Physiological changes in second stage of laborDR MUKESH SAH
There is an interplay of physiological processes occurring during the second stage of labour. Second stage is said to have two phases, latent and active. It is during the latent phase that the presenting part passes through the fully dilated cervix to the birth canal.
Abnormalities of placenta and cord obgjagan _jaggi
Has a velamentous insertion of the cord (the umbilical cord inserts abnormally into the fetal membranes, instead of the center of the placenta) Has placenta previa (a low-lying placenta that covers part or all of the cervix) or certain other placental abnormalities.
Physiological changes in second stage of laborDR MUKESH SAH
There is an interplay of physiological processes occurring during the second stage of labour. Second stage is said to have two phases, latent and active. It is during the latent phase that the presenting part passes through the fully dilated cervix to the birth canal.
Abnormalities of placenta and cord obgjagan _jaggi
Has a velamentous insertion of the cord (the umbilical cord inserts abnormally into the fetal membranes, instead of the center of the placenta) Has placenta previa (a low-lying placenta that covers part or all of the cervix) or certain other placental abnormalities.
Majority of fetal deaths occur in the antepartum period.
There is progressive decline in maternal deaths all over the world. Currently more interest is focused to evaluate the fetal health. The primary objective of antenatal assessment is to avoid fetal death.
Majority of fetal deaths occur in the antepartum period.
There is progressive decline in maternal deaths all over the world. Currently more interest is focused to evaluate the fetal health. The primary objective of antenatal assessment is to avoid fetal death.
Maternal Care: Medical problems during pregnancy, labour and the puerperiumSaide OER Africa
Maternal Care addresses all the common and important problems that occur during pregnancy, labour, delivery and the puerperium. It covers: the antenatal and postnatal care of healthy women with normal pregnancies, monitoring and managing the progress of labour, specific medical problems during pregnancy, labour and the puerperium, family planning, regionalised perinatal care
Amniotic fluid maintain the perfect homeostasis between mother and fetus. It protect both mother and fetus from various complications. Details is enclosed in presentation.
The placenta is a large organ that develops during pregnancy.Blood from the mother passes through the placenta, filtering oxygen, glucose and other nutrients to your baby via the umbilical cord.
USMLE GENERAL EMBRYOLOGY 008 First week of development A embryo .pdfAHMED ASHOUR
The initial week of embryonic development is a vital period commencing with fertilization, leading to the creation of the zygote and early cell divisions. It's noteworthy that, throughout this week, the developing embryo remains in the pre-implantation stage, journeying from the fallopian tube toward the uterus. Key events such as fertilization, cleavage, and the formation of the blastocyst are crucial for the embryo's early development.
These events lay the foundation for subsequent processes in the following weeks. The successful implantation of the blastocyst into the uterus marks the transition from the first week to the second week of embryonic development.
Gametogenesis and Pre-ebryonic life by Shapi. MDpdfShapi. MD
A well summarized presentation on the Basics in the science of the Human Anatomy that'll effectively deliver information in an incredibly remarkable way to the reader.
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
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New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
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Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
4. GAMETOGENESIS Cont...
10/21/2016
• Both mitosis and meiosis play a role in
gametogenesis.
• Mitosis provides the precursor cells.
• Meiosis brings about the reduction
divisions that result in gametes.
4
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7. 10/21/2016 7Prepared by: Heera KC: Conception and fetal development
OOGENESIS
Oogenesis
The process involved in the development of a mature ovum is called
oogenesis.
8. Fully matured ovum
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Fully mature ovum :
largest cell in the body,
130 micron in diameter.
Cytoplasm
23 chromosomes(23 x)
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Spermatogenesis
The process involved in the development of spermatids
from the primordial male germ cells and their
differentiation into spermatozoa is called spermatogenesis.
Primary spermatocytes
16 days.
61 days
10. Structure of a mature spermatozoon
• It has got two parts, a head
and a tail.
• The head
Condensed nucleus and
acrosomal cap.
Acrosome is rich in
enzymes.
• The tail divided into four
zones — the neck, the
middle piece, the principal
piece and the end piece.
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10
11. Difference between spermatogenesis and
oogenesis.
Spermatogenesis differs from oogenesis in three
ways
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11
1. All four products of meiosis develop into sperm while
only one of the four becomes an egg.
2. Spermatogenesis occurs throughout adolescence and
adulthood.
3. Sperm are produced continuously without the prolonged
interruptions like in oogenesis.
13. Ovulation
10/21/2016
Ovulation is
a process
whereby a
secondary
oocyte is
released
from the
ovary
following
rupure
13
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of a mature Graafian follicle and becomes available
for conception.
Day 12
Day 1
Day 14Day 20
Day 28
14. In each ovarian cycle, Only one secondary oocyte is
likely to rupture.
It starts at puberty and ends in menopause.
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Ovulation cont...
15. 10/21/2016 15
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Ovulation cont...
Mechanism
Changes in follicle
Changes in oocyte
Preovulatory
changes
16. • Preovulatory enlargement of the Graafian follicle
due to accumulation of follicular fluid.
• Measures about 20 mm in diameter.
• The cumulus oophorus separates from the rest of the
granulosa cells.
• The follicular wall near the ovarian surface becomes
thinner.
Changes in the follicle
10/21/2016 16 Prepared by: Heera KC: Conception and fetal development
17. • ovarian cycle
10/21/2016 Prepared by: Heera KC: Conception and fetal development 17
Schematic diagram showing: (A) Mature Graafian follicle on the verge of ovulation (B)
Ovulation with discharge of secondary oocyte surrounded by cumulus oophorus (C) Formation of
corpus luteum (D) Secondary oocyte after first maturation division with formation of first polar
body and (E) Microscopic structure of corpus luteum
18. Significant changes occur just prior to ovulation
(few hours).
Cytoplasmic volume is increased.
Completion of the arrested first meiotic division
occurs with extrusion of first polar body, each
containing haploid number of chromosomes (23, X).
Changes in the oocyte
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19. CAUSES
10/21/2016 20
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2.Stretching factor(a passive stretching process
of granulosa cells.)
Contraction of the micromuscles in the theca
externa and ovarian stroma due to increased
prostaglandin secretion.
Endocrinal
•LH surge
•FSH rise
20. Endocrinal
10/21/2016 21
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LH surge: Sustained peak level of estrogen for 24–36
hours in the late follicular phase →
LH surge occurs from the anterior pituitary.
•Ovulation approximately occurs 16–24 hours after the
LH surge.
•LH peak persists for about 24 hours.
21. Endocrinal
10/21/2016 22
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The LH surge stimulates completion of reduction
division of the oocyte and initiates luteinization of the
granulosa cells, synthesis of progesterone and
prostaglandins
FSH rise: Preovulatory rise of progesterone
facilitates the positive feedback action of estrogen to
induce FSH surge → increase in plasminogen
activator → plasminogen → plasmin → helps lysis
of the wall of the follicle.
22. The follicle is changed
into corpus luteum.
EFFECT OF OVULATION
10/21/2016 23
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Menstruation is unrelated with ovulation.
The ovum is picked up into the Fallopian tube, and
undergoes either degeneration or further
maturation,if fertilization is to occur.
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24
Reproductive
cycle
A. Ovarian cycle-
B. Anterior
pituitary cycle
C. Ovarian
hormones
D. Uterine cycle
Proliferative phasephase
Secretory phase
24. • Fertilization is the process of fusion of the
spermatozoon with the mature ovum.
• It begins with sperm egg collision and ends with
production of a mononucleated single cell called the
zygote.
Definition
10/21/2016 25 Prepared by: Heera KC: Conception and fetal development
25. FERTILIZATION Cont...
10/21/2016
(1) To initiate the embryonic development of the
egg and
(2) To restore the chromosome number of the
species.
26Prepared by: Heera KC: Conception and fetal development
Objectives
26. FERTILIZATION Cont...
10/21/2016
Almost always, fertilization occurs in the
ampullary part of the uterine tube.
27Prepared by: Heera KC: Conception and fetal development
Normal site for conception/ Fertilization
27. APPROXIMATION OF THE GAMETES
• Fertilizable life span of oocyte is 12 to 24
hours and sperm is 48 to 72 hours.
• Out of hundreds of millions of sperms
deposited in the vagina at single ejaculation,
only thousands capacitated spermatozoa enter
the uterine tube while only 300–500 reach the
ovum.
10/21/2016 Prepared by: Heera KC: Conception and fetal development 28
28. APPROXIMATION OF THE GAMETES
Tubal transport is
facilitated by muscular
contraction and
aspiration action of the
uterine tube.
10/21/2016 Prepared by: Heera KC: Conception and fetal development 29
It takes only few minutes for the sperm to reach
the Fallopian tube
29. CONTACT AND FUSION OF THE GAMETES
• Capacitation
• Acrosomal Reaction
• Cortical Reaction
• Development of zygote
10/21/2016
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30
30. Capacitation
• The process of undertaking in the sperm when
inside the female genital tract influenced by the
secretions of the uterine tube is known as
capacitation.
• Sperm must be in the female genital tract 4-6
hours before they can fertilize an ovum.
• The sperm undergoes changes in the removal of
the glycoprotein coat.
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31
31. Acrosomal Reaction
• The acrosomal
layer of the sperm
becomes reactive
and releases the
enzyme
hyaluronidase
known as the
acrosome
reaction .
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32
It disperses the corona radiata
(outer layer of ovum) allowing
access to the zona pellucida .
32. Cortical Reaction
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33
• Penetration of the zona pellucida occurs with
the aid of several enzymes processed by the
sperm which breaks down the proteins of the
zona layer.
• Upon penetration a chemical reaction known
as the cortical reaction occurs which makes it
impermeable to other sperms.
The first sperm that reaches the zona
pellucida penetrates it.
33. • The plasma membrane of the sperm and oocyte
fuse.
• The oocyte at this stage completes the second
meiotic division and becomes mature, the
pronuclei has 23 haploid chromosomes.
• Male and female pronuclei fuses to form a new
nucleus that is a combination of the genetic
material from both the sperm and the oocyte
diploid cell.
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34
Cortical Reaction
34. DEVELOPMENT OF ZYGOTE
• The male and
female gametes
each contribute
half the
complement of
chromosomes to
make a total of
46. The new cell
is called zygote.
10/21/2016 Prepared by: Heera KC: Conception and fetal development 35
35. CONTACT AND FUSION OF THE GAMETES
10/21/2016
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36
Schematic diagram showing sequence of changes during fertilization :
(A) Sperm (acrosome intact) in between the corona radiata cells → attachment with zona →
acrosome reacted sperm penetrating the zona → acrosome reacted sperm in the perivitelline
space → incorporated sperm with vesiculating head. (B) Formation of male and female
pronuclei with completion of second polar body
A B
36. Zygote cont...
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37
The zygote, thus formed, contains both
the paternal and maternal genetic
materials.
Sex of the child is determined by the pattern of the
sex chromosome supplied by the spermatozoon.
If the spermatozoon contains ‘X’ chromosome, a
female embryo (46, XX) is formed; if it contains a ‘Y’
chromosome, a male embryo (46, XY) is formed.
37. DEVELOPMENT OF ZYGOTE
Divided into three periods:
–Pre-embryonic period: 1st two weeks after
fertilization.
–Embryonic period: 2- 8 weeks
–Fetal period: 8 weeks to birth.
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38
38. PRE-EMBRYONIC PERIOD
• This period includes the implantation of the
zygote into the endometrium.
• The embryo takes about 3 days to travel
through the fallopian tube to reach the uterus.
10/21/2016 Prepared by: Heera KC: Conception and fetal development 39
39. PRE-EMBRYONIC PERIOD
• It takes another 3 days to get implanted,
usually in the dorsal wall of the uterus .
• Thus embryo is about 1 week old when it gets
implanted.
10/21/2016 Prepared by: Heera KC: Conception and fetal development 40
40. PRE-EMBRYONIC cont...
• Zygote undergoes mitotic division and cellular
replication known as cleavage which results in the
formation of smaller cells known as blastomers.
• During this period a strong membrane of
glycoprotein called zona pellucida surrounds the
zygote.
• The zygote mainly gets nourishment (glycogen)
from the goblet cells of the uterine tubes and later
the secretory cells of the uterus.
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41
41. PRE-EMBRYONIC PERIOD cont...
The zygote divides
into
• 2 cells at day 1, (or
30 hours)
• 4 at 2 days,
• 8 by 2.5 days,
• 16 by 3 days, now
known as
morula,
Resembling a
mulberry. (16-64
cell stage)
10/21/2016 Prepared by: Heera KC: Conception and fetal development 42
42. • Cells bind tightly together in a process known
as compactation.
• Next cavitation occurs whereby the outermost
cells secrete fluid into the morula and a fluid
filled cavity or blastocele appears.
• This results in the formation of the blastula or
blastocyst comprising 58 cells.
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43
PRE-EMBRYONIC PERIOD cont...
43. 10/21/2016
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44
Schematic representation of the mitotic division of the
zygote resulting in formation of: (A) Two-cell stage; (B)
Four-cell stage; (C) Morula and (D) Blastocyst
A B C D
44. • Development of the morula to
the blastocyst, has occurred by
day 4.
•
Blastulation
10/21/2016 Prepared by: Heera KC: Conception and fetal development 45
Blastocyst
Trophoblast
Placenta
chorion
Inner cell
mass
Fetus
Amnion
Umbilical
cord
45. 10/21/2016
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46
Diagrammatic representation of the events — ovulation, fertilization and
implantation: (1) Secondary oocyte extruded at ovulation (2) Secondary
oocyte in tube (3) Fertilization with extrusion of second polar body (day
14–16) (4) Formation of zygote (5) Two-cell stage (6) Four-cell stage (7)
Early morula (day 17) (8) Late morula (day 18) (9) Early blastocyst stage
with disappearance of zona pellucida (day 19–20) (10) Early phase of
implantation (day 20–21)
46. IMPLANTATION
Schematic representation showing interstitial implantation of the blastocyst in stratum
compactum of the decidua
10/21/2016 47
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fetal development
47. • Embedding of the embryo to the walls of
uterus.
• Also called as Nidation.
• Occurs in the endometrium of the anterior or
posterior wall of the body near the fundus on
the 6th day which corresponds to the 20th
day of a regular menstrual cycle.
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IMPLANTATION cont...
48. • Implantation occurs through four stages.
apposition, adhesion, penetration and invasion.
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IMPLANTATION cont...
APPOSITION: Occurs through pinopod formation.
Pinopods are long finger like projections (microvilli)
from the endometrial cell surface.
These pinopods absorb the endometrial fluid which is
secreted by the endometrial gland cells. This fluid, rich in
glycogen and mucin provides nutrition to the blastocyst
initially.
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IMPLANTATION cont...
Unless this fluid is absorbed, adhesion phase cannot occur.
Adhesion of blastocyst to the endometrium occurs through
the adhesion molecules like integrin, selectin and cadherin
(glycoproteins).
Penetration and invasion occur through the stromal cells in
between the glands and is facilitated by the histolytic action of
the blastocyst.
With increasing lysis of the stromal cells, the blastocyst is
burrowed more and more inside the stratum compactum of
the decidua.
51. THE DECIDUA
1. The basal layer: Lies immediately above the
myometrium. Remains unchanged in itself but
regenerates the new endometrium during the
puerperium.
2. The functional layer: consists of tortuous glands
which are rich in secretions.
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It provides a secure anchorage for the placenta
and allows it access to nutrition and oxygen, but
as soon as the baby is born separation can occur.
52. 3.The compact layer: This layer forms the
surface of the decidua and is composed of
closely packed stroma cells and the neck of the
glands.
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THE DECIDUA
BASAL DECIDUA: underneath the blastocyst.
CAPSULAR DECIDUA: that which covers it.
PARIETAL DECIDUA: remainder of the decidua (true
decidua)
53. Functions
(1) It provides a good nidus for the implantation of the
blastocyst.
(2) It supplies nutrition to the early stage of the growing
ovum by its rich sources of glycogen and fat.
(3) Deeper penetration of the trophoblast is controlled
by local peptides, cytokines and integrins.
(4) Decidua basalis takes part in the formation of
basal plate of the placenta.
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54. GASTRULATION
Embryo Development
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1.Outer Syncytiotrophoblast (syncytium):
•Layer composed of nuclear protoplasm, capable of breaking
down the tissues in the process of embedding.
Function: Makes nutrients in maternal blood accessible to
the developing embryo.
During week 2nd, the
trophoblast proliferates and
differentiates into layers.
55. Gastrulation cont...
2. Inner Cytotrophoblast:
A well defined single layer of cells which produce
a hormone HCG.
This hormone is responsible to inform the corpus
luteum that pregnancy has begun.
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3. A layer of Mesoderm or the primitive gut:
Layer having cells similar to inner cell mass.
Simultaneously to implantation, the embryo is
developing from the embryoblast.
56. Embryoblast differentiate into two
layers
a. Epiblast : closest to the trophoblast, gives rise
to cells of the embryo. Epiblast again gives rise
to three layers which are collectively known as
the primitive streak at around day 15.
b. Hypoblast: closest to the blastocyst cavity.
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Bilaminar disc differentiating into
trilaminar disc.(week 3)
61. GASTRULA LAYERS DEVELOP
1. The Ectoderm: skin and the nervous system.
2. The Mesoderm: bones, muscles, heart, blood
vessels and some visceral organs.
3. The Endoderm: mucous membranes and
glands
Two cavities appear on either side of the
embryonic plate.
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INTO…PRIMARY GERM LAYERS
63. The amniotic
cavity
Epiblast separates
from the trophoblast
and forms a cavity that
lies on the side of the
ectoderm, derives from
the ectoderm layer.
Filled with fluid,
enlarges and folds
around the embryo
gradually.
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2. The yolk
sac
Cavity that lies on the
side of the endoderm
and develops from the
hypoblast.
Provides nourishment
for the embryo untill
the trophoblast is
sufficiently developed
to take over.
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Schematic
representation of
formation of amniotic
cavity, secondary yolk
sac, extraembryonic
coelom and body stalk:
(A) Enlargement of
extraembryonic
coelomic cavity (B)
The amniotic sac
enlarges and begins to
occupy the
extraembryonic coelom
(C) The amniotic sac
has surrounded the
embryo with almost
completely obliterating
theextraembryonic
coelom; formation of
body stalk completed
65. DEVELOPMENT OF PLACENTA
• By the end of 2nd month, trophoblast is
charactered by great no. of secondary & tertiary
villi.
• By four month cytotrophblastic cells &
connective tissue disappears, only syncytium &
endothelial vessel remains (tertiary villi).
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66. DEVELOPMENT OF PLACENTA
• In early stage, villi covers the entire surface of
chorion.
• As, the pergnancy advances, villi on embryonic
pole continues to grow & expand – chorion
frondosum (bushy chorion).
• Villi on an embryonic pole degenerate- chorion
levae. The fusion of amnion & chorion occurs
to form aminochorionic membrane.
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68. Placenta is an organ that connects the
developing fetus to the uterine wall to allow
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•Nutrient uptake
•Waste elimination
•Gas exchange via
the mother’s blood
supply
•Hormone
production
•Formation of a
barrier.
Function as a
fetomaternal organ
with 2 components-
Fetal placenta
Maternal placenta
69. THE “PLACENTAL BARRIER”
• Sugars, fats and oxygen diffuse from mother’s
blood to fetus
• Urea and CO2 diffuse from fetus to mother
• Maternal antibodies actively transported across
placenta
– Some resistance to disease (passive immunity)
• Most bacteria are blocked
• Many viruses can pass including rubella,
chickenpox, sometimes HIV
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70. THE “PLACENTAL BARRIER”
• Many drugs and toxins pass including
alcohol, heroin, mercury
• Placental secretion of hormones
–Progesterone and HCG (human
chorionic gonadotropin, the hormone
tested for pregnancy): maintain the uterus
–Estrogens and CRH (corticotropin
releasing hormone): promote labor
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73. 1 Month
• First Trimester
At the end of four weeks:
• Baby is 1/4 inch in length.
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Placenta (sometimes called "afterbirth") begins to
develop.
The single fertilized egg is now 10,000 times larger
than size at conception
Heart, digestive system, backbone and spinal cord
begin to form.
74. Month 2
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FirstTrimester
At 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.
•The limb buds are now clearly arms and legs, while
the fingers and toes are still developing.
75. Month 3
(FirstTrimester)
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At the end of 12 weeks:
Baby is 2 1/2 to 3 inches
long (4.4cm)
Weight is about 1/2 to 1
ounce.
Baby develops recognizable form. Nails start to develop and
earlobes, arms, hands, fingers, legs, feet and toes are fully
formed.
Eyes are almost fully developed .
Baby's heart rate can be heard at 10 weeks with a special
instrument called a Doppler.
Baby has developed most of his/her organs and tissues .
76. Month 4
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At the end of 4 months:
• Baby is 6 1/2 to 7 inches long
• Weight is about 6 to 7 ounces
Developing reflexes, such as sucking and swallowing. may
begin sucking his/her thumb .Tooth buds are developing. Eyes
blink.
Sweat glands are forming on palms and soles, well defined
Fingers and toes . Sex is identifiable .
Bright pink, transparent skin covered with soft, downy hair .
Although recognizably human in appearance, the baby would
not be able to survive outside the mother's body.
Second Trimester
77. • Baby is 8 to 10 inches long
(13.2 cm)
• Weight is about 1 pound.
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At the end of 5 months
•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.
78. At the end of 6 months
• 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.
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Month 6
•The baby's inner ear
canals are developed at 24
weeks, so researchers
speculate the baby can
sense its position in the
uterus.
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Month 7 • Third Trimester
At the end of 7
months:
• 14 to 16 inches
long.
• 2 1/2 to 3 1/2
pounds
• Taste buds
developed .
• Fat layers are
forming.
• Organs are
maturing .
•Skin still wrinkled and red.
• If born at this time, baby will
be considered a premature
baby and require special care.
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Month 8 (Third Trimester) At the end of 8 months:
• 16 1/2 to 18 inches long
• 4 to 6 pounds weight.
• 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.
81. Third Trimester
At 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
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Month
9
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
82. FETAL MEMBRANES
• Amnion
Smooth, tough, translucent membrane derived from
inner cell mass.
Have role in the formation of amniotic fluid .
• Chorion
Thick, opaque, friable membrane, derived from
trophoblast.
Continuous with the chorionic plate which forms the
base of the placenta.
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83. REFERENCES
• Dutta D.C. Text book of gynaecology,calcutta 8th edition : New Central
Agency. 2005. P. 74-89
• Bennett Ruth V., Brown Linda K. Myles text book of midwives. 13th edition.
Harcourt Publishers; Churchill Livingstone. 1999. P. 963-979
• Bijlani RL. Understanding medical physiology: a text book for medical
students. Third edition. New Delhi; Emca house, Jaypee Brothers Medical
Publishers Pvt. Ltd. P . 577-583
• Leifer G. Introduction to maternity and pediatric nursing. Sixth edition.USA:
Elsevier Inc; Elsevier Saunders. 2011. P. 31-41
• Pillitteri Adele. Maternal and child health nursing. Fourth edition. Quebecor
Versailles prints: Lippincott William Wilkins. 2003. P.67 – 84
• Internet citation on title embryology (cited date:27/september 2016)
http://www.medicinenet.com/fetal_development_pictures_slideshow/article.htm l
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The process involved in the maturation of two highly specialized cells , spermatozoon in male and ovum in female before they unite to form zygote is called GAMETOGENESIS
Two new genetically identical daughter cells.(46 chromosomes)
By half and 4 gamate cells.
Replication : capable of division/copying/duplicating genetic material and dividing into two.
Four daughter cells. All differ from parents cells and with each other.
Genetic diversity and uniqueness with each other.
Maturation: reduction in half.
Cytoplasm.
anovular menstruation is quite
common during adolescence, following childbirth and in women approaching menopause.
maturation of follicles and development of corpus luteum.
LH and FSH levels.
estrogen and progesterone
Menstrual, proliferative and secretory
Series of events ocuring regularly in female.
ovum, immediately following ovulation is picked up by the tubal fimbriae which partly envelope the ovary, especially at the time of ovulation
ovum, immediately following ovulation is picked up by the tubal fimbriae which partly envelope the ovary, especially at the time of ovulation
Mitotic division. Binary division.
Basal decidua/serotina.- contact with base of decidua.
Gastrulation is a phase early in the embryonic development of most animals, during which the single-layered blastula is reorganized into a trilaminar ("three-layered") structure known as the gastrula. These three germ layers are known as the ectoderm, mesoderm, and endoderm.
The yolk sac becomes partly incorporated into the embryo to form the
gut. The part that remains outside is incorporated into the body stalk
A home pregnancy test should be positive at this stage of development (most tests claim positive results one week after a missed period).