РАЗВИТИЕ ПЛОДА И НОВОРОЖДЕННОГО [ prenatal development of the fetus and neonatal development of the newborn ] (Лат.: natalis - относящийся к рождению, связанный с моментом рождения; 1826).
Развитие плода человека, или преднатальное развитие зародыша человека, или развитие зародыша человека на стадии плода - это развитие зародыша человека в интервале времени от девятой недели беременности до начала родов. Развитие новорожденного ребёнка, или постнатальное развитие человека, или антенатальное развитие человека - это развитие новорожденного ребёнка в интервале времени от момента рождения до одного месяца после родов.
Часто используемое определение «пренатальный» - ложная калька (от англ.: pre-natal). В русском языке приставка «пре-» имеет значение, не относящееся к смыслу данного слова, маскирующее смысл термина. Латинской приставке «prae-» и английской «pre-» в русском языке соответствует приставка «пред-». Поэтому по-русски правильно говорить «преднатальный», но не «пренатальный». Правильное написание и произношение более определенно, не требует дополнительного разъяснения, является однозначным. Примеры: предсинаптический нейрон, предсинаптическая терминаль, предсинаптическая мембрана, предсинаптические процессы.
Таблица. Характеристики плода на различных этапах развития. Модификация: Stables D., Rankin J., Eds. Physiology in Childbearing: with Anatomy and Related Biosciences. Elsevier, 2010, 792 p., см.: Физиология человека: Литература. Иллюстрации. |
№ |
Сроки развития, недели |
Морфогенетические процессы |
1 |
9-я |
Размер головки плода составляет половину его длины, темя - крестец = The fetal head measures half the crown - rump length |
2 |
10-я |
Интестинальные клетки объединяются и образуют полости тела = Intestinal cells have all re-entered the body cavity |
3 |
12-я |
• Длина плода увеличивается более чем вдвое = Fetal length has more than doubled
• Верхние конечности достигают нормальной длины относительно длины туловища, но нижние конечности остаются короткими = The upper limbs have attained their relative length in comparison to the trunk but the lower limbs remain short
• Появляются развивающиеся формы наружных гениталий = The mature forms of the external genitalia appear
• Уменьшается образование эритроцитов в печени и увеличивается их образование в селезёнке = There is a decrease in red cell formation in the liver and onset in the spleen
• Начинается образование и экскреция мочи = The formation and excretion of urine begins
• Начинаются и проявляются движения мышц плода = The beginning of fetal muscle movement occurs
• Слипшиеся веки = The eyelids fuse
|
4 |
13-16-я |
Этап очень быстрого роста = This is a period of very rapid growth |
5 |
16-я |
• Размеры головки плода стали меньше размеров туловища. Нижние конечности достигли правильных пропорций по отношению к туловищу = The head is now smaller in comparison to the trunk and the lower limbs have reached their correct proportions
• При радиологической фильмографии может быть отчётливо виден скелет = The skeleton can be seen clearly on X-ray films
• Лицо приобретает форму лица человека, глаза размещены больше кпереди, чем латерально = The face is more human, the eyes pointing anteriorly rather than laterally
• Ушные раковины смещены на боковые поверхности головы = The external ears have moved to their positions on the sides of the head
|
6 |
17-20-я |
• Рост замедляется = Growth slows down
• беременая ощущает движения плода = Fetal movements are felt by the mother
• Кожа плода для защиты от амниотической жидкости покрывается первородной смазкой = The skin is covered by vernix caseosa, to protect it from amniotic fluid
• Все тело плода покрывается развивающимися пушковыми волосами = Lanugo has developed all over the body
• Становятся видимыми волосы на голове и на надбровных дугах = Head and eyebrow hair become visible
• Формируются высокометаболизируемые энергетические резервы бурого жира = Highly metabolic brown fat is formed
|
7 |
21-25-я |
• Начинается выработка сурфактанта в лёгких = Surfactant production in the lungs begins
• К концу этого интервала развития плод может быть способен к внеутробному выживанию = Towards the end of this period survival becomes possible
• Кожа теряет резервный подкожный жир и становится морщинистой = The skin lacks subcutaneous fat and is wrinkled
• Из-за развития кровеносных капилляров непосредственно у поверхности кожи, она становится красной = The skin appears red because of blood capillaries just under the surface
• Плод имеет периоды сна и бодрствования и реагирует на звуки = The fetus now has periods of sleep and activity and responds to sound.
|
8 |
26-29-я |
• Лёгкие способны к осуществлению внешнего дыхания и к газообмену = The lungs are capable of breathing and allowing gas exchange
• Нервная система способна регулировать ритмические дыхательные движения и температуру тела плода = The nervous system controls rhythmic breathing movements and body temperature
• Происходят внутриматочные дыхательные движения плода = Intrauterine respiratory movements occur
• Открываются/закрываются глаза = The eyes re-open
• Хорошо развиты волосы на голове и пушковые волосы на теле = Head and lanugo hair are well developed
• Под кожей развивается белая подкожная жировая клетчатка = White, subcutaneous fat is laid down under the skin
• К 28-й неделе к эритропоэзу в селезёнке присоединяется эритропоэз в костном мозге = At 28 weeks erythropoiesis ends in the spleen and begins in the bone marrow
|
9 |
30-34-я |
• Развивается зрачковый рефлекс на свет = The papillary light reflex is present
• Жировые энергетические резервы плода составляют ~8% общей массы его тела = Body fat expands to 8% of total body weight
• Кожа плода непрозрачная и гладкая = The skin is opaque and smooth
• К 32-й неделе развития большинство плодов способно к внеутробной жизни = From 32 weeks most fetuses will survive
• С лица исчезают пушковые волосы = Lanugo disappears from the face
• Плод начинает резервировать железо = The fetus begins to store iron
|
10 |
35-38-я |
• Укрепляется хватательный рефлекс = The grasp is firm
• Большинство плодов пухлые = Most fetuses are plump
• К 36-й неделе развития окружности живота и головы плода приблизительно равны. Позже окружность живота становится больше. Рост плода постепенно замедляется до начала родов = At 36 weeks head and abdominal circumferences are equal. Later the abdominal circumference becomes
greater. Growth slows towards term • К 38-й неделе развития жировые энергетические резервы плода составляют ~16% общей массы тела плода = By 38 weeks body fat is 16% of body weight
• У плодов обоего пола присутствует ткань молочных желёз = Breast tissue is present in both sexes
• Яички опускаются в мошонку = The testes are in the scrotum in males
• Ногти вырастают до концов пальцев = The nails reach the tips of the fingers
• С поверхности тела исчезают пушковые волосы = Lanugo disappears from the body
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Схема. Зажим для пережатия пуповины новорожденного. Модификация: Stables D., Rankin J., Eds. Physiology in Childbearing: with Anatomy and Related Biosciences. Elsevier, 2010, 792 p., см.: Физиология человека: Литература. Иллюстрации.
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Схема. Относительные размеры плода в различные стадии его развития. Модификация: Stables D., Rankin J., Eds. Physiology in Childbearing: with Anatomy and Related Biosciences. Elsevier, 2010, 792 p., см.: Физиология человека: Литература. Иллюстрации.
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Схема. Пропорции тела развивающегося плода. Модификация: Stables D., Rankin J., Eds. Physiology in Childbearing: with Anatomy and Related Biosciences. Elsevier, 2010, 792 p., см.: Физиология человека: Литература. Иллюстрации.
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Примечание:
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К 9-й неделе развития плода диаметр его головы составляет приблизительно половину длины его тела (длина тело - крестец). К 38-й неделе окружности головы и живота плода приблизительно равны. Позже окружность живота плода может становиться больше окружности головы. На схеме изображены относительные размеры. |
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Далее
Gomella T.L., Cunningham M.D., Eyal F.G., Zenk K.E., Eds. Neonatology: Management, Procedures, On-Call Problems, Diseases, Drugs = Неонатология. Управление, заболевания, процедуры, медикаменты, Lange Medical Books/McGraw-Hill, 2004, 953 p. Учебное пособие. . Доступ к данному источнику = Access to the reference. URL: http://www.tryphonov.ru/tryphonov/serv_r.htm#0 quotation
с. 18-
PRENATAL DIAGNOSIS
I. First-trimester screening. Maternal serum can be analyzed for certain biochemical markers that,
in combination with ultrasound measurement of the fetal nuchal translucency, can be used to
calculate a risk assessment for trisomies 18 and 21. In the first trimester, these serum markers are the
free b-human chorionic gonadotropin (hCG) and pregnancy-associated plasma protein A (PAPP-A).
It is an effective screening tool, with a detection rate of 87-92% for trisomy 21 and fewer falsepositive
results than the traditional triple-screen test (alpha-fetoprotein [AFP], unconjugated estriol,
and hCG). First-trimester screening is performed between 10 and 13 weeks' gestation and requires
confirmation of a chromosomal abnormality by an invasive genetic test (usually chorionic villus
sampling [CVS]).
II. Second-trimester screening. Two common second-trimester tests are the maternal serum AFP
(MSAFP) and the triple-screen test. The MSAFP is a sensitive marker for open neural tube defects,
whereas the triple-screen test yields a risk assessment for open neural tube defects as well as
trisomies 18 and 21. These tests are usually performed between 15 and 20 weeks' gestation and
require an invasive test to confirm the diagnosis of a chromosomal abnormality (usually
amniocentesis). The usefulness of the triple-screen test is limited by its high number of false-positive
test results.
III. Ultrasound testing. Ultrasound examination is used in the following circumstances.
A. Calculation of gestational age. Measurement of the crown-rump length between 8 and 12
weeks' gestation allows for the most accurate assessment of gestational age, to within 5-7 days. After
the first trimester, a combination of biparietal diameter, head circumference, abdominal
circumference, and femur length is used to estimate gestational age and fetal weight. Measurements
in the second trimester are accurate to within approximately 2 weeks and in the third trimester to
within 3 weeks.
B. Anatomic survey. A large number of congenital anomalies can be diagnosed reliably by
ultrasonography, including anencephaly, hydrocephalus, congenital heart disease, gastroschisis,
omphalocele, spina bifida, renal anomalies, diaphragmatic hernia, cleft lip and palate, and skeletal
dysplasia. Identification of these anomalies before birth can help determine the safest type of delivery
and the support personnel needed. Ultrasonography can also aid in determining fetal gender.
C. Assessment of growth and fetal weight. Ultrasonography is useful to detect and monitor both
intrauterine growth restriction (IUGR) and fetal macrosomia. Estimation of fetal weight is also
important in counseling patients regarding expectations after delivering a premature infant.
D. Assessment of amniotic fluid volume
1. Oligohydramnios (decreased amniotic fluid). This is associated with a major anomaly in
15% of cases. Rupture of membranes is the most common cause of oligohydramnios. Other causes
include placental insufficiency, renal anomalies, bladder outlet obstruction, karyotypic abnormalities,
and severe cardiac disease. The kidneys and the bladder can be seen with ultrasonography at ~14
weeks' gestation.
2. Polyhydramnios (hydramnios) (excess of amniotic fluid). Polyhydramnios is associated
with major anomalies in 15% of cases. It is associated with gestational diabetes, anencephaly, neural
tube defects, bowel obstruction such as duodenal atresia, multiple gestation, nonimmune hydrops
fetalis, and exstrophy of the bladder.
E. Assessment of placental location and presence of retroplacental hemorrhage. This is useful
in suspected cases of placenta previa or abruptio placentae.
F. Diagnosis of multiple pregnancy and determination of chorionicity. The determination of
chorionicity is made by examination of the fetal membranes and is best done by 14 weeks' gestation.
G. Determination of pregnancy viability. This is important in the first trimester, when fetal heart
motion can be detected at 6-7 weeks' gestation. It is also important in the case of a suspected fetal
demise later in pregnancy.
H. Assessment of fetal well-being:
1. Biophysical profile. Ultrasonography is used to assess fetal movements and breathing
activity.
2. Doppler studies. Doppler ultrasonography of fetal vessels, particularly the umbilical artery, is
a useful adjunct in the management of high-risk pregnancies, especially those complicated by IUGR.
Changes in the vascular Doppler pattern (ie, absent or reversed end-diastolic flow in the umbilical
artery) signal a deterioration in placental function and possibly a worsening fetal condition. The use
of Doppler ultrasonography has been associated with a 38-50% decrease in perinatal mortality in
high-risk pregnancies; however, no benefit in using this technique to screen a low-risk population has
been proven.
I. Visual guidance for procedures such as amniocentesis, CVS, percutaneous umbilical blood
sampling (PUBS), and some fetal surgeries (eg, placement of bladder or chest shunts).
IV. Amniocentesis. Amniotic fluid can be analyzed for prenatal diagnosis of karyotypic
abnormalities, in fetuses diagnosed with congenital defects, to determine fetal lung maturity, to
monitor the degree of isoimmunization by measurement of the content of bilirubin in the fluid, and
for the diagnosis of chorioamnionitis. Testing for karyotypic and congenital abnormalities is usually
done at 16-20 weeks' gestation. A sample of amniotic fluid is removed under ultrasound guidance.
Fetal cells in the fluid can be grown in tissue culture for genetic study. With visual guidance from the
ultrasonogram, the pregnancy loss rate related to amniocentesis is usually quoted at between 0.3%
and 0.5%. Early amniocentesis (before 13 weeks) is associated with a higher rate of fetal loss. This is
indicated
· In women older than 35 years, because of the increased incidence of aneuploidy (ie, trisomies 13,
18, and 21).
· In those who have already had a child with a chromosomal abnormality.
· In those in whom X-linked disorders are suspected.
· To rule out inborn errors of metabolism.
V. Chorionic villus sampling. CVS is a technique for first-trimester genetic studies. Chorionic villi
are withdrawn either through a needle inserted through the abdomen and into the placenta or through
a catheter inserted through the vagina and cervix into the placenta. The cells obtained are identical to
those of the fetus and are grown and analyzed. CVS can be performed in the first trimester (usually
between 10 and 12 weeks' gestation). Results can be obtained more quickly than with other methods
via fluorescence in situ hybridization (FISH) rapid chromosome analysis, thus enabling the patient to
have a diagnosis before the end of the first trimester. Indications are the same as for amniocentesis.
Reported complications after CVS can include pregnancy loss and limb abnormalities; however, if
CVS is performed after 70 days' gestation, there is no increased incidence of limb reduction defects.
Pregnancy loss rates after CVS are usually quoted as ranging from 0.6-0.8% but are highly operator
dependent.
VI. Percutaneous umbilical blood sampling. Under ultrasound guidance, a needle is placed
transabdominally into the umbilical vein. Samples of fetal blood can be obtained for karyotype, viral
studies, fetal blood type, and hematocrit. This also provides a route for in utero transfusion. This
technique is most often used in cases of fetal hydrops.
ANTEPARTUM TESTS OF FETAL WELL-BEING
I. Nonstress test. The nonstress test (NST) is used to detect intact fetal brainstem function. Fetal wellbeing
is confirmed if the baseline heart rate is normal and there are periodic increases in the fetal
heart rate. These accelerations are often associated with fetal movement. The following guidelines
can be used, although there may be variations between institutions.
A. Reactive NST. In a 20-min monitoring period, there are at least two accelerations of the fetal
heart rate 15 beats/min above the baseline fetal heart rate; each acceleration lasts at least 15 s.
B. Nonreactive NST. Fetal heart rate does not meet the criteria just mentioned during a prolonged
period of monitoring (usually at least 1 h). Note: There are many causes of a nonreactive NST
besides fetal compromise, including a fetal sleep cycle, chronic maternal smoking, and exposure to
medications such as central nervous system depressants and propranolol. Because of this low
specificity, a nonreactive NST should be followed by more definitive testing such as a biophysical
profile or a contraction stress test.
II. Biophysical profile. The biophysical profile (Table 1-1) is another test used to assess fetal wellbeing,
often when the NST has been nonreactive. An NST is performed along with an ultrasound
examination to evaluate fetal breathing movements, gross body movements, tone, and amniotic fluid
volume. A score of 8-10 is considered normal, 4-6 indicates possible fetal compromise, and 0-2
predicts high perinatal mortality. This test has not been adequately assessed at early gestational ages.
III. Contraction stress test. The contraction stress test (CST) is used to assess a fetus at risk for
uteroplacental insufficiency. A monitor is placed on the mother's abdomen to continuously record the
fetal heart rate and uterine contractions. An adequate test consists of at least three contractions, each
lasting at least 40- 60 s, within a period of 10 min. If sufficient contractions do not occur
spontaneously, the mother is instructed to perform nipple stimulation or oxytocin is administered by
intravenous pump. If oxytocin is needed to produce contractions for the CST, it is called an oxytocin
challenge test (OCT). Normally, the fetal heart rate increases in response to a contraction, and no
decelerations occur during or after the contraction. If late decelerations occur during or after
contractions, uteroplacental insufficiency may be present. The CST is contraindicated in patients with
placenta previa, those who have had a previous cesarean section with a vertical incision, and those
with high-risk factors for preterm delivery (ie, premature rupture of membranes or incompetent
cervix). Test results are interpreted as follows:
A. Negative (normal) test. No late decelerations occur during adequate uterine contractions. The
baseline fetal heart rate is normal. This result is associated with a very low perinatal mortality rate in
the week after the test.
B. Positive (abnormal) test. Late decelerations occur with at least two of three contractions over a
10-min interval. This result can signify poor fetal outcome, and depending on gestational age,
delivery is usually recommended.
C. Equivocal (suspicious) test. A late deceleration occurs with one of three contractions over a 10-
min interval. Prolonged fetal monitoring is usually recommended.
INTRAPARTUM TESTS OF FETAL WELL-BEING
I. Fetal heart rate monitoring. Continuous fetal heart rate monitoring has been the standard clinical
practice since the 1970s. However, it has not been shown to improve perinatal mortality compared
with intermittent auscultation of the fetal heart rate. The only clear benefit to continuous fetal
monitoring in labor is a decrease in neonatal seizures. An abnormal fetal heart rate pattern is 50%
predictive of low Apgar scores. Fetal heart rate monitoring may be internal, with an electrode
attached to the fetal scalp, or external, with a monitor attached to the maternal abdomen. The baseline
heart rate, beat-to-beat variability, and long-term variability are measured.
A. Baseline fetal heart rate. The baseline fetal heart rate is the rate that is maintained apart from
periodic variations. The normal fetal heart rate is 110-160 beats/min. Fetal tachycardia is present at
160 beats/min or more. Causes of fetal tachycardia include maternal or fetal infection, fetal hypoxia,
thyrotoxicosis, and maternal use of drugs such as parasympathetic blockers or beta-mimetic agents.
Moderate fetal bradycardia is defined as a heart rate of 90-110 beats/min with normal variability.
Severe fetal bradycardia is a heart rate of <90 beats/min. Common causes of bradycardia include
hypoxia, complete heart block, and maternal use of drugs such as b-blockers.
B. Variability. Fetal heart rate variability has traditionally been broken down into categories of
short-term (beat-to-beat) and long-term variability, although for most practical purposes they are
assessed together. In the normal mature fetus, there are slight rapid fluctuations in the interval
between beats (beat-to-beat variability). This indicates a functioning sympathetic-parasympathetic
nervous system interaction. An amplitude range (baseline variability) >6 beats/min indicates normal
beat-to-beat variability and suggests the absence of fetal hypoxia. Absence of variability may be
caused by severe hypoxia, anencephaly, complete heart block, and maternal use of drugs such as
narcotics or magnesium sulfate. Long-term variability refers to fluctuations in the fetal heart rate over
longer periods of time (minutes rather than seconds).
C. Accelerations. Accelerations are often associated with fetal movement and are an indication of
fetal well-being.
D. Decelerations. There are three types of decelerations (Figure 1-1).
1. Early decelerations. Early decelerations (decelerations resulting from physiologic head
compression) occur secondary to vagal reflex tone, which follows minor, transient fetal hypoxic
episodes. These are benign and are not associated with fetal compromise.
2. Late decelerations. Two types of late decelerations exist.
a. Late decelerations with maintained beat-to-beat variability. These are seen in the
setting of normal fetal heart rate variability. They are associated with a sudden insult (eg, maternal
hypotension) that affects a normally oxygenated fetus and signifies uteroplacental insufficiency. The
normal variability of the fetal heart rate signifies that the fetus is physiologically compensated.
b. Late decelerations with decreased beat-to-beat variability. These are associated with
decreased or absent fetal heart rate variability. They may represent fetal hypoxia resulting from
uteroplacental insufficiency. Maneuvers such as maternal oxygen supplementation and maternal
positioning in the left lateral decubitus position may improve fetal oxygenation and placental
circulation and should be attempted.
3. Variable decelerations. These are most frequently associated with umbilical cord
compression. They are classified as severe when the fetal heart rate decreases to <60 beats/min, the
deceleration is longer than 60 s in duration, or the fetal heart rate is 60 beats/min below baseline. If
beat-to-beat variability is maintained, the fetus is compensated physiologically and oxygenated
normally.
II. Fetal scalp blood sampling. Fetal scalp blood sampling is used during labor to determine the
fetal acid-base status when the fetal heart rate tracing is non-reassuring or equivocal. This procedure
can be performed only after rupture of membranes. It is contraindicated in cases of possible blood
dyscrasias in the fetus and with maternal infections caused by herpesvirus or HIV. A blood sample is
obtained from the fetal presenting part (usually the scalp but sometimes the buttocks), and the fetal
blood pH is determined. A pH of і7.25 has been shown to correlate (with 92% accuracy) with a 2-
min Apgar score of і7. The protocol for interpreting fetal scalp blood pH varies among institutions.
Complications of this test are scalp infections (in <1% of infants) and soft tissue damage to the scalp.
An example of one such protocol is as follows.
A. pH і7.20. Fetus is not acidotic; no intervention required.
B. pH 7.10-7.19. Fetus is preacidotic. Repeat sampling in 15-20 min.
C. pH <7.10. Fetus may be acidotic. Delivery is indicated.
III. Scalp stimulation/vibroacoustic stimulation. An acceleration in fetal heart rate in response to
either manual stimulation of the fetal presenting part or vibroacoustic stimulation through the
maternal abdomen has been associated with a fetal pH of >7.20. These tests are often used in labor to
determine fetal well-being in lieu of a scalp blood sampling; however, a lack of fetal response to
stimulation is not predictive of acidemia.
IV. Fetal pulse oximetry. This promising new technique is designed as an adjunct to nonreassuring
fetal heart rate tracings in order to reduce the number of unnecessary interventions. A normal fetal
oxygen saturation as measured by pulse oximetry (SpO2) is 30-70%. A pulse oximetry reading of at
least 30% has good correlation with a fetal pH of at least 7.20. Long-term studies are still needed to
evaluate this technique.
FIGURE 1-1. Examples of fetal heart rate monitoring. FHR, Fetal heart rate (beats
per minute); UC, uterine contraction (mm Hg); HC, head compression; UPI,
uteroplacental insufficiency; CC, cord compression. (Modified and reproduced,
from McCrann JR, Schifrin BS: Fetal monitoring in high-risk pregnancy. Clin
Perinatol 1974;1:149 with permission from Elsevier Science.)
TESTS OF FETAL LUNG MATURITY
I. Lecithin-sphingomyelin (L-S) ratio. Lecithin, a saturated phosphatidylcholine (the condensation
product of a phosphatidic acid and choline), can be measured specifically in amniotic fluid and is a
principal active component of surfactant. It is manufactured by type II alveolar cells. Sphingomyelin
is a phospholipid found predominantly in body tissues other than the lungs. The L-S ratio compares
levels of lecithin, which increase in late gestation, with levels of sphingomyelin, which remain
constant. The L-S ratio is usually 1:1 by 31-32 weeks' gestation and 2:1 by 35 weeks' gestation. The
following are guidelines to L-S ratios.
· L-S і 2:1: Lungs are mature (98% accuracy). Only 2% of these infants will experience
respiratory distress syndrome (RDS).
· L-S = 1.5-1.9:1: 50% of infants will experience RDS.
· L-S <1.5:1: 73% of infants will experience RDS.
Some disorders are associated with delayed lung maturation, and higher than normal L-S ratios may
be needed before fetal lung maturity is ensured. The two most common disorders are diabetes
mellitus (an L-S ratio of 3:1 is usually accepted as indicating maturity) and Rh isoimmunization
associated with hydrops fetalis. Acceleration of fetal lung maturity is seen in sickle cell disease,
maternal narcotic addiction, prolonged rupture of membranes, chronic maternal hypertension,
intrauterine growth restriction, and placental infarction. Differences may also occur in various racial
groups.
II. Phosphatidylglycerol. Phosphatidylglycerol appears in amniotic fluid at ~35 weeks, and levels
increase at 37-40 weeks. This substance is a useful marker for lung maturation late in pregnancy. It is
reported as either present or absent.
TABLE 1-1. BIOPHYSICAL PROFILE SCORING SYSTEM USED TO ASSESS FETAL WELL-BEING
Variable Normal (2) Abnormal (0)
Fetal breathing One episode >30 s in 30 min None or episode <30 s in 30 min
Body movement Three or more movements in
30 min
Fetal tone One episode or active limb or trunk extension with flexion
Two or less movements in 30 min
No movement
Nonstress test Reactive Nonreactive
Amniotic fluid One pocket of amniotic fluid
1 cm or more
No fluid pockets or pocket <1 cm
Based on guidelines from Manning FA et al: Fetal biophysical profile scoring: a prospective study
in 1184 high-risk patients. Am J Obstet Gynecol 1981;140:289. Reprinted with permission from
Elsevier Science
III. TDx fetal lung maturity (TDx FLM). This test (Abbott Laboratories, North Chicago, IL) measures
the relative concentrations of surfactant and albumin (milligrams of surfactant per gram of
albumin) in amniotic fluid and gives a result that helps assess fetal lung maturity. TDx FLM has
several advantages over L-S ratio: (1) Less technical expertise is required; (2) this test can be
performed more easily; and (3) results are obtained more quickly. Results are interpreted in the
following ways.
30-70 mg/g: The infant is at risk for immature lungs. Other conditions may weigh more heavily on
the decision to deliver early.
70 mg/g: The likelihood of RDS is small.
СИСТЕМА РЕПРОДУКЦИИ: ОГЛАВЛЕНИЕ
СИСТЕМА РЕПРОДУКЦИИ: ТАБЛИЦЫ
СИСТЕМА РЕПРОДУКЦИИ: ИЛЛЮСТРАЦИИ
СИСТЕМА РЕПРОДУКЦИИ: ЛИТЕРАТУРА
«Я У Ч Е Н Ы Й И Л И . . . Н Е Д О У Ч К А ?» Т Е С Т В А Ш Е Г О И Н Т Е Л Л Е К Т А
Предпосылка: Эффективность развития любой отрасли знаний определяется степенью соответствия методологии познания - познаваемой сущности. Реальность: Живые структуры от биохимического и субклеточного уровня, до целого организма являются вероятностными структурами. Функции вероятностных структур являются вероятностными функциями. Необходимое условие: Эффективное исследование вероятностных структур и функций должно основываться на вероятностной методологии (Трифонов Е.В., 1978,..., ..., 2015, …).
Критерий: Степень развития морфологии, физиологии, психологии человека и медицины, объём индивидуальных и социальных знаний в этих областях определяется степенью использования вероятностной методологии.
Актуальные знания: В соответствии с предпосылкой, реальностью, необходимым условием и критерием...
... о ц е н и т е с а м о с т о я т е л ь н о: — с т е п е н ь р а з в и т и я с о в р е м е н н о й н а у к и, — о б ъ е м В а ш и х з н а н и й и — В а ш и н т е л л е к т !
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