What Happens at Birth?

Birth is a dramatic test of transitional physiology. The newborn must rapidly adapt cardiovascular flow and function, establish lung-based oxygenation, develop endocrine control of body metabolism, adapt neurologic responses to new stimuli, and begin to develop an immunologic defense. Unique features seen only during this transitional time can help identify many potential newborn problems. Specific problems are discussed in Chapter 67.

Where Do I Begin the History for a Newborn?

You must obtain the history of the mother, the baby, and the family. Ask about the medical, social, genetic, nutritional, drug, environmental, and infectious history. Review the mother’s obstetric record, the details of labor and delivery, and the immediate postnatal events. Although much information will be in the chart, the interview offers an opportunity to build rapport and trust with the family. Open-ended questions will often bring to the surface both major and minor concerns.

What Should I Ask about the Pregnancy?

Information about previous pregnancies will often indicate potential problems for this pregnancy. Document and confirm outcomes of past pregnancies, especially complications such as prematurity, infection, preeclampsia, or major medical problems. Ask if this pregnancy was assisted with reproductive technology. Ask when prenatal care began and how the due date was determined, especially the results of any screening sonograms. Ask also about mother’s overall health, including blood pressure, and whether screening tests were done for infection and gestational diabetes. Tests for genetic disorders might have included the triple screen for risk of Down syndrome, amniocentesis for chromosome analysis, or other genetic testing based on family history or ethnic background. Ask whether premature labor occurred during this pregnancy and how it was managed. Review the mother’s nutrition, and ask especially if she took a daily folic acid supplement of 0.4 mg starting before conception. Some foods pose infection risks (raw meat, unpasteurized cheese, and cold cuts) while long-lived fish (shark, mackerel, etc.) may contain methyl mercury.

What Infectious Diseases Pose Risks to the Newborn?

Maternal infections may cause fetal or neonatal diseases, many of which can be treated or prevented by immunizations or prophylaxis (Table 14-1). HIV testing is now recommended for all pregnant women. Factors related to the risk of newborn infection include prematurity, prolonged rupture of membranes, maternal fever during labor, and chorioamnionitis. The mother’s group B streptococcus (GBS) status is important: To prevent transmission of GBS from a colonized mother to the newborn, National Institutes of Health (NIH) guidelines recommend that penicillin be administered to the mother at least 4 hours before birth. It is also important to note whether the mother received any other antibiotics during labor and why. For example, antibiotic prophylaxis may be given in labor for mitral valve prolapse.

Table 14-1 Maternal Infections That Can Affect the Newborn

What Maternal Medical Problems Affect the Fetus?

All chronic medical problems, especially cardiac, renal, and pulmonary diseases and the drugs used to treat them, can affect the fetus and newborn. High blood pressure and diabetes during pregnancy can have profound implications for the newborn. Diseases mediated by IgG antibodies, including autoimmune thyroid disorders, myasthenia gravis, lupus, or immune thrombocytopenia, can affect the fetus and newborn. Blood transfusions or previous pregnancies, including spontaneous or elective abortions, could have led to the formation of antibodies against Rh factor, or other blood system antigens. Check the blood types of the mother and newborn because hemolysis and jaundice in the newborn could become a major issue if maternal antibodies to the fetal blood cells are present.

Are Maternal Drug or Toxin Exposures Important?

Ask about use of any prescribed or over-the-counter medication, alcohol, tobacco, and illegal drugs. Alcohol is the most common preventable cause of mental retardation, and there is no known safe amount of alcohol exposure for a fetus. Ask whether the mother had any lead exposure as a child, because lead can be mobilized during pregnancy and transferred to the fetus. Environmental lead in old housing or in the workplace can pose risks to the infant after delivery.

What Is Important in the Family History?

Begin by asking the mother about general issues, such as the ages and health status of grandparents, the baby’s father, and any other children in the family. Ask whether her other children had problems in the newborn period, such as jaundice or infections. Did she breast-feed them? How have they been growing and developing? Are there any concerns about their overall health? The sudden death of a baby in the family may be your only clue to an inborn error of metabolism. Ask about major illness in the family, especially disorders with a known genetic pattern, such as cystic fibrosis, muscular dystrophy, congenital heart disease, cleft lip or palate, developmental dysplasia of the hip (DDH), hemophilia, hemoglobinopathies, and vesicoureteral reflux.

How Does the Social History Help?

The social history provides important information about the family’s ability to care for the newborn, aids discharge planning, and helps plan the follow-up process. Ask whether this was a planned pregnancy and if the mother and father of the child are married, cohabiting, or no longer have a relationship. What do parents do for a living? Does the mother have the financial and health resources necessary to care for herself and her family? What social support system does the mother have? What is the location and condition of the home or apartment? Does the mother or any family member use drugs, alcohol, or tobacco products? Are any firearms present in home? Is there any indication of domestic violence?

What Happened During Labor and Delivery?

Review the labor and delivery records for evidence of fetal distress and risk factors for infection. Gestational age of the fetus and the duration of labor are important for subsequent management. If the fetal heart rate pattern was monitored during labor, did it reflect any signs of distress? If the fetus showed signs of stress, what were the results of additional testing such as a fetal scalp pH? Fetal distress might prompt emergency cesarean section, or the infant might be delivered with forceps or vacuum suction. The presence of meconium in the amniotic fluid may indicate fetal distress, as would a low Apgar score and need for resuscitation at birth.

Does the Amniotic Fluid Predict Problems?

Prenatal sonograms can identify the amount of amniotic fluid. Polyhydramnios suggests an upper gastrointestinal (GI) obstruction in the fetus. Severe oligohydramnios raises the possibility of renal abnormalities. The medical record will indicate whether meconium was present in the amniotic fluid and if special treatment was administered to the infant. Meconium-stained fluid occurs in up to 10% of term deliveries, but most infants require no intervention. A depressed newborn with meconium-stained amniotic fluid will require evaluation of the airway and possible intubation at birth.

What Is the Apgar Score?

The Apgar score assesses heart rate, respiratory rate, skin color, muscle tone, and response to stimuli at 1 minute and 5 minutes after birth, a physiologically dynamic time when the newborn must make the transition from fetal to extrauterine life (Table 14-2). Each component of the Apgar score may receive 0, 1, or 2 points. A perfectly healthy baby would have an Apgar score of 10.

Table 14-2 Apgar Scores

What Transitional Issues Must I Consider?

What Is Important in the Newborn’s Medical History?

The baby’s history after the transition period will help in determining whether this is truly a healthy newborn. Infants lose up to 10% of birth weight in the first days of life, so you must monitor for excessive weight loss. Most infants urinate and excrete meconium stool by 24 hours; if this has not occurred, you should consider the possibility of urinary tract or bowel obstruction. The initiation of feeding is crucial to monitor: How well does the infant feed, how much, and how often? If breast-feeding, is the baby latching on to the breast? Is the baby vomiting or spitting up after feeding? After the transition period, did the baby demonstrate any signs of respiratory distress, cyanosis, jaundice, temperature instability, or any unusual behaviors or neurologic findings?

What Tests Are Performed for Newborn Infants?

Most healthy newborns need few laboratory tests beyond blood glucose shortly after birth and the neonatal screen after 24 hours of age. If the baby had a screening blood glucose test, what was the result? There is still debate about the normal glucose level for a newborn, but any value below 40 mg/dl is reason for concern and intervention. Complete blood count, total and direct bilirubin levels, and serum electrolytes may be done when conditions justify. If the blood type, Coombs’ test, and rapid plasma reagin (RPR) status have been assessed, they should be noted. Cultures may be done if suspicion of infection exists.