Fetal development stages

NCM 107, Well Mother and Babies

1. FETAL GROWTH AND
DEVELOPMENT
CARE OF THE FETUS
KATHERINE C. VILLARAN, RN,
MAN

3. 1758 -KASPARWOLFF
•PROPOSED THAT BOTH
PARENTS CONTRIBUTE
EQUALLY TO THE STRUCTURE
OF THE BABY/FETUS (THE
INFANT DURING
INTRAUTERINE LIFE)

4. THREE PERIODS OF FETAL
GROWTH AND DEVELOPMENT
1.PREEMBRYONIC-FIRST 2
WEEKS, BEGINNING WITH
FERTILIZATION
2.EMBRYONIC -WEEKS 3
THROUGH 8
3.FETAL –FROM WEEK 8 THROUGH
BIRTH

5. 1. PREEMBRYONIC
BEGINS WITH FERTILIZATION
(PREGNANCY)
FERTILIZATION (CONCEPTION OR
IMPREGNATION)
•IS THE UNION OF AN OVUM AND A
SPERMATOZOON
•USUALLY OCCURS IN THE OUTER
THIRD OF A FALLOPIAN TUBE
(AMPULLARPORTION)

6. •OVUM’S FUNCTIONAL LIFE -24
HOURS (48 HOURS AT THE
MOST).
•SPERM’S FUNCTIONAL LIFE –48
HOURS(72 HOURS THE MOST).

7. OVARY
ovum is extruded from the graafian follicle (OVULATION)
surrounded by zona pellucida (ring of
mucopolysaccharide
fluid) and corona radiata (a circle of cells)
propelled into a
nearby fallopian
tube by currents
initiated by the
fimbriae
peristaltic action
of the tube and
movements of the
tube cilia help
propel the ovum

8. Ejaculated spermatozoa
travel to
a less viscous cervical
mucous
2.5 mL of
fluid
containing
50 to 200
million
spermatozo
a per
milliliter,
or an
average of
400 million
(reach the cervix within 90 seconds and the
outer end of a fallopian tube within 5 minutes
after deposition)
SPERM (species-specific
reaction) Cervix -> body of the uterus ->
fallopian tubes through movement by
their flagella (tails) and uterine
contractions.
Sperm undergo changes in the plasma
membrane of its head and reveal the
sperm-binding receptor sites
(Capacitation)
cluster around the protective
layer of corona cells.

9. Spermatozoa releases Hyaluronidase(a
proteolytic enzyme) and dissolves the corona
cells protecting the ovum.
Once spermatozoon penetrated the
cell membrane of the ovum, the
latter changes
composition and become
impervious to other spermatozoa
ovum and
spermatozoon fuse to
form a zygote.
spermatozoon and ovum each carried 23 chromosomes
(22 autosomes and 1 sex chromosome), the fertilized
ovum has 46 chromosome. Sperm carry and X and a Y
chromosome; XY: male, XX: female.
FERTILIZATION

11. 3 FACTORS THAT AFFECTS
FERTILIZATION:
1. EQUAL MATURATION OF BOTH SPERM
AND OVUM
2. ABILITY OF THE SPERM TO REACH THE
OVUM
3. ABILITY OF THE SPERM TO PENETRATE
THE ZONA PELLUCIDA AND CELL
MEMBRANE AND ACHIEVE FERTILIZATION

12. (3 TO 4 DAYS) ZYGOTE REACHES THE BODY
OF THE UTERUS WITH 16 TO 50 CELLS
(MORULA)
FERTILIZATION
zygote migrates over the next 3
to 4 days toward the body of the
uterus,
mitotic cell division or cleavage
begins
first cleavage occurs at about 24 hours (day
2) [2 cells, 4 cells, 8 cells] ---blastomeres
occur at a rate of about one every 22
hours

13. morula continues to multiply as it floats free in the uterine
cavity
Large cells tend to collect at the periphery of the ball,
leaving a fluid space surrounding an inner cell mass
(blastocyst)
Blastocyst attaches to the uterine endometrium
blastocyst sheds the last residues of the corona
and zona pellucida
Blastocyst brushes against the rich uterine endometrium (Apposition)
attaches to the surface of the endometrium (Adhesion)
settles down into its soft folds (invasion)

14. IMPLANTED UPPER, POSTERIOR SURFACE OF THE
UTERUS
trophoblast cells (outer ring) produce proteolytic
enzymes that dissolve any tissue they touch
blastocyst establishes an effective communication
network with the blood system of the endometrium
(angiogenesis)
Blastocyst burrow deeply into the endometrium and
receive some basic nourishment of glycogen and
mucoprotein from the endometrial glands.

15. (8 TO 10 DAYS) IMPLANTATION (CONTACT BETWEEN
THE GROWING STRUCTURE AND THE UTERINE
ENDOMETRIUM ( ZYGOTE -> FETUS)
Trophoblastform the placenta and chorion and the
embryoblast cells is the portion of the structure that
will form the embryo, amnion, umbilical cord.

20. YOLK SAC-IS THE FIRST ANATOMICAL
STRUCTURE IDENTIFIED WITHIN
THEGESTATIONAL SAC. IT PLAYS A
CRITICAL ROLE IN EMBRYONAL
DEVELOPMENT BY PROVIDING NUTRIENTS,
SERVING AS THE SITE OF INITIAL
HEMATOPOIESIS, PROVIDING ENDOCRINE,
METABOLIC AND IMMUNOLOGICAL
FUNCTIONS AND CONTRIBUTING TO THE
DEVELOPMENT OF FETAL
GASTROINTESTINAL AND REPRODUCTIVE
SYSTEMS
-Disappears at 14-20 weeks.

21. EMBRYONIC AND FETAL
STRUCTURES
PLACENTA -
SERVE
AS THE FETAL
LUNGS,
KIDNEYS, AND
DIGESTIVE TRACT
IN UTERO

22. DECIDUA (UTERINE
ENDOMETRIUM)
•CORPUS LUTEUM IN THE OVARY
CONTINUOUSLY FUNCTION CAUSING
THE ENDOMETRIUM TO THICKEN AND
VASCULAR RATHER THAN ATROPHYING
•CAUSED BY HUMAN CHORIONIC
GONADOTROPIN (HCG), A HORMONE
SECRETED BY THE TROPHOBLAST CELLS.
•LATIN WORD FOR “FALLING OFF”

23. THREE AREAS OF UTERINE
DECIDUA

24. 1. DECIDUA BASALIS -THE PART OF THE
ENDOMETRIUM THAT LIES DIRECTLY UNDER THE
EMBRYO (OR THE PORTION WHERE THE
TROPHOBLAST CELLS ESTABLISH
COMMUNICATION WITH MATERNAL
BLOOD VESSELS)
2. DECIDUA CAPSULARIS -THE PORTION OF
THE ENDOMETRIUM THAT
STRETCHES OR ENCAPSULATES THE SURFACE OF
THE TROPHOBLAST
3. DECIDUA VERA-THE REMAINING PORTION
OF THE UTERINE LINING

25. CHORIONIC
VILLI
-(11
TH
TO 12
TH
DAY) MINIATURE VILLI
THAT RESEMBLE PROBING FINGERS,
REACH OUT FROM THE SINGLE LAYER
OF CELLS INTO THE UTERINE
ENDOMETRIUM TO BEGIN
FORMATION OF THE PLACENTA.
-AT TERM, ALMOST 200 SUCH VILLI
WILL HAVE FORMED

26. TWO COVERING LAYERS:
SYNCYTIOTROPHOBLAST
OR THE SYNCYTIAL LAYER
-CELLS PRODUCES
VARIOUS PLACENTAL HORMONES, SUCH
AS HCG, SOMATOMAMMOTROPIN
(HUMAN PLACENTAL LACTOGEN [ HPL]),
ESTROGEN, AND PROGESTERONE.

27. TWO COVERING LAYERS:
CYTOTROPHOBLAST OR
LANGHANS’ LAYER
(12 DAYS’ GESTATION)
-PROTECTS THE GROWING EMBRYO
AND FETUS FROM CERTAIN INFECTIOUS
ORGANISMS
SUCH AS THE SPIROCHETE OF SYPHILIS.
THIS LAYER OF CELLS DISAPPEARS,
-DISAPPEARS AT 20TH AND 24TH

28. PLACENTA
LATIN FOR “PANCAKE,” WHICH IS
DESCRIPTIVE OF ITS SIZE AND APPEARANCE
AT TERM
ARISES OUT OF THE CONTINUING GROWTH
OF TROPHOBLAST TISSUE.
ITS GROWTH PARALLELS THAT OF THE
FETUS
15 TO 20 CM IN DIAMETER AND 2 TO 3 CM
IN DEPTH, COVERING ABOUT HALF THE
SURFACE AREA OF THE INTERNAL UTERUS

29. PLACENTAL CIRCULATION
NUTRIENTS ARE TRANSPORTED TO THE
DEVELOPING EMBRYO INFLUENCED BY MATERNAL
BLOOD PRESSURE AND THE PH OF THE FETAL AND
MATERNAL PLASMA
maternal blood begins to collect in the
intervillous spaces of the uterine
endometrium surrounding the chorionic
villi (12
TH
DAY OF PREGNANCY)
Placental osmosis from the maternal blood through the cell
layers of the chorionic villi into the villi capillaries (third week)
Note: including alcohol and nicotine

30. •NO DIRECT EXCHANGE OF BLOOD
BETWEEN THE EMBRYO AND THE MOTHER
DURING PREGNANCY. (OUTER CHORIONIC
VILLI LAYER IS ONLY ONE CELL THICK)
•AFTER THE THIRD TRIMESTER, MINUTE
BREAKS DO OCCUR AND ALLOW
OCCASIONAL FETAL CELLS TO CROSS
INTO THE MATERNAL BLOODSTREAM, AS
WELL AS FETAL ENZYMES SUCH AS ALPHA -
FETOPROTEIN (AFP) FROM THE FETAL
LIVER.

31. Increase number of chorionic villi
form an increasingly complex communication
network
with the maternal blood
Intervillous spaces grow larger
and larger, separated by a series of partitions or
Septa (cotyledons)
maternal side of the placenta look rough and
uneven

32. •100 MATERNAL UTERINE ARTERIES
•UTEROPLACENTAL BLOOD FLOW IN
PREGNANCY INCREASES FROM ABOUT 50
ML/MIN AT 10 WEEKS TO 500 TO 600
ML/MIN AT TERM.
•NO ADDITIONAL MATERNAL ARTERIES
APPEAR AFTER THE FIRST 3 MONTHS OF
PREGNANCY
•ARTERIES INCREASE IN SIZE ----------
INCREASE IN HEART RATE, TOTAL
CARDIAC OUTPUT, AND BLOOD VOLUME
INCREASE TO SUPPLY BLOOD TO THE

33. •PLACENTA WEIGHS 400 TO 600 G (1
LB) AT TERM, ONESIXTHTHE WEIGHT
OF THE BABY.

35. AMNIOTIC MEMBRANES OR AMNION
•SECOND MEMBRANE LINING THE
CHORIONIC MEMBRANE
•PURPOSE IS TO FORM THE SAC THAT
CONTAINS THE AMNIOTIC FLUID
•SMOOTH, THIN AND SHINY
STRUCTURE (CHORION LAEVE, OR
SMOOTH CHORION).
•AVASCULAR, NO NERVE SUPPLY

36. •SUPPORT AND PRODUCES AMNIOTIC
FLUID
•PRODUCES A PHOSPHOLIPID THAT
INITIATES THE FORMATION OF
PROSTAGLANDINS, WHICH CAN
CAUSE UTERINE CONTRACTIONS
AND MAY BE THE TRIGGER THAT
INITIATES LABOR.
AMNIOTIC MEMBRANES OR
AMNION

38. AMNIOTIC
FLUID
•CONSTANTLY BEING NEWLY FORMED AND
REABSORBED BY THE AMNIOTIC
•MAJOR METHOD OF ABSORPTION:
•FETUS CONTINUALLY SWALLOWS THE FLUID.
•FETAL INTESTINE, IT IS ABSORBED INTO THE FETAL
BLOODSTREAM.
•GOES TO THE UMBILICAL ARTERIES AND TO THE
PLACENTA, AND IT IS EXCHANGED ACROSS THE
PLACENTA. AT TERM, THE AMOUNT OF AMNIOTIC
FLUID HAS INCREASED
•RANGES FROM 800 TO 1200 ML.

39. AMNIOTIC
FLUID
•HYDRAMNIOS -EXCESSIVE AMNIOTIC FLUID,
OR (MORE THAN 2000 ML IN TOTAL, OR
POCKETS OF FLUID LARGER THAN 8 CM ON
ULTRASOUND)
EG.DIABETES
•FETAL URINE ADDS TO THE QUANTITY OF
THE AMNIOTIC FLUID.
•OLIGOHYDRAMNIOS -AMNIOTIC FLUID (LESS
THAN 300 ML IN TOTAL, OR NO POCKET ON
ULTRASOUND LARGER THAN 1 CM)

40. PURPOSE OF AMNIOTIC FLUID
•TO SHIELD THE FETUS AGAINST PRESSURE
OR A BLOW TO THE MOTHER’S ABDOMEN.
•PROTECTS THE FETUS FROM CHANGES IN
TEMPERATURE.
•AIDS IN MUSCULAR DEVELOPMENT BY
ALLOWING THE FETUS FREEDOM TO MOVE.
•PROTECTS THE UMBILICAL CORD FROM
PRESSURE, PROTECTING THE FETAL OXYGEN
SUPPLY.
•AMNIOTIC FLUID IS SLIGHTLY ALKALINE,
WITH A PH OF ABOUT 7.2.

41. UMBILICAL
CORD
•IS FORMED FROM THE FETAL MEMBRANES
(AMNION AND CHORION) AND PROVIDES A
CIRCULATORY PATHWAY THAT CONNECTS THE
EMBRYO TO THE CHORIONIC VILLI OF THE
PLACENTA.
•THE BULK OF THE CORD IS A GELATINOUS
MUCOPOLYSACCHARIDE CALLED WHARTON’S
JELLY, WHICH GIVES THE CORD BODY AND
PREVENTS PRESSURE ON THE VEIN AND ARTERIES.
•OUTER SURFACE IS COVERED WITH AMNIOTIC
MEMBRANE.

42. UMBILICAL
CORD
FUNCTION:
TO TRANSPORT OXYGEN AND
NUTRIENTS TO THE FETUS FROM THE
PLACENTA
TO RETURN WASTE PRODUCTS
FROM THE FETUS TO THE PLACENTA.
ABOUT 53 CM (21 IN) IN LENGTH AT
TERM
ABOUT 2 CM (3⁄4 IN) THICK.

43. UMBILICAL
CORD
•CONTAINS ONLY ONE VEIN (CARRYING BLOOD
FROM THE PLACENTAL VILLI TO THE FETUS)
•TWO ARTERIES (CARRYING BLOOD FROM THE
FETUS BACK TO THE PLACENTAL VILLI).
•IMPORTANT: ASSESSMENT AT BIRTH AND
RECORDED
•ABOUT 1% TO 5% OF INFANTS ARE BORN WITH
A CORD THAT CONTAINS ONLY A SINGLE VEIN
AND ARTERY.
•RATE OF BLOOD FLOW –RAPID (350 ML/MIN AT

44. UMBILICAL
CORD
•WALLS OF THE UMBILICAL CORD
ARTERIES ARE LINED WITH SMOOTH
MUSCLE.
•NO NERVE SUPPLY -CAN BE CUT AT
BIRTH WITHOUT DISCOMFORT TO
EITHER THE CHILD OR WOMAN.

45. PERCUTANEOUS UMBILICAL
BLOOD SAMPLING [PUBS]
•OR CORDOCENTESIS

46. QUESTION: LIZ CALHORNIS WORRIED THAT
HER BABY WILL BE BORN WITH A
CONGENITAL
HEART DISEASE. WHAT ASSESSMENT OF A
FETUS AT BIRTH IS
IMPORTANT TO HELP DETECT CONGENITAL
HEART DEFECTS?
A. ASSESSING WHETHER THE WHARTON JELLY OF
THE CORD HAS A PH HIGHER THAN 7.2.
B. ASSESSING WHETHER THE UMBILICAL CORD HAS
TWO ARTERIES AND ONE VEIN.
C. MEASURING THE LENGTH OF THE CORD TO BE
CERTAIN THAT IT IS LONGER THAN 3 FEET.
D. DETERMINING THAT THE UMBILICAL CORD IS
NOT STAINED GREEN OR YELLOW.

47. ORIGIN AND DEVELOPMENT
OF ORGAN SYSTEM
•STEM CELLS
•FIRST 4 DAYS OF LIFE, ZYGOTE CELLS ARE TERMED
TOTIPOTENT STEM CELLS (OR CELLS THAT ARE SO
UNDIFFERENTIATED THEY HAVE THE POTENTIAL
TO FORM A COMPLETE HUMAN BEING).
•8 DAYS, CELLS BEGIN TO SHOW DIFFERENTIATION,
SLATED TO BECOME SPECIFIC BODY CELLS, SUCH
AS NERVE, BRAIN, OR SKIN CELLS (PLURIPOTENT
STEM CELLS)
•BECOME MULTIPOTENTOR ARE SO SPECIFIC THAT
THEY HAVE SET A SURE COURSE TOWARD THE
BODY ORGAN THEY WILL CREATE.

48. ZYGOTE GROWTH
CEPHALOCAUDAL (HEAD-TO-TAIL)
Germ layers -arespecific tissue
layers to develop body organ systems
a. Ectoderm
b. Mesoderm
c. Endoderm

49. ORIGIN OF BODY TISSUE
Germ Layer Body Portions Formed
Ectoderm Central nervous system (brain
and
spinal cord)
Peripheral nervous system
Skin, hair, and nails
Sebaceous glands
Sense organs
Mucous membranes of the anus,
mouth, and nose
Tooth enamel
Mammary glands

50. ORIGIN OF BODY TISSUE
Germ Layer Body Portions Formed
Mesoderm Supporting structures of the body
(connective tissue, bones,
cartilage, muscle, ligaments, and
tendons)
Dentin of teeth
Upper portion of the urinary
system (kidneys and ureters)
Reproductive system
Heart
Circulatory system
Blood cells
Lymph vessels

51. ORIGIN OF BODY TISSUE
Germ Layer Body Portions Formed
Endoderm •Lining of pericardial, pleura, and
peritoneal cavities
•Lining of the gastrointestinal
tract, respiratory tract, tonsils,
parathyroid, thyroid, thymus
glands
•Lower urinary system (bladder
and urethra)

52. CONGENITAL ANOMALIES
•A FISTULA BETWEEN THE TRACHEA AND
THE ESOPHAGUS
•HEART AND KIDNEY DEFECTS
•RUBELLA INFECTION
SCREENING PROCEDURES
A RADIOGRAPHIC EXAMINATION OF
THE KIDNEY, FOR EXAMPLE, MAY BE
ORDERED FOR A CHILD BORN WITH A
HEART DEFECT.

53. ORGANOGENESIS (ORGAN
FORMATION)
•ALL ORGAN SYSTEMS ARE COMPLETE IN A
RUDIMENTARY FORM, AT 8 WEEKS’
GESTATION (THE END OF THE EMBRYONIC
PERIOD).
•THE GROWING STRUCTURE IS MOST
VULNERABLE TO INVASION BY
TERATOGENS (ANY FACTOR THAT
ADVERSELY AFFECTS THE FERTILIZED
OVUM, EMBRYO, OR FETUS, SUCH AS
CIGARETTE SMOKING)

55. TERMS USED TO DENOTE FETAL
GROWTH
Name Time Period
Ovum From ovulation to fertilization
Zygote From fertilization to implantation
Embryo From implantation to 5–8 weeks
Fetus From 5–8 weeks until term
Conceptus Developing embryo or fetus and placental
structures throughout pregnancy
Age of viabilityThe earliest age at which fetuses could
survive if they were born at that time,
generally accepted as 20 weeks, or
fetuses weighing more than 500 g

56. CARDIOVASCULAR SYSTEM
•6
TH
TO 7
TH
WEEK –DEVELOPS SEPTUM
THAT DIVIDES THE HEART INTO
CHAMBERS
-HEART VALVES BEGIN TO DEVELOP
•10
TH
TO 12
TH
WEEK -THE HEARTBEAT
MAY BE HEARD WITH A DOPPLER
INSTRUMENT
•HEART RATE OF A FETUS IS AFFECTED BY
OXYGEN LEVEL, ACTIVITY, AND
CIRCULATING BLOOD VOLUME

60. RESPIRATORY SYSTEM
•THIRD WEEK -THE RESPIRATORY AND DIGESTIVE TRACTS
EXIST AS A SINGLE TUBE. LIKE ALL BODY TUBES, INITIALLY
THIS FORMS AS A SOLID STRUCTURE, WHICH THEN
CANALIZES (HOLLOWS OUT).
•END OF THE FOURTH WEEK, A SEPTUM BEGINS TO DIVIDE
THE ESOPHAGUS FROM THE TRACHEA. LUNG BUDS APPEAR
ON THE TRACHEA.
•SEVENTH WEEK OF LIFE, THE DIAPHRAGM DOES NOT
COMPLETELY DIVIDE THE THORACIC CAVITY FROM THE
ABDOMEN. THIS CAUSES LUNG BUDS TO EXTEND DOWN
INTO THE ABDOMEN, REENTERING THE CHEST ONLY AS THE
CHEST’S LONGITUDINAL DIMENSION INCREASES AND THE
DIAPHRAGM BECOMES COMPLETE (AT THE END OF THE
SEVENTH WEEK).
•EG.DIAPHRAGMATIC HERNIA (DIAPHRAGM FAILS TO CLOSE
COMPLETELY)

61. DIAPHRAGMATIC HERNIA

62. •24TH AND 28TH WEEKS -ALVEOLI AND
CAPILLARIES BEGIN TO FORM
•3 MONTHS-SPONTANEOUS RESPIRATORY
PRACTICE MOVEMENTS
•SPECIFIC LUNG FLUID WITH A LOW SURFACE
TENSION AND LOW VISCOSITY FORMS IN ALVEOLI
TO AID IN EXPANSION OF THE ALVEOLI AT BIRTH;
IT IS RAPIDLY ABSORBED AFTER BIRTH.
•24TH WEEK -SURFACTANT, A PHOSPHOLIPID
SUBSTANCE, IS FORMED AND EXCRETED BY THE
ALVEOLAR CELLS
RESPIRATORY SYSTEM

63. TWO COMPONENTS 0F
SURFACTANT
LECITHIN (L) AND SPHINGOMYELIN (S).
•SPHINGOMYELIN IS THE CHIEF COMPONENT -EARLY IN THE
FORMATION OF SURFACTANT.
•ABOUT 35 WEEKS -A SURGE IN THE PRODUCTION OF
LECITHIN, WHICH THEN BECOMES THE CHIEF COMPONENT
BY A RATIO OF 2:1.
-AS A FETUS PRACTICES BREATHING MOVEMENTS,
SURFACTANT MIXES WITH AMNIOTIC FLUID.
•PRIMARY TEST OF FETAL MATURITY
•WHETHER LECITHIN OR SPHINGOMYELIN IS THE DOMINANT
COMPONENT BY AMNIOCENTESIS TECHNIQUE
•RESPIRATORY DISTRESS SYNDROME, A SEVERE BREATHING
DISORDER, CAN DEVELOP IF THERE IS LACK OF SURFACTANT
OR IT HAS NOT CHANGED TO ITS MATURE FORM AT BIRTH

64. LIZ CALHORNASKS YOU WHY HER
DOCTOR IS SO CONCERNED ABOUT
WHETHER HER FETUS IS PRODUCING
SURFACTANT. YOUR BEST ANSWER
WOULD BE:
A. SURFACTANT KEEPS LUNGS FROM COLLAPSING ON
EXPIRATION AND SO AIDS NEWBORN BREATHING.
B. SURFACTANT IS PRODUCED BY THE FETAL LIVER, SO
ITS PRESENCE REVEALS LIVER MATURITY.
C. SURFACTANT IS THE PRECURSOR TO IGM ANTIBODY
PRODUCTION, SO IT PREVENTS INFECTION.
D. SURFACTANT REVEALS MATURE KIDNEY FUNCTION,
AS IT IS PRODUCED BY KIDNEY GLOMERULI.

65. NERVOUS SYSTEM
•THIRD AND FOURTH WEEKS (POSSIBLY BEFORE THE
WOMAN EVEN REALIZES SHE IS PREGNANT, ACTIVE
FORMATION OF THE NERVOUS SYSTEM AND SENSE
ORGANS HAS ALREADY BEGUN)
•A NEURAL PLATE (A THICKENED PORTION OF THE
ECTODERM) IS APPARENT
•THE TOP PORTION -DIFFERENTIATES INTO THE
NEURAL TUBE, WHICH WILL FORM THE CENTRAL
NERVOUS SYSTEM (BRAIN AND SPINAL CORD)
•THE NEURAL CREST, WHICH WILL DEVELOP INTO THE
PERIPHERAL NERVOUS SYSTEM.
•ALL PARTS OF THE BRAIN (CEREBRUM, CEREBELLUM,
PONS, AND MEDULLA OBLONGATA) FORM IN UTERO

66. NERVOUS SYSTEM
•5 OR 6 YEARS OF AGE. (BRAIN MATURITY)
•THE EYE AND INNER EAR DEVELOP AS
PROJECTIONS OF THE ORIGINAL NEURAL
TUBE.
•24 WEEKS, THE EAR IS CAPABLE OF
RESPONDING TO SOUND; EYES EXHIBIT A
PUPILLARY REACTION,
•EIGHTH WEEK-BRAIN WAVES CAN BE
DETECTED ON AN
ELECTROENCEPHALOGRAM (EEG)
•EG.

67. ENDOCRINE SYSTEM
•FETAL ADRENAL GLANDS SUPPLY A
PRECURSOR NECESSARY FOR ESTROGEN
SYNTHESIS BY THE PLACENTA.
•THE FETAL PANCREAS PRODUCES INSULIN
NEEDED BY THE FETUS (INSULIN IS ONE OF
THE FEW SUBSTANCES THAT DOES NOT
CROSS THE PLACENTA FROM THE MOTHER
TO THE FETUS).
•THE THYROID AND PARATHYROID GLANDS
PLAY VITAL ROLES IN FETAL METABOLIC
FUNCTION AND CALCIUM BALANCE.

68. DIGESTIVE SYSTEM
•FOURTH WEEK -DIGESTIVE TRACT
SEPARATES FROM THE RESPIRATORY AND
GROWS RAPIDLY
•THE TRACT CANALIZES (HOLLOWS OUT)
TO BECOME PATENT.
•EG.ATRESIA (BLOCKAGE) OR STENOSIS
(NARROWING)
•THE PROLIFERATION OF CELLS SHED IN
THE SECOND RECANALIZATION FORMS
THE BASIS FOR MECONIUM.

69. •SIXTH WEEK -THE INTESTINE BECOMES TOO LARGE
TO BE CONTAINED BY THE ABDOMEN. A PORTION OF
THE INTESTINE,
•10TH WEEK-GUIDED BY THE VITELLINE MEMBRANE (A
PART OF THE YOLK SAC), IS PUSHED INTO THE BASE
OF THE UMBILICAL CORD WHEN THE ABDOMINAL
CAVITY HAS GROWN LARGE ENOUGH TO
ACCOMMODATE THE INTESTINAL MASS
•THE INTESTINE RETURNS TO THE ABDOMINAL CAVITY,
AND MUST ROTATE 180 DEGREES.
•FAILURE TO DO SO CAN RESULT IN INADEQUATE
MESENTERY ATTACHMENTS
•EG.VOLVULUS OF THE INTESTINE IN THE NEWBORN.
DIGESTIVE SYSTEM

70. GASTROSCHISIS -
OCCURS WHEN THE
ORIGINAL MIDLINE
FUSION THAT
OCCURRED AT THE
EARLY CELL STAGE IS
INCOMPLETE
DIGESTIVE SYSTEM
Omphalocele -
intestine remains
the abdomen in
the base of the
cord.

71. MECKEL’S
DIVERTICULUM -IF
THE VITELLINE DUCT
DOES NOT ATROPHY
AFTER RETURN OF THE
INTESTINES, A (A
POUCH OF INTESTINAL
TISSUE) CAN RESULT.
DIGESTIVE SYSTEM

72. MECONIUM
•16TH WEEK -A COLLECTION OF
CELLULAR WASTES, BILE, FATS,
MUCOPROTEINS,
MUCOPOLYSACCHARIDES, AND PORTIONS
OF THE VERNIX CASEOSA, ACCUMULATES
IN THE INTESTINES
•IS STICKY IN CONSISTENCY AND APPEARS
BLACK OR DARK GREEN (OBTAINING ITS
COLOR FROM BILE PIGMENT).

73. QUESTION:
TRUE OR FALSE
GASTROINTESTINAL TRACT
IS STERILE BEFORE BIRTH
ANSWER: TRUE

74. •VITAMIN K IS SYNTHESIZED BY THE ACTION OF
BACTERIA IN THE INTESTINES, VITAMIN K LEVELS ARE
LOW IN THE NEWBORN.
•LIVERIS ACTIVE THROUGHOUT GESTATION
FUNCTION:
•AS A FILTER BETWEEN THE INCOMING BLOOD
AND THE FETAL CIRCULATION
•AS A DEPOSIT SITE FOR FETAL STORES SUCH AS
IRON AND GLYCOGEN, BUT IS STILL IMMATURE
AT BIRTH. ------HYPOGLYCEMIA AND
HYPERBILIRUBINEMIA IN FIRST 24 HOURS AFTER
BIRTH.
•DOES NOT PREVENT RECREATIONAL DRUGS OR
ALCOHOL INGESTED BY THE MOTHER FROM

75. MUSCULOSKELETAL SYSTEM
•12TH WEEK-BONE OSSIFICATION
CONTINUES ALL THROUGH FETAL
LIFE AND ACTUALLY UNTIL
ADULTHOOD.

76. REPRODUCTIVE SYSTEM
•8 WEEKS -A CHILD’S SEX BY CHROMOSOMAL
ANALYSIS.
•SIXTH WEEK -GONADS (OVARIES OR TESTES) FORM.
•IF TESTES FORM, TESTOSTERONE IS SECRETED,
APPARENTLY INFLUENCING THE SEXUALLY NEUTRAL
GENITAL DUCT TO FORM OTHER MALE ORGANS
(MATURITY OF THE WOLFFIAN, OR MESONEPHRIC, DUCT).
•IN THE ABSENCE OF TESTOSTERONE SECRETION, FEMALE
ORGANS WILL FORM (MATURATION OF THE MÜLLERIAN,
OR PARAMESONEPHRIC, DUCT).
•EG.WOMAN TAKING ANDROGEN OR AN ANDROGEN -
LIKE SUBSTANCE
-IF DEFICIENT TESTOSTERONE IS SECRETED BY
THE TESTES, BOTH THE MÜLLERIAN(FEMALE) DUCT
AND THE MALE (WOLFFIAN) DUCT COULD DEVELOP
(PSEUDO-HERMAPHRODITISM, OR INTERSEX).

77. •TESTES FIRST FORM IN THE
ABDOMINAL CAVITY AND DO NOT
DESCEND INTO THE SCROTAL SAC
UNTIL THE 34TH TO 38TH WEEK.
•EG.MALE PRETERM INFANTS ARE
BORN WITH UNDESCENDED TESTES.
= POOR SPERM PRODUCTION AND
TESTICULAR CANCER

78. URINARY SYSTEM
•END OF FOURTH WEEK -RUDIMENTARY KIDNEYS
ARE PRESENT BUT NOT ESSENTIAL FOR LIFE
BEFORE BIRTH BECAUSE THE PLACENTA CLEARS
THE FETUS OF WASTE PRODUCTS.
•12TH WEEK-URINE IS FORMED AND IS EXCRETED
INTO THE AMNIOTIC
FLUID BY THE 16TH WEEK OF GESTATION.
•AT TERM, FETAL URINE IS BEING EXCRETED AT
THE RATE OF 500 ML/DAY.

79. INTEGUMENTARY SYSTEM
•APPEARS THIN AND ALMOST
TRANSLUCENT
•36 WEEKS -SUBCUTANEOUS FAT BEGINS
TO BE DEPOSITED
•LANUGO-SOFT DOWNY HAIRS COVERING
THE SKIN THAT SERVE AS INSULATION TO
PRESERVE WARMTH IN UTERO
•VERNIX CASEOSA –CREAM CHEESE–LIKE
SUBSTANCE, WHICH IS IMPORTANT FOR
LUBRICATION AND FOR KEEPING THE SKIN
FROM MACERATING IN UTERO.

80. IMMUNE SYSTEM
•20TH WEEK -IMMUNOGLOBULIN G (IGG)
MATERNAL ANTIBODIES CROSS THE PLACENTA
INTO THE FETUS
•24TH WEEK -GIVE A FETUS TEMPORARY PASSIVE
IMMUNITY AGAINST DISEASES FOR WHICH THE
MOTHER HAS ANTIBODIES.
EG.POLIOMYELITIS, RUBELLA (GERMAN MEASLES),
RUBEOLA (REGULAR MEASLES), DIPHTHERIA,
TETANUS, INFECTIOUS PAROTITIS (MUMPS),
HEPATITIS B, AND PERTUSSIS (WHOOPING COUGH).
•LITTLE OR NO IMMUNITY TO THE HERPES VIRUS
(THE VIRUS OF CHICKENPOX, COLD SORES, AND
GENITAL HERPES)

81. IMMUNE SYSTEM
•A FETUS IS CAPABLE OF ACTIVE ANTIBODY
PRODUCTION LATE IN PREGNANCY.
EG.HOWEVER, INFANTS WHOSE MOTHERS
HAVE HAD AN INFECTION SUCH AS
RUBELLA DURING PREGNANCY TYPICALLY
HAVE ACTIVE IGM ANTIBODIES TO RUBELLA
IN THEIR BLOOD SERUM AT BIRTH.
(+ IGA AND IGM –EXPOSURE TO A
DISEASE ANTIBODIES CANNOT CROSS THE
PLACENTA)

83. •END OF 4TH GESTATIONAL WEEK
-THE HUMAN EMBRYO IS A GROUP
OF RAPIDLY GROWING CELLS BUT DOES
NOT YET RESEMBLE A HUMAN BEING.
• LENGTH: 0.75–1 CM
• WEIGHT: 400 MG
• SPINAL CORD IS FORMED AND FUSED AT
THE MIDPOINT.
• LATERAL WINGS THAT WILL FORM THE
BODY ARE FOLDED FORWARD TO FUSE AT
THE MIDLINE.

84. END OF 4TH GESTATIONAL WEEK
• HEAD FOLDS FORWARD AND BECOMES
PROMINENT, REPRESENTING ABOUT ONE -
THIRD OF THE ENTIRE STRUCTURE.
• BACK IS BENT SO THAT THE HEAD ALMOST
TOUCHES THE TIP OF THE TAIL.
• RUDIMENTARY HEART APPEARS AS A
PROMINENT BULGE ON THE ANTERIOR
SURFACE.
• ARMS AND LEGS ARE BUDLIKE STRUCTURES.
• RUDIMENTARY EYES, EARS, AND NOSE ARE
DISCERNIBLE.

85. BY 8TH WEEKS:
•LENGTH: 2.5 CM (1 IN)
•WEIGHT: 20 GRAMS
•ORGANOGENESIS IS COMPLETE.
•THE HEART, WITH A SEPTUM AND VALVES, IS
BEATING RHYTHMICALLY.
•HEAD IS LARGER THAN TRUNK. FACIAL FEATURES
ARE DEFINITELY DISCERNIBLE. CENTRAL
HEMISPHERES APPEAR, FACE ELONGATES AND
EYELID FOLDS HAVE DEVELOPED BUT EYES ARE STILL
FAR APART. FLAT NOSE AND RECOGNIZABLE MOUTH
ARE EVIDENT. EXTERNAL EARS LOOK SIMILAR TO
FINAL APPEARANCE.

86. BY 8TH WEEKS:
•ARMS, LEGS, FINGERS AND TOES ARE DISTINCT.
•HEART AND LIVER ARE PROMINENT.
•EXTERNAL GENITALIA ARE FORMING, BUT SEX IS
NOT YET DISTINGUISHABLE BY SIMPLE
OBSERVATION.
• THE PRIMITIVE TAIL IS REGRESSING.
• THE ABDOMEN BULGES FORWARD BECAUSE
THE FETAL INTESTINE IS GROWING SO RAPIDLY.
• AN ULTRASOUND SHOWS A GESTATIONAL
SAC, DIAGNOSTIC OF PREGNANCY

87. BY 12TH WEEKS:(FIRST TRIMESTER)
•LENGTH: 7–8 CM
•WEIGHT: 45 GRAMS
•NAIL BEDS ARE FORMING ON FINGERS AND
TOES.
•SPONTANEOUS MOVEMENTS ARE POSSIBLE BUT
TOO FAINT TO BE FELT BY THE MOTHER.
•INTESTINAL VILLI FORM.
•BLADDER AND URETHRA SEPARATE FROM
RECTUM. KIDNEYS BEGIN TO SECRETE URINE
BUT MAY NOT YET BE EVIDENT IN AMNIOTIC
FLUID.

88. BY 12TH WEEKS:(FIRST TRIMESTER)
•BRONCHIOLES BRANCH AND PLEURAL AND
PERICARDIAL CAVITIES APPEAR. LUNGS ASSUME
DEFINITIVE SHAPE.
•THYROID AND PANCREAS BEGIN TO SECRETE
HORMONES.
•SEX IS DISTINGUISHABLE BY OUTWARD APPEARANCE.
•BONE OSSIFICATION CENTERS BEGIN TO FORM.
•SOME REFLEXES, SUCH AS THE BABINSKI REFLEX, ARE
PRESENT.
•TOOTH BUDS ARE PRESENT.
•THE HEARTBEAT IS AUDIBLE THROUGH DOPPLER
TECHNOLOGY.

89. BY 16TH WEEKS:
•LENGTH: 10–17 CM
•WEIGHT: 55–120 GRAMS
•FETAL HEART SOUNDS ARE AUDIBLE
BY AN ORDINARY STETHOSCOPE.
•LANUGO IS WELL FORMED.
•JOINT CAVITIES ARE PRESENT.
•BILE IS SECRETED.
•INTESTINES ASSUME NORMAL
POSITION, MECONIUM PRESENT.

90. END OF 16TH WEEKS:
•KIDNEYS IN PROPER POSITION. TESTES
BEGIN TO DESCEND INTO INGUINAL
CANAL. MORE HUMAN -LIKE APPEARANCE.
•LIVER AND PANCREAS ARE FUNCTIONING.
•FETUS ACTIVELY SWALLOWS AMNIOTIC
FLUID, DEMONSTRATING AN INTACT BUT
UNCOORDINATED SWALLOWING REFLEX;
URINE IS PRESENT IN AMNIOTIC FLUID.
•SEX CAN BE DETERMINED BY
ULTRASOUND.

91. END OF 20TH WEEKS:
•LENGTH: 25 CM
•WEIGHT: 223 G
•BRAIN GROSSLY FORMED.
•SPINAL CORD MYELINIZATION BEGINS.
•LANUGO AND VERNIX CASEOSA BEGIN
TO FORM.
•SPONTANEOUS FETAL MOVEMENTS
CAN BE SENSED BY THE MOTHER.

92. END OF 20TH WEEKS:
•ANTIBODY PRODUCTION IS POSSIBLE.
•THE HAIR FORMS ON THE HEAD, EXTENDING TO
INCLUDE EYEBROWS.
•MECONIUM IS PRESENT IN THE UPPER INTESTINE.
•BROWN FAT, A SPECIAL FAT THAT WILL AID IN
TEMPERATURE REGULATION AT BIRTH, BEGINS TO BE
FORMED BEHIND THE KIDNEYS, STERNUM, AND
POSTERIOR NECK.
•PASSIVE ANTIBODY TRANSFER FROM MOTHER TO FETUS
BEGINS.
•DEFINITE SLEEPING AND ACTIVITY PATTERNS ARE
DISTINGUISHABLE
•(THE FETUS HAS DEVELOPED BIORHYTHMS THAT WILL

93. END OF 24TH WEEKS:
•LENGTH: 28–36 CM
•WEIGHT: 550 G
•MECONIUM IS PRESENT AS FAR AS THE
RECTUM.
•EYES ARE STRUCTURALLY COMPLETE.
EYEBROWS AND EYELASHES BECOME
WELL DEFINED. EYELIDS, PREVIOUSLY
FUSED SINCE THE 12TH WEEK, NOW
OPEN. PUPILS ARE CAPABLE OF
REACTING TO LIGHT.

94. END OF 24TH WEEKS:
•ACTIVE PRODUCTION OF LUNG
SURFACTANT BEGINS.
•EXTERNAL GENITALIA DISCERNIBLE.
•SKIN RED AND WRINKLED.
AGE OF VIABILITY (EARLIEST AGE AT WHICH
FETUSES COULD SURVIVE IF BORN AT THAT
TIME), IF THEY ARE CARED FOR AFTER BIRTH
IN A MODERN INTENSIVE CARE FACILITY.
HEARING CAN BE DEMONSTRATED BY
RESPONSE TO SUDDEN SOUND.

95. END OF 28TH WEEKS:
•LENGTH: 35–38 CM
•WEIGHT: 1200 G
•FACE MATURES.
•LUNG ALVEOLI BEGIN TO MATURE, AND
SURFACTANT CAN BE DEMONSTRATED
IN AMNIOTIC FLUID.
•TESTES BEGIN TO DESCEND INTO THE
SCROTAL SAC FROM THE LOWER
ABDOMINAL CAVITY.

96. END OF 28TH WEEKS:
•TESTES BEGIN TO DESCEND INTO THE
SCROTAL SAC FROM THE LOWER
ABDOMINAL CAVITY.
•THE BLOOD VESSELS OF THE RETINA
ARE FORMED BUT THIN AND EXTREMELY
SUSCEPTIBLE TO DAMAGE FROM HIGH
OXYGEN CONCENTRATIONS (AN
IMPORTANT CONSIDERATION WHEN
CARING FOR PRETERM INFANTS WHO
NEED OXYGEN).

97. END OF 32ND WEEKS:
•LENGTH: 38–43 CM
•WEIGHT: 1600 G
•SUBCUTANEOUS FAT BEGINS TO BE
DEPOSITED (THE FORMER STRINGY,
“LITTLE OLD MAN” APPEARANCE IS LOST).
•HAIR EVIDENT. STILL COVERED WITH
VERNIX CASEOSA.
•CAN TURN HEAD SIDE TO SIDE.
RESPONDS BY MOVEMENT TO SOUNDS
OUTSIDE THE MOTHER’S BODY.

98. END OF 32ND WEEKS:
•ACTIVE MORO REFLEX IS PRESENT.
•SKIN BEGINS TO SMOOTH OUT.
•IRON STORES, WHICH PROVIDE IRON FOR
THE TIME DURING WHICH THE NEONATE
WILL INGEST ONLY MILK AFTER BIRTH, ARE
BEGINNING TO BE DEVELOPED.
•FINGERNAILS GROW TO REACH THE END OF
FINGERTIPS.
•CHANCES OF SURVIVAL OUTSIDE UTERO
INCREASE.

99. END OF 36TH WEEKS:
•LENGTH: 42–48 CM
•WEIGHT: 1800–2700 G (5–6 LB)
•LANUGO BEGINS TO DISAPPEAR.
•SUBCUTANEOUS FAT CONTINUES TO
INCREASE.
•ELONGATION OF SPINAL CORD ALMOST
COMPLETE.
•BODY STORES OF GLYCOGEN, IRON,
CARBOHYDRATE, AND CALCIUM ARE
DEPOSITED.

100. END OF 36TH WEEKS:
•SOLE OF THE FOOT HAS ONLY ONE
OR TWO CRISSCROSS CREASES,
COMPARED WITH THE FULL
CRISSCROSS PATTERN THAT WILL
BE EVIDENT AT TERM.
•MOST BABIES TURN INTO A VERTEX
(HEAD DOWN) PRESENTATION
DURING THIS MONTH.
•GOOD CHANCE OF SURVIVAL.

101. END OF 40TH WEEKS:
•LENGTH: 48–52 CM (CROWN TO RUMP,
35–37 CM)
•WEIGHT: 3000 G (7–7.5 LB)
•BABY IS FULL TERM.
•BOTH TESTES HAVE DESCENDED
IN THE MALE.
•LANUGO HAS DISAPPEARED.
•ALL ORGAN SYSTEMS HAVE DEVELOPED.
•LECITHIN-SPHINGOMYELIN (L-S) RATIO IS
2:1.

102. END OF 40TH WEEKS:
•FETUS KICKS ACTIVELY, HARD ENOUGH TO
CAUSE THE MOTHER CONSIDERABLE
DISCOMFORT.
•FETAL HEMOGLOBIN BEGINS ITS CONVERSION
TO ADULT HEMOGLOBIN. THE CONVERSION IS
SO RAPID THAT, AT BIRTH, ABOUT 20% OF
HEMOGLOBIN WILL BE ADULT IN CHARACTER.
•VERNIX CASEOSA IS FULLY FORMED.
•FINGERNAILS EXTEND OVER THE FINGERTIPS.
•CREASES ON THE SOLES OF THE FEET COVER
AT LEAST TWO THIRDS OF THE SURFACE.

103. 1. A CLIENT WHO’S 16 WEEK PREGNANT
ATTENDS A CLASS ON FETAL DEVELOPMENT
AS PART OF A CHILDBIRTH EDUCATION
PROGRAM. THE NURSE ANTICIPATES THAT AT
16 WEEKS GESTATION, THE CLIENT’S FETUS
WILL:
A. BE ABLE TO SUCK AND SWALLOW
B. OPEN THE EYES
C. HAVE AUDIBLE HEART SOUNDS
D. HAVE OPEN NOSTRILS

104. 2. WHICH OF THE FOLLOWING FUNCTIONS
WOULD THE NURSE EXPECT TO BE
UNRELATED TO THE PLACENTA?
A. PRODUCTION OF ESTROGEN AND
PROGESTERONE
B. DETOXIFICATION OF SOME DRUGS AND
CHEMICALS
C. EXCHANGE SITE FOR FOOD, GASES, AND
WASTE
D. PRODUCTION OF MATERNAL ANTIBODIES

105. MEDICAL TERMINOLOGIES
•TERATOGENS-ANY SUBSTANCE THAT COULD BE
HARMFUL TO A FETUS.
•LANUGO-FINE, SOFT HAIR, ESPECIALLY THAT
WHICH COVERS THE BODY AND LIMBS OF A HUMAN
FETUS OR NEWBORN.
•VERNIX CASEOSA, ALSO KNOWN ASVERNIX -IS THE
WAXY OR CHEESE-LIKE WHITE SUBSTANCE FOUND
COATING THE SKIN OF NEWBORN HUMAN BABIES. IT
IS PRODUCED BY DEDICATED CELLS AND IS
THOUGHT TO HAVE SOME PROTECTIVE ROLES
DURING FETAL DEVELOPMENT AND FOR A FEW
HOURS AFTER BIRTH.

106. FETAL HEART RATE
•120 TO 160
BEATS PER MINUTE
THROUGHOUT
PREGNANCY.
•10TH TO 11TH
WEEK OF
PREGNANCY BY
THE USE OF AN
ULTRASONIC
DOPPLER
TECHNIQUE

107. DIAGNOSTIC TESTS
RHYTHM STRIP TESTING -MEANS
ASSESSMENT OF THE FETAL HEART
RATE FOR WHETHER A GOOD BASELINE
RATE AND A DEGREE OF VARIABILITY
ARE PRESENT. F
oSEMI-FOWLER’S POSITION
oATTACH AN EXTERNAL FETAL HEART RATE
MONITOR ABDOMINALLY RECORD THE
FETAL HEART RATE FOR 20 MINUTES.

108. DIAGNOSTIC TESTS
RHYTHM STRIP TESTING
•BASELINE READING REFERS TO THE AVERAGE RATE OF
THE FETAL HEARTBEAT PER MINUTE.
•VARIABILITY REFERS TO SMALL CHANGES IN RATE THAT
OCCUR IF THE FETAL PARASYMPATHETIC AND
SYMPATHETIC NERVOUS SYSTEMS ARE RECEIVING
ADEQUATE OXYGEN AND NUTRIENTS.
•ABSENT (NONE APPARENT);
•MINIMAL (EXTREMELY SMALL FLUCTUATIONS);
•MODERATE (AMPLITUDE RANGE OF 6–25 BEATS PER
MINUTE);
•MARKED (AMPLITUDE RANGE OVER 25 BEATS PER
MINUTE

109. The upper strip signifies heart rate; the lower strip
indicates uterine activity. Arrows signal fetal movement.

110. NONSTRESS TESTING
•MEASURES THE RESPONSE OF THE FETAL HEART RATE TO
FETAL MOVEMENT.
•ATTACH BOTH A FETAL HEART RATE AND A UTERINE
CONTRACTION MONITOR.
•INSTRUCT A WOMAN TO PUSH A BUTTON ATTACHED TO
THE MONITOR (SIMILAR TO A CALL BELL) WHENEVER SHE
FEELS THE FETUS MOVE. (DARK MARK ON THE PAPER
TRACING)
•WHEN THE FETUS MOVES, THE FETAL HEART RATE SHOULD
INCREASE ABOUT 15 BEATS PER MINUTE AND REMAIN
ELEVATED FOR 15 SECONDS.
•DECREASE -AS THE FETUS QUIETS. = IF NO INCREASE IN
BEATS PER MINUTE IS NOTICEABLE ON FETAL MOVEMENT,
POOR OXYGEN PERFUSION OF THE FETUS IS SUGGESTED.

111. NONSTRESS TESTING
•DONE FOR 10 TO 20 MINUTES.
•REACTIVE -IF TWO ACCELERATIONS OF FETAL
HEART RATE (BY 15 BEATS OR MORE) LASTING
FOR 15 SECONDS OCCUR AFTER MOVEMENT
WITHIN THE CHOSEN TIME PERIOD.
•NONREACTIVE -IF NO ACCELERATIONS OCCUR
WITH THE FETAL MOVEMENTS.
•IF NO FETAL MOVEMENT OCCURS OR IF THERE IS
LOW SHORT-TERM FETAL HEART RATE VARIABILITY
(LESS THAN 6 BEATS PER MINUTE) THROUGHOUT
THE TESTING PERIOD.

112. •IF A 20-MINUTE PERIOD PASSES WITHOUT ANY
FETAL MOVEMENT, IT MAY MEAN ONLY THAT THE
FETUS IS SLEEPING.
•OTHER REASONS FOR LESSENED VARIABILITY:
•ARE MATERNAL SMOKING
•DRUG USE
•HYPOGLYCEMIA.
•GIVE THE WOMAN AN ORAL CARBOHYDRATE SNACK
SUCH AS ORANGE JUICE
•STIMULATED BY A LOUD SOUND
•NONINVASIVE PROCEDURES
•IF NONREACTIVE –DO CONTRACTION STRESS TEST
OR A BIOPHYSICAL PROFILE

113. END