Conception/Obstetrics Nursing

CONCEPTION

THE PROCESS OF CONCEPTION

OVUM The ovum or egg cell is the female sex cell or

gamete OOGENESIS refers to the development and

maturation of ovum The ovum is regularly released by the ovary

through the process of OVULATION The egg cell has a lifespan of 24 hours, it can only

be fertilized within this period. The ovum has two protective covering; the outer

layer and the inner layer.

Zona Pellucida

Zona Pellucida

Corona RadiataCorona Radiata

THE PROCESS OF CONCEPTION

SPERM The sperm cell or spermatozoa is the male sex

cell or gamete SPERMATOGENESIS is the process of maturation

of sperm. It takes about days for sperm cell to attain maturity

It has three parts a HEAD, NECK,TAIL The sperm has a lifespan of 48 to 72 hours. The

sperm most be in the genital tract 2 to 6 hours before they can fertilize the egg to give time for CAPACITATION to occur.There are two type of sperm

cell;Gynosperm Androsperm

INSEMINATION

The deposition of sperm cell in the female genital tract that occurs during sexual intercourse.

The sperm swims so fast that within 90 seconds it reaches the uterus and in the fallopian tube within 5 minutes after deposition.

FERTILIZATION

• When the sperm cell reaches the uterus its head undergoes structural changes called capacitation.

FERTILIZATION

CHROMOSOME AND GENES The heredity and characteristics of a

person are found inside the cells nucleus in the form of chromosomes. Each strands of chromosomes is made up of thousands of genes that are composed of protein substance called DNA and RNA.

CHROMOSOME AND GENES

TWO TYPES OF CELLS FOUND IN HUMANS:

• BODY CELLS or somatic cells contain 46 chromosomes referred to as the diploid number . (Mitosis)

• SEX CELLS or gametes are the OVUM and SPERM cell. These cells divides by MEOSIS.

CHROMOSOME AND GENES

Each chromosomes is made up of a long thin thread of DNA that is coiled like a ball of string.

Like chromosomes GENES are inherited in pairs one from each parents. It is estimated that there are about 30,000 gene pair in each pair that makes up the person’s genetic blueprint.

MALE KARYOTYPE

FEMALE KARYOTYPE

Selected Examples of Single Gene Disorder

DISORDER OCCURRENCES

INHERITANCE

DESCRIPTION

ALBINISM 1:15,000-1:40,000

Autosomal Recessive

Melanin lacking in skin, hair and eyes,nystagmus

and photophobia

CYSTIC FIBROSIS 1:2000-1:2500

Autosomal Recessive

Abnormal exocrine gland function with pancreatic

insufficiency , chronic pulmonary disease,

excessive chloride in sweat

DUCHENNE MUSCULAR DYSTROPHY

1:3000-1:5000 males

X linked Recessive

Progressive muscular weakness atrophy

contractures, respiratory insufficiency and eventually death

HEMOPHILIA A 1:2500-1:4000 males

X linked Recessive

Coagulation disorder due to deficiency of factor VIII

HEMOPHILIA B 1:4000-1:7000 males

X linked Recessive

Coagulation disorder due to deficiency of factor IX

POLYDACTYLY 1:100-1:300 X Linked Dominant

Extra digits in hand s and feet

Assessment for the Presence of Genetic Defects

HistoryPhysical Assessment

Assessment for the Presence of Genetic Defects

KaryotypingChorionic Villi SamplingAmniocentesisPercutaneous Umbilical SamplingAlfa Fetoprotein AnalysisSonographyFetoscopy

Fertilization,Implantation,Fetal Development


Fertilization is the union of the ovum and a spermatozoon.(conception, impregnation or fecundation)

Name Time Period

Ovum From ovulation to fertilization

Zygote From fertilization to implantation

Embryo From fertilization to 5 to 8 weeks

Fetus From 8 weeks until term

Conceptus Developing embryo or fetus and placental structures throughout term


•This is the first cell of the human body formed from the fertilization of sperm and ovum.•The zygote journey from the fallopian tube to the uterus for a period of 3-4 days.






• BLASTOCYST is a ball like structure composed of inner cell embryonic disc or BLASTOCOELE and an outer layer of rapidly developing cells called TROPOBLAST.


• The Blastocyst remain free floating in the The Blastocyst remain free floating in the uterine cavity for 3 to 4days. It implants in the uterine cavity for 3 to 4days. It implants in the endometrium approximately 6 to 7 days after endometrium approximately 6 to 7 days after fertilization.fertilization.

• The ideal site for implantation is the FUNDAL The ideal site for implantation is the FUNDAL PORTION. 2/3 of the cases implant at the upper PORTION. 2/3 of the cases implant at the upper post. Uterine and 1/3 anterior surface of uterine post. Uterine and 1/3 anterior surface of uterine portionportion..


• TROPOBLAST gives rise to the PLACENTA, FETAL MEBRANE,UMBILICAL CORD and AMNIOTIC FLUID.

» Absorbs nutrients from the endometrium

» Secretes the hormone HCG


• BLASTOCOELE or embryonic disc gives rise to the three primary germ layer.

» Ectoderm» Endoderm» Mesoderm


DECIDUA:ENDOMETRIUM OF PREGNANCY

• After implantation the endometrium is now referred to as the DECIDUA

– The most ideal site for implantation

– Prevent infection coming from the vagina and cervix

– Hormone production; Prolactin, Relaxin, CRH, Growth hormones, Prostaglandin, Oxytocin and Endothelin-1

DECIDUA:ENDOMETRIUM OF PREGNANCY

Composed of three layers:• Decidua Parietalis located

under the decidua basalis• Decisua Basalis layer where

implantation takes place. This will also form the maternal side of the placenta.

• Decidua Capsularis enclose the blastocyst after implantation.



• During the 11During the 11thth to 12 to 12thth day when day when implantation is achieved. The tropoblast implantation is achieved. The tropoblast layer of the blastocyst begins to mature layer of the blastocyst begins to mature rapidly. That bring the development of a rapidly. That bring the development of a fingers or probes that reach out from a fingers or probes that reach out from a single layer of cell known as chorionic villisingle layer of cell known as chorionic villi


Fetal MembraneFetal MembraneThe fetal membrane encloses the fetus

and the amniotic fluid and protects the fetus against ascending bacterial infection as long it is not ruptured.

CHORIONIC MEMBRANE is a thick, opaque and friable membrane that comes in contact with the decidua and is attached at the margin of the placenta.

AMNIOTIC MEMBRANE it is a smooth, thin, tough and translucent membrane that is directly enclosing the fetus and the amniotic fluid. It continuous with the umbilical cord and covers the fetal surface of the placenta and is also the outer covering of the umbilical cord.

Amniotic Fluid

The amniotic fluid is the medium in which the fetus and the cord float inside the amniotic membrane. It is not a static state but is replaced every hour about 350-500 ml. Daily exchange of AF at 6 months is around 6 galloons.

Amniotic FluidHow it is produced?1. The fetus:

• Active secretion of the amniotic membrane

• Fetal urination .

2. Transudation from maternal circulation.

3. Removal or uptake of amniotic fluids is by;

• Absorption through the amnion to the maternal circulation

• By fetal swallowing

Amniotic FluidVolume:Volume:

a.a. The volume of the amniotic fluid The volume of the amniotic fluid increases from the first trimester increases from the first trimester until the 38until the 38thth week. week.

b.b. Normally AF volume ranges from Normally AF volume ranges from 500 to 1200 ml averaging from 500 to 1200 ml averaging from 1000ml.1000ml.

Composition:Composition:

a.a. Composed of 99% water and 1% Composed of 99% water and 1% solid particlessolid particles

b.b. Contains albumin, urea, minerals Contains albumin, urea, minerals and suspended materials and and suspended materials and vernix caseosavernix caseosa

Color:Color:a.a. It is clear and colorless to straw It is clear and colorless to straw

coloredcolored

b.b. Green tinged is abnormalGreen tinged is abnormal

c.c. Golden yellow is abnormalGolden yellow is abnormal

d.d. Gray is abnormalGray is abnormal

e.e. Bloody indicates Bloody indicates vasa previavasa previa

f.f. Brownish coffee or tea is abnormalBrownish coffee or tea is abnormal

Amniotic Fluid

PH: 7.0 to 7.25PH: 7.0 to 7.25

Specific Gravity: 1.005 to 1.025Specific Gravity: 1.005 to 1.025

Function of the AF:Function of the AF: ProtectionProtection Promotes symetric Promotes symetric

musculoskeletal developmentmusculoskeletal development Acts as a excretion and Acts as a excretion and

secretion systemsecretion system Source of oral fluid for the Source of oral fluid for the

fetus fetus DiagnosisDiagnosis Assist in labor.Assist in labor.

Amniotic Fluid

Amount of AF:Amount of AF: 30 ml at 10 weeks30 ml at 10 weeks 350 ml at 20 weeks350 ml at 20 weeks 800 to 1000 ml by 37 weeks800 to 1000 ml by 37 weeks

Oligohydramios reduction in the Oligohydramios reduction in the amount of AF (under 300ml)amount of AF (under 300ml)

Hydramnios excessive amniotic Hydramnios excessive amniotic fluid (more than 2000ml)fluid (more than 2000ml)

U m b i l i c a l C o r d

It main function is to carry oxygen and nutrients from the placenta to the fetus and return un-oxygenated blood and fetal waste product to the placenta. BLOOD VESSELS:

2 arteries, 1 vein

LENGHT: is about 50 to 55 cm long. It appears dull white moist and covered by the amnion.

Whartons Jelly is a gelatinous substance found inside the cord.

CORD INSERTION: Central Insertion Lateral Insertion Velamentous when the chorioamniotic membrane is inserted in the

membrane 5 to 10 cm away from the edge of the placenta Battledore cord id inserted at the edge of the placenta

PLACENTA

Placenta• The placenta rise out of the Tropoblast tissue• It serves as the fetal lung, kidneys and gastrointestinal tract and a

separate endocrine system throughout the pregnancy.• As early as 12th weeks of pregnancy maternal blood begins to

collect in spaces. • There is no directs exchange of blood between the embryo and

the mother during pregnancy “selection osmosis”• As the network of the chorionic villi increases with pregnancy it

will form a network and become separated by a series of partition or septa known as “cotyledons”

• Uterine perfusion is most efficient when the mother lies on her left side.

» Maternal side » Fetal side

• The nourishment of the placenta comes from the maternal blood and it can grow only up to a limited time (40-42).

Function of the PlacentaRespiratory System Renal SystemGatro-intestinal System Endocrine System the placenta produces the following hormones

HCG, Estrogen, Progesterone, and HPL, ACTH and Growth Hormones

• HCG rises sharply after implantation reaching a peak of 100,000 mIU/ml about the 60th day of pregnancy falls sharply to a level of 30,000 mIU/ml and is maintained at this level until term.

• HPL is growth promoting and lactogenic in nature. It is produced by the placenta beginning as early as 6 weeks or pregnancy an then increase in amount at term.

• Estrogene • Progesterone

Abnormalities of the Placenta

1. Placenta Bilobata: The placenta consists of two equal lobes connected by placental tissue.

2.Placenta Bipartita: The placenta consists of two equal parts connected by membranes. The umbilical cord is inserted in one lobe and branches from its vessels cross the membranes to the other lobe. Rarely, the umbilical cord divides into two branches, each supplies a lobe.

3. Placenta Succenturiata: The placenta consists of a large lobe and a smaller one connecting together by membranes. The umbilical cord is inserted into the large lobe and branches of its vessels cross the membranes to the small succenturiate (accessory) lobe. The accessory lobe may be retained in the uterus after delivery leading to postpartum haemorrhage. This is suspected if a circular gap is detected in the membranes from which blood vessels pass towards.

Abnormalities of the Placenta

Abnormal WeightThe placenta increases in size and weight as in congenital syphilis, hydropsfoetalis and diabetes mellitus.

Abnormal PositionPlacenta Praevia: The placenta is partly or completely attached to the lower uterine segment.

Abnormal AdhesionPlacenta Accreta: The chorionic villi penetrate deeply into the uterine wall to reach the myometrium, due to deficient deciduabasalis. When the villi penetrate deeply into the myometrium, it is called "placenta increta" and when they reach the peritoneal coat it is called "placenta percreta".

The Origin and Development of Organ System

• Cardiovascular System:– First system to become functional in intrauterine life. – The heart tube begins to forms early as 16th day and begin to beat as early as the

24th day.– As early as 3rd week of intrauterine life fetal blood begun to exchange nutrients with

the maternal circulation across the chorionic villi. The fetal circulation differs that of the extrauterine life.

– Blood arriving from the placenta contains high concentration of oxygen . (80%)– FHB is 120 to 160 bpm – Despite a low level of O2 level, CO2 does not accumulate in the fetal system because

of rapid diffusion into the maternal blood.

FETAL HEMOGLOBIN Composed of two alpha and two gamma Hemoglobin concentration 17.1 g/100ml of blood Hematocrit 53%

Ductus VenosusDuctus Venosus

Ductus ArteriosusDuctus Arteriosus

Foramen OvaleForamen Ovale

Ductus Arteriosus

Foramen Ovale

FETAL CIRCULATIONSTRUCTURE LOCATION FUNCTION

Placenta Attached to the Uterus

Gas exchange

Umbilical Arteries Two Arteries in the Cord

Carry UNO2 blood from the fetus to

the placenta

Umbilical Vein One Vein in the Cord

Carry O2 blood to the fetus

Foramen Ovale Opening in the inter-atrial septum

Shunts blood from the right atrium to the left atrium so

that blood can supplied the brain, heart and kidneys

Ductus Venosus Accessory vein connecting

umbilical vein into fetal liver and IVC

To supply blood to liver. A bypass to

the fetal liver

Ductus Arteriosus Connection between fetal

lungs and the aorta

Shunts larger portion if the blood

away from the lungs and directly

to the aorta

FETAL CIRCULATION

Blood from the Placenta

Umbilical Vein

Enter the Ductus Venosus

Passes through the IFC

Enter the Right Atrium

Left Ventricle Aorta

Right Atrium Enters the Right

Ventricle

Enters the Pulmonary Artery with some blood going to Lungs

Flows to the Ductus Arteriosus

Enters the Descending Aorta

Enters the Hypogastric

Artery goes back to Placenta

Nervous SystemNervous System 3rd week and 4th week a neural plate is apparent in

the developing embryo. Although the parts of the brain form into the uterus

the brain is not mature at birth. All during pregnancy and at birth the system is

vulnerable to damage

Endocrine SystemEndocrine System The fetal adrenal glands plays direct role in placental

estrogen production as they supply a precursor of estrogen synthesis

The fetal pancreas produces the insulin needed by the fetus

Digestive System 6th Week of IUL the abdomen become too small to contain

the intestine enters the base of the umbilical cord. 10th week time when the fetal trunk extended and enlarge.

OMPHALOCELE is a type of abdominal wall defect in which the intestines, liver, and occasionally other organs remain outside of the abdomen in a sac because of a defect in the development of the muscles of the abdominal wall.

Digestive System At 12th weeks the fetus swallows amniotic

fluid .Meconium form in the intestine as early as the 16th week. It consist of cellular waste, bile, fats , mucoproteins, mucopolysaccharides and portion of the verniz caseosa.

The gastro intestinal system is sterile before birth. The liver is active throughout gestation. Is still immature at birth. (hyperbilirubinemia and

hypoglycemia)

SKELETAL SYSTEM 4 weeks parts of the mesoderm gives rise to the

bones and muscle 13 week the skeleton begins to calcify

Respiratory System 7th week of IUL diaphragm completely divides

the thoracic cavity from the abdominal cavity.

Respiratory System 7th week of IUL diaphragm completely divides the

thoracic cavity from the abdominal cavity. Between the 24th and 28th weeks alveoli and capillaries

must be complete before gas exchange can occur in the fetal lungs

24th week of pregnancy alveolar cells begins to produce surfactants

Surfactants has two components Lecithin and Sphingomyelin (2:1)

INTEGUMENTARY SYSTEM The skin appears thin and translucent until

subcutaneous fats begins to deposited at about 36 weeks. (lanugo, vernix caseosa)

Immune System IgG gives the fetus temporary passive immunity

against disease for which the mother has antibodies (poliomyelitis, rubella, rubeola, diphtheria, tetanus, infectious parotitis, pertussis, ) little or no immunity against varicella or the herpes.

The level of passive immunity peaks at birth and then decrease over the next 9 months while the infant begins to develop their own stores of IgA and IgM.

Fetal Development

Fetal Development

Fetal Development

STAGES OF DEVELOPMENT

1 Month

• First TrimesterAt the end of four weeks:

• Baby is 1/4 inch in length • Heart, digestive system,

backbone and spinal cord begin to form

• Placenta (sometimes called "afterbirth") begins to develop

• The single fertilized egg is now 10,000 times larger than size at conception

Month 2

• First TrimesterAt the end of 8 weeks:

• Baby is 1-1/8 inches long • Heart is functioning • Eyes, nose, lips, tongue,

ears and teeth are forming • Penis begins to appear in

boys • Baby is moving, although

the mother can not yet feel movement

Month 3

• First TrimesterAt the end of 12 weeks:

• Baby is 2 1/2 to 3 inches long • Weight is about 1/2 to 1 ounce • Baby develops recognizable form.

Nails start to develop and earlobes are formed

• Arms, hands, fingers, legs, feet and toes are fully formed

• Eyes are almost fully developed • Baby has developed most of

his/her organs and tissues • Baby's heart rate can be heard at

10 weeks with a special instrument called a Doppler

4 months

Month 4

• Second TrimesterAt the end of 4 months:

• Baby is 6 1/2 to 7 inches long • Weight is about 6 to 7 ounces • Baby is developing reflexes, such

as sucking and swallowing and may begin sucking his/her thumb

• Tooth buds are developing • Sweat glands are forming on

palms and soles • Fingers and toes are well defined • Sex is identifiable • Skin is bright pink, transparent

and covered with soft, downy hair • Although recognizably human in

appearance, the baby would not be able to survive outside the mother's body

Month 5


• Baby is 8 to 10 inches long • Weight is about 1 pound • Hair begins to grow on baby's

head • Soft woolly hair called lanugo

will cover its body. Some may remain until a week after birth, when it is shed.

• Mother begins to feel fetal movement

• Internal organs are maturing • Eyebrows, eyelids and

eyelashes appear

Month 6


• Baby is 11 to 14 inches long

• Weight is about 1 3/4 to 2 pounds

• Eyelids begin to part and eyes open sometimes for short periods of time

• Skin is covered with protective coating called vernix

• Baby is able to hiccup

Month 7

• Third TrimesterAt the end of 7 months:

• Baby is 14 to 16 inches long • Weight is about 2 1/2 to 3 1/2

pounds • Taste buds have developed • Fat layers are forming • Organs are maturing • Skin is still wrinkled and red • If born at this time, baby will

be considered a premature baby and require special care

•

Month 8

• Third TrimesterAt the end of 8 months:

• Baby is 16 1/2 to 18 inches long • Weight is about 4 to 6 pounds • Overall growth is rapid this month • Tremendous brain growth occurs

at this time • Most body organs are now

developed with the exception of the lungs

• Movements or "kicks" are strong enough to be visible from the outside

• Kidneys are mature • Skin is less wrinkled • Fingernails now extend beyond

fingertips

Month 9

Third TrimesterAt the end of 9 months:

• Baby is 19 to 20 inches long

• Weight is about 7 to 7 1/2 pounds

• The lungs are mature • Baby is now fully

developed and can survive outside the mother's body

• Skin is pink and smooth • Baby settles down lower in

the abdomen in preparation for birth and may seem less active

VIABILITY

• Capability of fetus to survive outside uterus at the earliest gestational age - 22-24 weeks

• Survival depends on:– Maturity of fetal

central nervous system

– Maturity of lungs

4 Weeks

• At this point of development the structures that eventually form the face and neck are becoming evident. The heart and blood vessels continue to develop. And the lungs, stomach, and liver start to develop. A home pregnancy test is now positive.

8 Weeks

• The baby is now about the size of a grape - almost an inch in size. Eyelids and ears are forming and even the tip of the nose is visible. The arms and legs are well formed. The fingers and toes grow longer and more distinct.

12 Weeks

• The fetus measures about two and a half inches and starts to make its own movements. You may start to feel the top of your uterus above the pelvic bone. Your doctor may hear the baby's heartbeat with special instruments. The sex organs of the baby should start to become clear.

16 Weeks

• The fetus now measures about 4.3 to 4.6 inches and weighs about 2.8 ounces. The top of your uterus should be felt about three inches below your belly button. The baby's eyes can blink and the heart and blood vessels are fully formed. The baby's fingers and toes should have fingerprints.

20 Weeks

• The baby weighs about 9 ounces and is about six inches long. The uterus should be at the level of the belly button. The baby can suck a thumb, yawn, stretch, and make faces. Soon -- if you haven't already -- you'll feel your baby move, which is called "quickening."

• An ultrasound is generally performed for all pregnant women at 20 weeks of gestation. During this ultrasound, the doctor will confirm that the placenta is healthy and attached normally and that your baby is growing properly in the uterus. The baby's heartbeat and movement of its body, arms, and legs can also be seen on the ultrasound. The gender of the baby can usually be determined at 20 weeks.

24 Weeks• The fetus weighs about

1.4 pounds now. It responds to sounds by moving or increasing its pulse. You may notice jerking motions if it hiccups. With the inner ear fully developed, it may be able to sense being upside down in the womb.

28 Weeks• The fetus weighs about 2

pounds 6 ounces. It changes position frequently at this point in pregnancy. There's a good chance of survival if your baby was born prematurely now. Ask your doctor about preterm labor warning signs. Register for birthing classes. Birthing classes prepare you for many aspects of childbirth, including labor and delivery and parenting the newborn.

32 Weeks• Often on the move, the

fetus weighs almost 4 pounds. The baby's skin has less wrinkles as a layer of fat starts to form under the skin. It will gain up to half its birth weight between now and delivery. Ask your doctor how to do a fetal movement chart. Think about breastfeeding. Soon you may start leaking colostrum from your breasts, a yellowish fluid that precedes milk production.

36 Weeks

• Fetal development at 36 weeks• Babies differ in size, depending on

many factors (such as gender, the number of babies being carried, and size of the parents), so your baby's overall rate of growth is as important as the actual size. On average, it's about 12.5 inches and weighs 5.5 pounds. The brain has been developing rapidly. Lungs are nearly fully developed. The head is usually positioned down into the pelvis by now. A pregnancy is considered 'at term' once 37 weeks has been completed; baby is ready!

40 WeeksA mother's due date marks the end of her 40th week. A pregnancy begins with implantation and the delivery date can be calculated using the first day of the last period. Based on this, pregnancy can last between 38 and 42 weeks with a 'full term' delivery occurring around 40 weeks. Some post-term pregnancies - those lasting more than 42 weeks - are not truly post-term. A common "cause" is an incorrect due date. For safety reasons, most babies are delivered by 42 weeks, inducing labor if necessary.

Pregnancy Presumptive Signs

M ORNING SICKNESS

A MENORRHEA

C HANGES IN BREAST

F ATIGUE

L ASSITUDE

U RINARY F REQUENCY

Q UICKENING (18TH 20TH WEEK)

S KIN CHANGES

Probable Signs

C hadwicvks H egar U terine Enlargement P ositive Pregnancy Test B alottment O utlining of fetal body G oodells S ouffle contraction and

BHC (28th)

Pregnancy Positive Sign

Fetal Heartbeat (10 weeks Doppler)

(16 weeks fetoscope)(18 to 20 weeks Stet.)

Fetal Movement felt usually after 20 weeks

Fetal Skeleton

The F.U.N of E. D. C.

• Fundal Height– Above symphysis pubis (12 to 14 weeks AOG)– If at the level of umbilicus (20 weeks)– THEN 1 CM until 36 weeks AOG

The F.U.N of E. D. C.

• Naegele’s Rule– Count back three months from the 1st day of last

menses and add seven days and one year (except January, February and March)

• For example the last menstrual period (LMP) began

July 30, 2010.

EDC ?????

Assessment of the Fetal Well Being

Amniocentesis Aspiration of the fluid from the uterus Done at 14 to 16 weeks of pregnancy The needle used is a 3 or 4 inches, 20 to 22 gauge spinal needle

Do not ask the mother to take a deep breath A syringe is inserted and about 10 to 20 ml of fluid is removed.

Provides the following information: Color LS ratio Bilirubin determination Chromosome analysis AFP

Assessment of the Fetal Well Being

Fetoscopy Visualization of the fetus by inspection through

fetoscope To confirm the intactness of the spinal column To obtain biopsy samples of the fetus To perform elemental surgery Can be performed as early as the 16th or 17th week

visuali

Conception/Obstetrics Nursing

Health & Medicine

chorionic villi

maternal circulation

umbilical cord

fallopian tube

genetic defects

vessels cross

endocrine system

blood vessels