Which newborn assessment finding would be the most concerning?

INTRODUCTION

Conducting a thorough neonatal assessment is necessary to ensure that the newborn transitions appropriately to extra-uterine life [1]. Skilled observation should begin at the time of birth and continue frequently during the first 24 hours. Nurses should be aware of the normal features of the transition period in order to detect disorders in adaptation soon after birth [2]. The newborn assessment provides much needed information concerning the state of health of the transitioning newborn as well as a basis with which to formulate further care.

Every infant presents uniquely and has certain individual needs. While the vast majority of infants transition without problems, some present with anatomical, physiologic, infectious, and developmental issues that should be addressed. The assessment of the newborn should begin with obtaining a health history and include the initial Apgar assessment, transitional assessment during the periods of reactivity, assessment of gestational age, and a physical examination. This systematic approach ensures a thorough exam.

Nurses in many different areas of nursing conduct newborn assessments. The information provided in this course includes warning signs, which require immediate attention, as well as basic, normal assessment findings in the newborn. Due to the large volume of information, this course primarily covers the first 24 hours of life.

PRENATAL HISTORY

A prenatal history is imperative to the comprehensive care of each newborn and should cover the maternal sequelae, family history, and fetal care history [3]. Maternal history consists of information concerning past pregnancies, including complications, and specifics of labor and maternal illness, including infections and the use of alcohol or drugs [3]. It should also elicit information regarding the current pregnancy, such as the quality and quantity of prenatal care, current laboratory values [including blood type and Rh factor and the results of standard group B streptococcus screening], and the presence of any significant risk factors to the fetus. Obtaining a family history involves inquiring regarding past illnesses, genetic issues, and physiologic problems of parents and siblings [3]. The neonatal history encompasses factors such as vital signs, Apgar scores, required stabilization interventions, and the newborn's general appearance and reaction to the environment [3].

RISK FACTORS

An understanding of the maternal/fetal risk factors is important for the anticipation of possible problems that the infant may experience. Risk factors may be divided into two categories: those that can be modified, such as smoking and drug use, and those that are inherent, such as diabetes and pre-eclampsia.

Smoking

Smoking during pregnancy continues to be an alarmingly common problem. It has been associated with an increased incidence of ectopic pregnancy, preterm birth, low birth weight infants, placental abruption, premature rupture of membranes, and sudden infant death syndrome [SIDS] [4,5,6]. Studies have shown that low birth weight can be attributed to maternal smoking in 20% to 30% of cases [1]. Smoking causes vasoconstriction, resulting in decreased uterine perfusion and decreased oxygen-carrying capacity for the fetus [4,7]. Smoking has also been implicated in poor fetal nutrition, as it interferes with the ability of the fetus to metabolize key vitamins and minerals [4]. Cigarettes contain nicotine, which is a highly addictive substance. Infants of smokers tend to be fussier than those of nonsmokers, and it is thought that they experience nicotine withdrawal symptoms, especially if they are bottle-fed [6].

Drug Use

Illicit drug use can lead to a multitude of problems for the developing fetus. Cocaine, for example, affects all of the user's body systems, including the cardiovascular system, which can lead to heart attack and stroke. It may cause liver disease and perforation of the nasal septum [4]. It is highly addictive. The effect of cocaine on the fetus is directly related to the effect on the mother, including increased blood pressure, which leads to decreased uterine blood flow and perfusion [1]. These effects may lead to preterm labor, low birth weight and length infants, a decreased head circumference, placental abruption, and stillbirth. Additional effects of prenatal cocaine exposure include cerebral infarcts, renal defects, necrotizing enterocolitis [NEC], cardiac anomalies, and mild facial dysmorphic features [1].

Opioid use during pregnancy can be equally devastating. Maternal signs of opioid use include constricted pupils, slurred speech, euphoria, and respiratory depression [4]. Possible effects on the fetus include meconium aspiration, spontaneous abortion, and low birth weight, which may lead to future developmental problems [8,9]. Infants who are born physically dependent on opioids experience intense acute and subacute withdrawal symptoms [8,9,10].

Studies regarding the effect of cannabis use during pregnancy have shown inconsistent results [2,11]. It is thought that smoking cannabis has similar dangers as smoking cigarettes, including increased carbon monoxide levels, which lead to decreased oxygen levels and fetal hypoxia. Some studies have shown that women who smoke cannabis regularly during pregnancy are more likely to give birth to an infant with fetal alcohol syndrome-like characteristics [2]. Other studies have shown that prenatal exposure to cannabis is directly associated with lower birth weight, reduced birth length, and a smaller head circumference [11,186]. Cannabis readily crosses into breast milk, and women that smoke cannabis should be advised against breastfeeding [2].

Diabetes

Gestational diabetes affects up to 9.2% of all pregnancies [12,13]. Factors that place women at higher risk for developing gestational diabetes include age of 25 years or older, obesity, and a family history of type 2 diabetes [4,14]. The infant of a mother with diabetes, regardless of whether the cause is gestational diabetes or pre-existing disease, is affected in a multitude of ways. The effects are more pronounced in "brittle" cases. Fetuses that are continuously exposed to high blood glucose levels will produce more insulin in response, leading to excessive fetal growth and infants who are large for gestational age [i.e., macrosomia] [1,14]. This in turn can place them at higher risk for birth trauma and shoulder dystocia [4]. In the neonatal period, infants of mothers with diabetes are also more likely to experience hypoglycemia that results from the precipitous drop in available blood sugar while they continue to produce excessive amounts of insulin. This can lead to serious neurologic damage with complications including developmental delay, heart failure, and seizures [13,14,15]. Infants of mothers with diabetes are also at higher risk for neonatal jaundice, and women with diabetes are at higher risk for developing pre-eclampsia [4,14]. These infants are also more likely to be obese and develop type 2 diabetes as adults [13].

Pre-eclampsia

Pre-eclampsia is a form of pregnancy-induced hypertension that begins after 20 weeks' gestation. The diagnosis is based on the presence of new-onset hypertension [after 20 weeks' gestation] and at least one of the following: proteinuria; thrombocytopenia; kidney or liver function changes; pulmonary edema; or new-onset, severe, unrelenting headache. Accompanying signs may include headache, visual disturbances, and epigastric pain. Management of pre-eclampsia includes blood pressure control, bed rest, and fluid restriction. The only cure is delivery. The fetus is affected as a result of the hypertension leading to decreased uterine perfusion; chronic hypoxia can result. Infants of women with pre-eclampsia are at higher risk for low birth weight and the catastrophic event of placental abruption [4,16]. Untreated pre-eclampsia may result in eclampsia, which includes the development of seizures. The infant of a woman with eclampsia is at risk for effects of placental abruption, preterm birth, and acute hypoxia [4,16].

Group B Streptococcus

Group B streptococcus [GBS] is a leading cause of early-onset neonatal sepsis causing death to newborns [17,18]. Group B streptococcus is found in the mother's genital tract and rectal area [19]. Colonization is common and generally causes no symptoms in the healthy mother. In its 2010 guidelines, the Centers for Disease Control and Prevention [CDC] recommended universal rectovaginal screening of all pregnant women between 35 to 37 weeks' gestation, with subsequent intrapartum antibiotic prophylaxis; however, in 2019, the American Society for Microbiology [ASM] assumed responsibility for maintaining and updating these guidelines [17,18,143]. The ASM currently recommends screening between 36 weeks to 37 weeks/6days [143]. Universal screening has helped decrease the incidence of early-onset neonatal GBS; however, the incidence of late-onset neonatal GBS has not decreased [17,18,143]. Infants generally become infected during labor and birth due to vertical transmission of the bacteria after the membranes have ruptured; therefore, sepsis is a more likely outcome with delayed delivery after rupture of the membranes. Occasionally, fetuses may become infected during pregnancy.

As noted, there are two different types of GBS infection: early- and late-onset. Early-onset GBS occurs in the first seven days of life and may be detectable in the first six hours [19,20]. It can make a seemingly healthy newborn become ill very quickly. The most common symptoms of early-onset GBS are pneumonia, meningitis, respiratory distress, and sepsis [19,21]. Early-onset GBS has a higher fatality rate than late-onset GBS. Late-onset GBS may not be detected for up to three months and is believed to be transmitted either during birth, through breast milk, or in a nosocomial form [19,21,22]. The most common symptoms are sepsis and meningitis.

GBS sepsis should be considered whenever a newborn demonstrates respiratory distress, temperature instability, or poor feeding. Laboratory values that may be assessed when there is suspicion of GBS include complete blood count with differential, blood culture, chest x-ray, urine culture and analysis, stool culture, and possible lumbar puncture [23]. Treatment of GBS-infected newborns includes IV antibiotics [24].

PLACENTAL EXAMINATION

A thorough assessment of the placenta at the time of delivery may assist with age determination and present significant diagnostic information [3]. The placenta should be assessed for size, color, odor, and the presence and number of membranes [3,25].

The ratio of fresh placental weight to infant weight is normally 1:6 in the last trimester. Very large placentas may be indicative of diabetes; very small placentas may be indicative of chronic hypoxia, perhaps caused by hypertension. The placenta should have a uniform thickness throughout; depressions may be from abruption or infarction [3,25,26].

Color may give an estimate of gestational age, as the placenta will become duller with more calcium deposits postdate. Pallor or plethora should be noted as they may indicate fetal blood volume inadequacy or excess and/or hemoglobin status. Staining by meconium or blood through the membranes or of the cord indicates an insult of longer duration. Vernix nodules [or amnion nodosum] indicate prolonged extreme oligohydramnios and pulmonary hypoplasia. An adherent clot suggests that an abruption has occurred. Any of these abnormal findings should be noted [3,25,26].

The placenta should be essentially odorless except for the slight odor of fresh blood. Foul odor indicates infection. This should be noted, and the physician should be informed [3,25,26].

Membranes should be assessed and noted to be present [i.e., not retained inside the uterus]. The number of membranes should be determined in the case of multiple gestations [3,25,26].

The umbilical cord should be assessed for appearance, length, and diameter. The appearance of the insertion site should be documented, noting intactness, the number of vessels, and color. The umbilical cord should be a pearl ivory color, and any deviations from this color should be noted. The umbilical cord length is normally between 55 and 60 cm, with 5% of cords shorter than 35 cm and 5% longer than 80 cm [25,26,27]. Shorter length may be the cause of decreased fetal movement, intrauterine constraint, placental abruption, or cord rupture [27]. A longer cord makes entanglement or prolapse more likely. The cord diameter at term is generally about 1.5 cm and should be relatively uniform throughout, without strictures. The Wharton's jelly should be firm, with compression a likely result if the cord is thin [3,26,27].

IMMEDIATE POST-BIRTH CARE

Approximately 85% to 90% of infants make the transition from intrauterine to extrauterine life with no assistance necessary [28,29]. However, for the remaining few newborns, some assistance may be required, ranging from simple stimulation to complete resuscitation.

All nurses should be familiar with the ABCs of resuscitation: airway, breathing, and circulation. Because newborns are wet when they are born, they can suffer rapid heat loss if a warm environment is not maintained [28]. Therefore, it is critical to maintain a warm, or thermoneutral, environment for the infant throughout the first hours and days of life. This can be accomplished by placing the infant on the mother's abdomen, with warm blankets placed over them both to maintain body heat. Alternatively, if the need for further intervention is anticipated, or if the caregiver prefers, the infant should be placed on a preheated radiant warmer.

As the infant is being dried with warm blankets, the nurse should also be evaluating the infant's airway, breathing, muscle tone, color, and gestational age. All of these things should be evaluated within the first 30 seconds of life. The airway should be cleared with a bulb syringe or mechanical suction, and the infant should be positioned in such a manner as to facilitate an obstruction-free airway. If, in the initial evaluation, the infant is found to be clear of meconium, is breathing or crying, has good tone, is pink, and appears to be term gestation, then routine care need only be provided [28]. Routine care is comprised of assuring that the infant is warm and dry and keeping the airway clear. According to Neonatal Resuscitation Program standards, further care is warranted if the newborn fails to respond to birth in this positive manner [28].

In the United States, antibiotic eye ointment for the prophylaxis of ophthalmia neonatorum is highly recommended in all newborns [30,31,32]. Ophthalmia neonatorum is the inflammation of the eyes resulting from exposure to gonorrhea or chlamydia as the infant passes through the birth canal and can lead to blindness [30]. Administration of vitamin K intramuscularly is also common in the United States to prevent hemorrhagic disorders [4]. Coagulation alteration is seen predominately in infants in the second or third day of life, specifically because factors VII, VIII, IX, and X are dependent on the synthesis of vitamin K [33,34].

APGAR SCORE

In 1953, an anesthesiologist named Virginia Apgar designed a tool for evaluating newborn infants [35]. The Apgar scores grade the infant's response to extrauterine life in five categories [36]:

• Heart rate

• Respiratory effort

• Muscle tone

• Reflex irritability

• Color

There are a maximum of 2 points possible in each category, for a total of 10 possible points. The Apgar determination is completed at one and five minutes of life. It is important to note that resuscitative measures should not be delayed while awaiting the one- and five-minute marks for Apgar determination.

Morbidity and mortality findings have been found to correlate with the five-minute Apgar score [37,38]. The one-minute Apgar score correlates with the pH of cord blood. The lower the score, the more acidotic the infant; in addition, infants with lower scores have worsening cardiorespiratory depression [35]. Some studies have suggested that the Apgar score loses clinical significance for infants of 23 to 25 weeks' gestation who survive their first 24 hours of life [39].

Heart rate can be determined either through auscultation of the apical pulsation or by palpating the umbilical cord. A heart rate greater than 100 beats per minute [bpm] is awarded a score of 2 points. A pulse of less than 100 bpm garners 1 point. An absent heartbeat would obtain zero points [35,36].

Assessment of the respiratory effort requires a multifaceted approach. Movement of air in and out of the lungs may be auscultated at the time that a respiratory rate is obtained. An infant with a good cry is awarded 2 points for respiratory effort. An infant that is making some attempt at breathing but may be categorized as slow or irregular will obtain only 1 point. An irregular breathing pattern, also known as periodic breathing, is a normal finding in some newborns. However, if periodic breathing is associated with nasal flaring, grunting, retractions, cyanosis, or decreased rate, further assessment and intervention may be required. A newborn with an absent respiratory drive will receive zero points [35,36].

The nurse considers muscle tone acceptable if the infant's elbows, hips, and knees are flexed and allow active extension of extremities. The infant should return to the gently flexed position after examination. An attitude of flexion is necessary to obtain 2 points. An infant with some flexion should be assigned 1 point. A limp infant would receive zero points [35,36].

Reflex irritability is noted as the infant reacts to noxious stimulation. An appropriate response to stimuli, such as suctioning or rubbing the soles of the feet, would be for the infant to cry. This response would be awarded 2 points. If the newborn grimaces in response to such stimuli, 1 point would be awarded for effort. If the infant shows no response, then zero points would be awarded [35,36].

Color can be assessed by noting the color of mucous membranes, the trunk, and the soles of the feet. The infant should be pink and not dusky. An infant who is completely pink, including the hands and feet, would be awarded 2 points in this category. An infant that is pink but is acrocyanotic [i.e., has blue hands and/or feet] would receive 1 point. An infant that is blue, gray, or dusky would receive zero points [35,36].

NEWBORN SCREENING

Newborn screening programs began in the early 1960s with the development of a screening test for phenylketonuria [PKU] [40]. Newborn screening in the United States is a public health program aimed at the early identification of a variety of serious conditions, including genetic disorders [e.g., cystic fibrosis, hearing loss] and endocrine disorders [e.g., congenital adrenal hyperplasia, primary congenital hypothyroidism] [40,41]. In 2003, all but four states were screening for only six of these disorders. By 2018, most states reported screening for at least 29 [of 35 recommended] genetic and endocrine disorders on the standardized uniform panel of core conditions [41,44].

The adoption of a uniform newborn screening panel has led to earlier lifesaving treatment and intervention for newborns with these disorders [42,43]. The number and types of disorders screened for vary by state, but generally are guided by the Recommended Universal Screening Panel, which was developed by the U.S. Department of Health and Human Services [40,44].

PERIODS OF REACTIVITY

All healthy newborns go through predictable periods of alertness and sleep that should be assessed and taken into consideration when performing the comprehensive physical examination. Distressed infants also progress through these stages but at a much slower rate [1]. These stages are called the first and second periods of reactivity.

The first period of reactivity generally lasts six to eight hours. For the first 30 minutes after birth, the newborn is generally very alert and active. The infant will usually have a vigorous suck reflex during this time, and it is generally an excellent time to begin breastfeeding. The infant will have open eyes and will be interested in looking around. Physiologically, the infant's respiratory rate may be increased and the lungs will sound quite wet. The heart rate may be increased, bowel sounds are active, mucus production is increased, and body temperature may be slightly decreased [1,45].

After this initial period of alertness, the newborn will go into a deep sleep that generally lasts from two to four hours, though it may continue much longer. During this period, the infant is very calm. Attempts to stimulate the infant will generally be unsuccessful. Ideally, the physical examination should be completed before this time and the infant can then be left alone to sleep. Physiologically, the infant will experience a decrease in respiratory rate, mucus production, and temperature and will likely not void or stool [1,45].

The second period of reactivity, which usually lasts two to five hours, begins when the newborn wakes from this deep sleep state. The infant is generally very alert once again and showing signs of hunger. This is an excellent opportunity for the infant and family to interact with each other and for the nurse to begin some teaching regarding hunger cues and other ways that the infant may communicate needs. Physiologically, the newborn's heart and respiratory rates increase, the gag reflex is active, and the production of mucus and meconium resumes [1,45].

ASSESSMENT OF ATTACHMENT

Throughout the initial postbirth care and physical exam of the newborn, the nurse should be alert for signs of attachment forming between the infant and the parents. It is important for the nurse to look for those behaviors that lead to the successful process of attachment and bonding between parent and infant [1].

Unlike the physical examination, which uses concrete guidelines, the assessment of attachment requires the nurse to observe interactions and speak with the new parents regarding their expectations, dreams, and desires for their infant. This part of the newborn assessment can be challenging in today's hospital environment of shorter stays, but it is imperative in ensuring the well-being of the infant.

The following guidelines may be used when assessing infant-parent attachment [1]:

• When the infant is brought to the parents, do they reach out for the infant and call the infant by name?

• Do the parents speak about the infant in terms of identification [i.e., who the infant looks like; what appears special about their child over other infants]?

• When the parents are holding the infant, what kind of body contact is there? Do they feel at ease in changing the infant's position? Are fingertips or whole hands used? Are there parts of the body they avoid touching or parts of the body they investigate and scrutinize?

• When the infant is awake, what kinds of stimulation do the parents provide? Do they talk to the infant, to each other, or to no one? How do they look at the infant [e.g., direct visual contact, avoidance of eye contact, or looking at other people or objects]?

• How comfortable do the parents appear in terms of caring for the infant? Do they express any concern regarding their ability or disgust for certain activities, such as changing diapers?

• What type of affection do they demonstrate to the newborn, such as smiling, stroking, kissing, or rocking?

• If the infant is fussy, what kinds of comforting techniques do the parents use, such as rocking, swaddling, talking, or stroking?

GENERAL APPEARANCE ASSESSMENT

After the prenatal history has been obtained, the placenta has been evaluated, immediate postbirth care has been provided, and Apgar scores assigned, one can proceed with the physical examination. As with other facets of nursing care, the physical assessment always begins with the general appearance.

One important assessment strategy is to discuss the upcoming assessment with the infant's parents. Including the parents during the assessment allows the healthcare provider to point out both normal and abnormal findings. Optimizing this time with the parents assists them in understanding their infant and allows them to ask questions [46].

The following findings are considered warning signs that may be seen during the general assessment [35]:

• Axillary temperature less than 36.1°C or greater than 37.2°C

• Heart rate less than 100 bpm or greater than 160 bpm

• Respiratory rate less than 30 or greater than 60 breaths per minute

• Cyanosis

• Jaundice

• Periods of apnea lasting more than 15 seconds

• Lack of movement or responsiveness

• Hypotonic or hypertonic position

• Lack of interest in environment

Should these findings be noted, they would warrant immediate further investigation and treatment.

As noted, maintaining a thermoneutral environment is an important consideration. The assessment of any newborn should be conducted in a warm, well-lit environment. Cooler environments stress the newborn and may lead to inaccuracies in assessment. For example, incorrect findings may be made if the patient is found to look blue, experience bradycardia, or have cold hands and feet due to a hypothermic environment.

The assessment of the infant can be conducted through inspection, auscultation, and palpation. Inspection should occur before physical contact is made with the infant, though the need may arise to remove blankets, diapers, or clothing in order to complete a thorough inspection. Whenever possible, complete the observation portion of the assessment before touching the newborn. Observe the infant's position, temperament, sleep or wake cycle, color, movement, and respiratory pattern before disturbing the infant. Once the newborn has been disturbed, he or she may become agitated, resulting in a guarded posture, increased respiratory rate, and temperament changes. During the assessment, an inspection of the infant's activity level, color, respiratory effort, ease of movement, and posture should be noted [3]. During inspection, one should also note the appearance of any dysmorphic features. The finding of three or more dysmorphic features may warrant chromosome analysis [29,47].

During inspection, the activity level should be noted for sleep states progressing to irritability during the more intrusive parts of the exam [48]. There are six identified sleep states: deep sleep; active sleep; drowsy, in-between state; awake alert; alert and fussy; and crying [33,48,49]. The infant should be assessed in an awake alert state, which has been identified as the infant being bright, focused, and minimally active [29,33,48,49]. Motor activity, such as tremulousness, irritability, and defensiveness, should be noted both before and during the assessment [48].

Proper lighting is important as the accurate assessment of a newborn's skin can be useful in determining problems. Even if a newborn is slightly icteric at birth, making this determination can be useful in following the infant for potential problems related to jaundice. If the lighting of the examination room is inadequate, the slight appearance of jaundice may be overlooked. Color is important in determining pulmonary and cardiac involvement and thermoregulation, as well as other organ function in the newborn. Changes in the infant's color may occur throughout the exam when the infant cries, becomes cool, or is irritable. Assessment should be made for jaundice, cyanosis, pallor, and plethora [3]. It is important to note that acrocyanosis, the blue or dusky hands and feet with a pink trunk and mucous membranes, is frequently found and does not indicate a major problem.

Respiratory effort should be assessed by noting the rate and quality of breaths. Depth of breathing, retracting, grunting, nasal flaring, head bobbing, and posture changes associated with inadequate effort should be noted. Periodic breathing by the newborn [i.e., taking several breaths in a row then pausing for up to 15 seconds] is a normal finding. However, grunting, flaring, retractions, and head bobbing warrant further investigation [29]. A full discussion of respiratory assessment follows later in this course.

During inspection, resting posture offers many clues to the health of a newborn. In a healthy, full-term newborn, the posture should be that of flexion [1,29]. Muscle tone, including the amount of flexion or extension, should be assessed. Asymmetry of extremities, comparison of upper and lower extremities, and flaccid posture or contraction should be noted and further evaluated during the exam. The newborn's ease of movement should be noted throughout the assessment. The levels of fluidity and spasticity should be observed.

GENERAL MEASUREMENTS

General measurements should be performed on each newborn. Infants who are found to have values outside the accepted range may require further evaluation and treatment. Weight, length, head circumference, and chest circumference measurements allow the practitioner to find abnormalities. Plotting these abnormalities provides a quick reference for comparisons with acceptable ranges.

WEIGHT

Birth weight is an important indicator of perinatal morbidity and mortality [2]. When weighing a newborn, it is important to do so when the infant is not wearing a diaper. If a diaper is in place, subtract the weight of the diaper from the total weight. A strategy to prevent weight inaccuracies is to use the same scale each time the patient is weighed. This will control for differences in zero balancing between two scales. If an infant is being weighed on a bed that has a built-in scale, it is important to remove any extra sheets, toys, or diapers. A further consideration in weighing the critically ill newborn is lifting the intravenous infusion lines, as well as other pieces of equipment, such as ventilator tubing, so they do not cause an inaccurately high measurement. A list of the items that the bed was initially zeroed with should be recorded for easy access. These items should remain on the bed during each weighing, so the zero balance of the scale remains at a constant and only the infant's weight is measured. For example, removing a critically ill newborn from the bed each time the weight must be assessed may not be feasible. Instead, the foam mattress and gel devices need not be removed each time the infant is weighed. One of the most important factors in monitoring an infant's fluid balance is weight [50]. Birth weight should be measured soon after birth because the fluid loss that occurs after birth begins fairly rapidly [1].

Classification of weight may be used independent of gestational age. Extremely low birth weight infants weigh less than 1,000 grams, very low birth weight newborns weigh less than 1,500 grams, and low birth weight newborns weigh less than 2,500 grams [51]. Normal weight in a term newborn ranges from 2,500 to 4,000 grams [52,53].

Another common classification system for identifying birth weight-related risk factors uses the terms large for gestational age [LGA], appropriate for gestational age [AGA], and small for gestational age [SGA] [Table 1]. An LGA infant weighs more than the 90th percentile at any given gestational age [54]. At term, an LGA infant would be considered one that weighs more than 4,000 grams. An AGA infant is one that falls anywhere between the 10th and the 90th percentile for his or her given age [53]. At term, this would be any infant weighing between 2,500 and 4,000 grams. An SGA infant falls below the 10th percentile for his or her gestational age [53]. At term, an SGA infant weighs less than 2,500 grams. Infants are categorized as term when they are born between the first day of week 37 to 42 weeks of gestation [55]. Before 37 weeks, the newborn may be considered premature, and after 42 weeks, the newborn should be classified as post-term [55] [Table 2]. Correctly categorizing the newborn can aid in determining future risk factors.

WEIGHT AND PERCENTILE CLASSIFICATIONS

GESTATIONAL AGE CLASSIFICATION