ARCHAIC REFLEXES AND MATURATION ASPECTSOF NEWBORN INFANTSMIHAI CRAIU MD PhD

ALFRED RUSESCU CHILDRENS HOSPITAL

ARCHAIC REFLEXES 1Reflexes are an involuntary reaction of a muscle or a group of muscles to an external stimulus. Many parents are surprised when they realize that their baby can do a lot of movements during first days of his life

ARCHAIC REFLEXES 2While some reflexes are kept for the whole life (respiratory reflex), other reflexes disappear, giving way to voluntary, controlled motor habits and skills. Neonatology treats reflexes like a peculiar temporary equipment for the first period, as babys organism should know how to fulfill some vital functions right after birth, as theres no time to learn.

ARCHAIC REFLEXES 3All archaic reflexes are seen in infancy, up until about one year of age.Most frequent examined are :Suckling reflexRooting reflexPalmar and plantar grasp reflexMoro reflexAutomatic walking reflex

SUCKLING REFLEXDuring first nursing a mother can notice that suckling reflex is highly developed in her baby.A baby begins suckling strongly, when he feels a nipple or even a finger in his mouth.

AUTOMATIC WALKING REFLEXIf you raise a newborn the way that his feet would be in contact with a hard surface, he begins walking automatically (running reflex). This reaction disappears in 3-6 weeks.

GRASPING REFLEXIf you touch a baby`s palm with a finger or some object, he will grasp it in his fist so strong, that you will be able to raise him a little. This reflex will disappear when a baby learns taking objects, on about 4th month of life. Feet also have grasping reflex. When you press a babys feet, his toes begin bending and remain in this position until stimulation stops. When a baby learns standing this reflex will disappear.

MORO REFLEXGripping reflex (also called Moro`s reflex) is a protective reaction of organism. Noise or change of position induces this reflex. He tosses his arms and legs up very fast, like he wants gripping something. On 4th month of life this reaction disappears.

BREST CRAWLING REFLEXEvery newborn, when placed on her mothers abdomen, soon after birth, has the ability to find her mothers breast all on her own and to decide when to take the first breastfeed. Was first described in 1987 at the Karolinska Institute in Sweden (Widstrm et al, 1987): Immediately after birth the child was dried and laid on the mothers chest. In the control group a regular behavioural sequence, previously not described in the literature, was observed. After 15 minutes of comparative inactivity, spontaneous sucking and rooting movements occurred, reaching maximal intensity at 45 minutes. The first hand-to-mouth movement was observed at a mean of 34 2 minutes after birth and at 55+ minutes the infant spontaneously found the nipple and started to suckle.

CRONOLOGY OF REFLEXES28 weeks all present at some extent excepting automatic walking32 weeks Moro reflex is complete34 weeks grasping reflex is complete37 weeks all present and complete, excepting automatic walking40 weeks automatic walking reflex complete

MATURATIONGestational age can be estimated starting from firs day of the last recorded menstrual cycle of the gravidaProbable birth day 270 +/- 10 daysTerm gestation 38-42 weeksPremature newborn < 38 weeksPostmature newborn > 42 weeks

WEIGHT 1Intrauterine growth is variable, depending on maternal, placental and fetal factorsNewborn weight should be concordant with gestational age.If weight is below the estimated value the child will be diagnosed as SGA (small for gestational age) or dismature.

WEIGHT 2Small newborn weight, but concordant with gestational age will be diagnosed as prematurity.At 30 weeks 1600 g birth weightAt 34 weeks 2600 g birth weightAt 38 weeks 3200 g birth weightAt 42 weeks 3800 g birth weight

WEIGHT 3Small newborn weight, can be classified as prematurity grade I - IVGrade I prematurity 2000 - 2500 gBWGrade II prematurity 1500 2000 gBWGrade III prematurity 1000 1500 gBWGrade IV prematurity < 1000 gBW

PREMATURITY

SGA (small for gestational age)

GESTATIONAL AGE EVALUATION IN-UTERO

NEUROMATURATION

References "New Ballard Score, expanded to include extremely premature infants," by Ballard, JL, et al, Journal of Pediatrics, September 1991, page 417.

Scoring System for Clinical Assessment of Klimeks maturation index in newborn infants.

What is the normal gestational term for humans?Naegeles Rule: The standard definition for gestational term is 266 days from conception to the date of the babys birth. This is also defined as 280 days, or 40 weeks, from the first day of the mothers last menstrual period, a definition which assumes that the mother ovulates on day 14 of a 28 day menstrual cycle.

What is the normal gestational term for humans?This definition is based on observations, first reported by Franz Naegele in 1812, who believed that pregnancy lasted ten lunar months from the last menstrual period.The formula used to calculate due date is:(LMP + 7 days) 3 months = Due Date

Mittendorfs Observations of Gestational Term.In the 1980s, Mittendorf noticed that birth dates for women in his practice, primarily second-generation Irish-Americans, averaged seven days past their due dates. He reviewed his records, then went on to review records of 17,000 births, and determined the average healthy, white, private-care, primiparous woman averaged 288 days from LMP to birth: 8 days longer than Naegeles rule.

Mittendorfs Observations of Gestational Term.Mittendorf and others have determined several factors that affect gestational term:ethnicity, parity, nutrition, substance use, mothers age, mothers size. Based on Mittendorfs data, a more appropriate formula might be: (LMP 3 months) + 15* Days = Due Date

* Add 10, rather than 15, if mother is non-white, or multiparous

Normal Variations in Gestational Term

From the wide range in birth dates, it is clear that some variation is normal. Some examples of known variations: Multiparous women average 283 days, versus the 288 days of multiparous women. Black women averaged 8.5 days fewer than white women of similar socioeconomic status.Other studies indicate that for multiple births, each additional baby in the uterus shortens the pregnancy by 4 weeks on average.

GESTATIONAL AGE

TERM vs PRETERMGESTATIONAL AGE not BIRTH WEIGHT