Problems in newborns may develop
About 10% of newborns need 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 refers to how far along the fetus is. 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 the number of weeks between the first day of the mother's last menstrual period and the day of delivery. This time frame is often adjusted according to other information doctors receive, including the results of early ultrasound scans, which give additional information regarding the gestational age. Babies are estimated to be due (the due date) at a gestational age of 40 weeks.
Newborns are classified by gestational age as
Premature: Delivered before 37 weeks of gestation
Full term: Delivered at 37 to before 41 weeks of gestation
Late term: Delivered at 41 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 Physical Features of a Premature Newborn) to confirm gestational age.
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 problems in the fetus.
The mother's health problems during pregnancy can affect the growing fetus and negatively impact the health of the newborn. Although mothers rightly worry about the effects of medications on a developing fetus, they also must realize that failing to take necessary treatments can allow their medical disorders to harm the fetus. Women should discuss with their doctor the risks and benefits of different treatments for their specific conditions.
Asthma does not usually affect the fetus as long as the mother's condition is well controlled. However, some women have significant problems with their asthma during pregnancy and must take appropriate treatment to protect the fetus.
Cancer itself does not usually affect the fetus, but drugs used to treat cancer may have side effects that may affect the fetus.
Epilepsy (a seizure disorder) increases the risk of birth defects. Some of the increased risk is due to the anticonvulsant drugs that may be necessary to control seizures. However, the mother's seizures also are dangerous for the fetus. Women should discuss with their doctor the risks and benefits of drug treatment before they stop taking their anticonvulsants.
High blood pressure, heart disease, and kidney disease may reduce the growth of the fetus and cause other complications.
Preeclampsia can cause severe problems for the mother and fetus. The disease 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 too is affected, and the disease can affect the nutrition 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.
Women who have sickle cell disease may have increased sickle cell crises during pregnancy. If the father carries the sickle cell gene or is affected by sickle cell disease, there is a risk of sickle cell disease in the offspring. Testing of 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.
Thyroid disease that causes a low thyroid hormone level (hypothyroidism) may cause brain damage in the fetus and lead to long-term neurologic problems. Thyroid disease with a high thyroid hormone level (hyperthyroidism) may cause the fetus and newborn to have an overactive thyroid gland.
Most prescription drugs are safe during pregnancy, but women should review all their drugs with their doctor when they become pregnant or plan to become pregnant. However, even prescription drugs that cause some risk may still be necessary for women. Uncontrolled medical problems in the mother also can be dangerous to the fetus. Some common prescription drugs that can cause problems for the fetus include
Alcohol is particularly dangerous to the fetus because it is a teratogen (a substance that can cause birth defects). 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.
Opioid drugs, such as heroin, morphine, opium, oxycodone (OxyContin®), codeine, hydrocodone, fentanyl, hydromorphone (Dilaudid®), meperidine (Demerol®), buprenorphine, and methadone, affect the growth of the fetus and can cause withdrawal symptoms in the newborn beginning hours to several days after birth. These and other opioids, particularly those combined with other drugs such as acetaminophen, are prescribed under many different brand names (some of which in the United States include Lorcet®, Lortab®, Norco®, Vicodin®, Percocet®, Endocet®, Roxicet®, and Tylenol®#3). Mothers should be aware of the ingredients of any painkiller they take. Opioid drugs such as methadone and buprenorphine that are sometimes used to treat a mother's opioid dependence also can cause withdrawal symptoms in newborns. Newborns withdrawing from methadone may need longer treatment than newborns withdrawing from other opioids.
Cocaine increases the risk of poor growth of the fetus and prematurity. The premature separation of the placenta from the wall of the uterus (placental abruption) is more common among cocaine users 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. Although cocaine was once widely thought to cause permanent brain injury, long-term studies have not shown that it causes significant long-term intellectual and developmental disabilities.
Some newborns, especially those who are premature, 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 diseases that affect other systems in the newborn's body as well, such as retinopathy of prematurity, which affects the eyes of some premature newborns.
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. Mothers and their doctor can then plan to deliver such infants in a hospital capable of providing a higher level of newborn care, including having a neonatal intensive care unit (NICU).
Ultrasonography is used before birth to detect many problems and monitor the growth and development of the fetus. Ultrasonography helps doctors determine the sex of the fetus, detect abnormalities in the uterus, detect certain birth defects, and determine the fetus's gestational age. Knowing the fetus's gestational age and birth defects helps doctors anticipate problems that could develop at birth. However, ultrasonography is not 100% accurate. Some babies are born with birth defects that were not detected with ultrasonography.
A triple screen or quad screen is a test done on the mother's blood to measure levels of certain hormones and a protein called alpha-fetoprotein. The test results may be abnormal if the fetus has a genetic abnormality such as Down syndrome (trisomy 21), trisomy 18, spina bifida, or certain other abnormalities. The blood test is done in the first trimester and is often combined with ultrasonography to measure the thickness of the skin folds of the neck of the fetus. Some of the blood tests may be repeated in the second trimester, and this combination of tests is referred to as a sequential screen.
If the results of the screening tests indicate a high risk of abnormalities in the fetus, the mother is offered further testing, most commonly noninvasive prenatal testing (NIPT). NIPT involves genetic testing of the small amounts of fetal DNA that leak from the fetus's circulation into the mother's blood. In some cases, doctors do 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 (cordocentesis).
Increasingly, NIPT combined with a single blood test of the alpha-fetoprotein level is replacing the triple, quad, and sequential screens. This approach to testing has increased accuracy at an overall lower cost.
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) is now being 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 in which 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.
After birth, nurses and doctors do a routine physical examination, measure oxygen levels in the blood, and do routine screening tests. Additional tests, including blood tests, x-rays, ultrasonography, and others, may be done when babies have specific problems or have abnormal findings on the routine tests.
Newborns are further classified into three groups by how much they weigh compared to other newborns of the same gestational age. The three groups are
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
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
The gestational age and weight classifications help doctors determine the risk of various complications. For example, premature and late preterm newborns are at increased risk of breathing problems because their lungs may not be fully developed. Large-for-gestational-age newborns may have more difficult births and be at increased risk of low blood sugar (glucose).
Medical treatment of specific disorders is discussed elsewhere. When possible, the sickest newborns (neonates) are cared for in a neonatal intensive care unit (NICU).
The NICU is a specialized facility that brings together the medical team and technology needed to care for newborns (neonates) with various disorders. Newborns may need such specialized care because of
The NICU team is typically 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, neonatal nurse practitioners (advanced-degree nurses specifically trained to manage newborns), neonatal physician assistants, 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 by the baby, 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. Babies 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 drugs.
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.
Sometimes, parents feel that they have little to offer their newborn in a NICU. However, their presence, including stroking, 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 the mother’s or father’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 premature infants) and infections in premature infants, and has a wide range of health benefits for all infants (see Benefits of Breastfeeding). NICU personnel strongly encourage mothers to breastfeed when their infant's condition permits. However, 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. Premature 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 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.