From the Guidelines
The expected weight for a premature baby at 21 days can be estimated by aiming for a weight gain of 17-20 g/kg per day after the initial postnatal weight loss, as recommended by the espghan/espen/espr/cspen guidelines on pediatric parenteral nutrition: energy 1. To determine the expected weight, we need to consider the baby's birth weight, gestational age, and individual health circumstances. Generally, premature babies should regain their birth weight by 2-3 weeks of life and then gain approximately 15-30 grams per day (about 0.5-1 ounce daily). For example, a baby born at 32 weeks gestation weighing 1500 grams might be expected to weigh approximately 1800-2100 grams by 21 days of life. However, weight gain patterns vary significantly among premature infants. Some key points to consider include:
- Smaller or more premature babies (born before 28 weeks) may gain weight more slowly initially 1.
- Nutritional support plays a crucial role in weight gain, with premature infants typically requiring higher caloric intake (110-130 calories/kg/day) than full-term babies 1.
- Parents should track their premature baby's weight with their healthcare provider, who will plot growth on specialized premature infant growth charts that account for gestational age 1.
- Any significant deviation from the expected growth pattern should prompt medical evaluation to identify and address potential feeding issues or health concerns 1. The energy requirements for premature infants correspond to the sum of total energy expenditure (TEE) and the energy stored in new tissue (i.e., growth), with a recommended energy intake of 90-120 kcal/kg/day to approximate intra-uterine lean body mass accretion and growth 1.
From the Research
Expected Weight for Premature Babies
The expected weight for a premature baby at 21 days is not explicitly stated in the provided studies. However, some studies provide information on the growth and development of premature infants.
- The study 2 discusses the care of preterm or low birthweight infants, but it does not provide specific information on the expected weight of premature babies at 21 days.
- The study 3 reviews the requirements for protein and amino acids necessary to achieve normal growth and development of preterm infants, but it does not provide information on the expected weight of premature babies at 21 days.
- The study 4 reviews the trace mineral requirements for preterm infants, but it does not provide information on the expected weight of premature babies at 21 days.
- The study 5 discusses the micronutrient intakes and health outcomes in preterm infants, but it does not provide specific information on the expected weight of premature babies at 21 days.
- The study 6 discusses the nutritional supplements to improve outcomes in preterm neonates, but it does not provide information on the expected weight of premature babies at 21 days.
Growth and Development of Premature Infants
Some key points related to the growth and development of premature infants include:
- Preterm infants require considerably more protein to achieve normal intrauterine growth rates than is commonly fed to them during their first postnatal days 3.
- Protein requirements at 24-30 weeks' gestation are as high as 4 g/kg/day, decreasing to 2-3 g/kg/day by term 3.
- Inadequate nutrient stores at birth are an inevitable consequence of being born prematurely, and preterm infants have high nutrient requirements, which increase with earlier gestational ages 4.
- Deficiency or excess of specific micronutrients is common in preterm infants and can have many effects on health outcomes, ranging from life-threatening electrolyte disturbances to long-term effects on growth, brain development, bone health, and the risk of retinopathy of prematurity (ROP) 5.
Unfortunately, there are no research papers provided that directly answer the question of what is the expected weight for a premature baby at 21 days.