AGA): From the 10th to the 90th percentile of weight, meaning they are among the 82 babies in the middle range for weight

  • Small for gestational age (SGA): Less than the 10th percentile of weight, meaning they are among the 9 lowest-weight babies out of 100 born at a particular gestational age

  • Large for gestational age (LGA): Greater than the 90th percentile of weight, meaning they are among the 9 heaviest babies out of 100 born at a particular gestational age

The gestational age and weight classifications help doctors determine the risk of various complications. For example, preterm newborns are at increased risk of breathing problems because their lungs may not be fully developed. Large-for-gestational-age newborns may be at increased risk of low blood sugar (glucose).

Treatment

Medical treatment of specific disorders in newborns is discussed elsewhere.

Many health issues in newborns are minor and resolve on their own or need follow-up care at a doctor's office in the weeks after birth. Some newborns have more severe issues. Newborns (neonates) that are preterm or have serious health issues are cared for in a neonatal intensive care unit (NICU), where this level of care is available.

Neonatal intensive care unit (NICU)

The NICU is a specialized facility that brings together the medical team and technology needed to care for newborns with various disorders. Newborns may need such specialized care because of

The NICU team is usually directed by neonatologists (pediatricians specially trained to manage the problems of newborns). Much of the care is delivered by specialized neonatal nurses. Other team members may include pediatricians, respiratory therapists, social workers, pharmacists, physical and occupational therapists, speech-language pathologists, and other specialized personnel. Many NICUs also have doctors and students in training. Depending on the care required for the newborn, medical and surgical subspecialist physicians are also often involved.

In the NICU, newborns are cared for in incubators or radiant warmers, which keep them warm while allowing staff to observe and treat them. Newborns are usually connected to monitors that continuously measure their heart rate, breathing, blood pressure, and oxygen levels in the blood. They may have catheters placed inside an artery or in the vein running inside the umbilical cord to permit continuous blood pressure monitoring, to allow repeated blood sampling, and to give fluids and medications.

NICU facilities vary widely. Some NICUs have wards in which many babies share a large space, some have modules with a few babies in a space, and some have private rooms for a family and their baby. Regardless of the layout, NICU personnel are focused on meeting the parents’ need for time and privacy to become acquainted with their newborn; to learn the newborn’s personality, likes, and dislikes; and ultimately to learn any special care that they will need to provide at home. Visiting hours vary but are usually flexible so that families can spend as much time with their newborn as they wish. Some hospitals have sleeping facilities for parents on-site or nearby. Many NICUs have cameras, which allows parents to see their baby even when they cannot be present in the NICU.

Sometimes, parents feel that they have little to offer their newborn in a NICU. However, their presence, including physical contact, speaking, and singing to their newborn, is very important. Newborns hear their parents' voices even before birth and are accustomed to them so they often respond better to their own parents’ attempts to calm them. Skin-to-skin contact (also called kangaroo care), in which the newborn is allowed to lie directly on a parent’s chest, is comforting to the newborn and enhances bonding.

Breast milk significantly reduces the risks of necrotizing enterocolitis (a serious intestinal disorder that can occur in preterm infants) and infections in preterm infants, and has a wide range of health benefits for all infants (see Benefits of Breastfeeding). NICU personnel strongly encourage mothers to breastfeed directly or provide breast milk in a bottle when their infant's condition permits. Depending on their gestational age and medical problems, infants in a NICU may not be able to breastfeed or drink breast milk from a bottle, but, in most cases, they can still receive breast milk through a feeding tube that is placed in their nose and goes to their stomach. Preterm infants are not able to suck adequately and are not able to coordinate sucking, swallowing, and breathing. Full-term infants in the NICU may have respiratory problems or other illnesses that make breastfeeding impossible. But, because breast milk is clearly the best food for newborns, mothers are encouraged to pump their breast milk so it can be given to their baby through a feeding tube or saved for later use.

NICU personnel understand that parents need to be kept up to date on their baby's condition and expected course, the care plan, and the estimated time of discharge. Regular discussions with the nurses and medical team are beneficial. Many NICUs also have social workers who help communicate with the parents and assist in arranging family and medical services.

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