Definition of prematurity:
Preterm birth is known as an early delivery done before the 37th week of gestational age. The burden of preterm newborns has been rising during the last 20 years worldwide (Acolet et al., 1993).
Problems of prematurity: Preterm infants have a smaller birth weight than full-term infants and also have feeding difficulties due to suckling troubles or incoordination of swallowing and breathing. Also, neonatal intensive care unit (NICU) admitted premature infants are exposed to many stressful conditions that can affect their weight. In addition, weight gain becomes the main criteria for hospital discharge following intensive care treatment (Beck et al., 2010). …show more content…
Hematotrophic phase: After third week of gestation, substances are transported passively via intervillous space.
(Anju et al., 2011)
Growth rate: Growth rate of fetus is linear up to 37 weeks of gestation, after which it plateaus (Anju et al., 2011).
A slow growth rate and preterm labor can cause a low birth weight. Low birth weight (below 2000 grams) can increase the likelihood of schizophrenia by almost four times (Subero, 2013).
Normative growth data: Normative growth data are available for healthy term infants. However, data are limited for preterm infants during both hospitalization and after discharge:
●Weight increases by 208 g/week from 28 weeks gestation till 6 months of age. After birth, infants gain 30 g/day till 3 months of age and 20 g/day between 3 and 12 months of age.
●Length increases by 1.1 cm/week from 28 to 40 weeks gestation; after birth, growth is 0.75 and 0.5 cm/week for the first three and the following two to three months, respectively.
●Head circumference increases by 0.75 cm/week during the last trimester, 0.5 cm/week from birth to three months of age, and then approximately 0.25 cm/week. (Babson, …show more content…
These include the Olsen, Bertino, and Fenton growth charts. In these charts advanced mathematical modeling approaches are used such as the Lambda Mu Sigma method (LMS) in which the calculation of precise Z-scores and centiles is allowed. So many questions about which charts should be used because their number has increased (Fenton and Kim, 2013).
The Olsen and Bertino charts depend on large cohorts of newborn infants, and after discarding pregnancies with conditions affecting fetal growth, have established references for new born infants’ birth weight across a wide range of gestational age. Consequently, they are perfectly suitable for determining if babies are born large for gestational age (LGA), small for gestational age (SGA), or appropriate for gestational age (AGA) (Bertino et al., 2010 & Olsen et al., 2010).
1) The Olsen chart:
Olsen growth chart for premature infants – Girls FIGURE 1: Intrauterine growth curves for girls. (A) Weight-for-age in grams (gm). (B) Length- and head circumference (HC)-for-age. Of note, 3rd and 97th percentiles on all curves for 23 weeks should be interpreted cautiously given the small sample size. Reproduced with permission from: Pediatrics, Vol. 125, Pages