A mother brings her preteen daughter to the clinic for her first female examination. During the health assessment, the nurse should implement which technique to determine if the client has reached the age of menarche?

Choice A reason: Playing "peek-a-boo" is a normal behavior for a 6-month-old infant. It shows that the infant has developed object permanence, which is the understanding that objects and people still exist even when they are out of sight. This is a sign of cognitive development and social interaction.

Choice B reason: Turning head to locate sound is a normal behavior for a 6-month-old infant. It shows that the infant has developed auditory localization, which is the ability to identify the direction and distance of a sound source. This is a sign of sensory development and curiosity.

Choice C reason: Having doubled birth weight is a normal milestone for a 6-month-old infant. It shows that the infant has adequate growth and nutrition. The average birth weight for a full-term infant is about 3.4 kg (7.5 lb), and the average weight for a 6-month-old infant is about 6.8 kg (15 lb).

Choice D reason: Demonstrating startle reflex is an abnormal behavior for a 6-month-old infant. The startle reflex, also known as the Moro reflex, is an involuntary response to a sudden loud noise or movement. The infant will extend the arms and legs, arch the back, and then curl the arms and legs inward. This reflex is present at birth and usually disappears by 4 months of age. If the reflex persists beyond 6 months of age, it may indicate a neurological problem or developmental delay. The nurse should request further evaluation by the health care provider.

Choice A reason: Measuring abdominal circumference provides immediate, objective data about the degree of abdominal distention, which is a key sign of intestinal obstruction in a neonate who hasn’t passed meconium and is vomiting bilious secretions. Establishing a baseline girth measurement guides further assessment, helps detect rapidly worsening distention, and informs decisions about decompression and imaging studies.

Choice B reason: Although initiating an IV infusion is critical for fluid and electrolyte replacement in any vomiting infant, securing intravenous access should follow a focused assessment. Prioritizing assessment ensures you understand the severity of the obstruction and tailor fluid resuscitation and other interventions appropriately.

Choice C reason: Monitoring strict urinary output is not the first action that the nurse should take. This is because urinary output is not the most sensitive indicator of fluid status in infants, especially those with renal insufficiency or oliguria. Monitoring urinary output may also delay more urgent interventions, such as fluid resuscitation and decompression.

Choice D reason: Preparing for anorectal manometry is not the first action that the nurse should take. This is because anorectal manometry is a diagnostic test that measures the pressure and function of the anal and rectal muscles. It is not indicated for infants with suspected meconium ileus, which is a mechanical obstruction of the bowel by thick and sticky meconium. Preparing for anorectal manometry may also delay more urgent interventions, such as fluid resuscitation and decompression.