A practical guide to first trimester of pregnancy

A Practical Guide to

First Trimester of Pregnancy



A Practical Guide to

First Trimester of Pregnancy

Editors

Mala Arora FRCOG (UK) FICOG FICMCH
Director, Noble IVF Centre, Faridabad, Haryana, India
Consultant, Fortis La Femme, Greater Kailash, New Delhi, India

Alok Sharma MD DHA MICOG
Consultant, Obstetrics and Gynecology
Deen Dayal Upadhyaya Hospital
Shimla, Himachal Pradesh, India

Foreword

Hema Divakar

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First Edition: 2014
ISBN 978-93-5152-178-5
Printed at


Dedications

This book is dedicated to my eternal guru Sri Paramhansa Yogananda, founder of Self
Realization fellowship (USA) and Yogoda Satsanga Society (India). His invisible guidance
was vital for the completion of this manuscript.
My parents who have laid the foundation stone of literacy in me.
My husband Dr Narinder Pal who has not only allowed me to concentrate on my writing
but has guided me at every step.
My children who have made me proud by out shining me in every aspect.

Mala Arora

My parents, Smt Dhanwanti Sharma and Shri Hansraj Sharma
for shaping my character in my formative years.
My wife, Dr Pratibha Sharma for her immense patience and guidance.
My lovely daughter, Hiranya Sharma.

Alok Sharma



Contents

Contributors
Foreword

Preface
Acknowledgments
1. Physiological Changes


68

Sunita Tandulwadkar, Bhavana Mittal, Pooja Lodha

11. Prescription Writing


60

Sangeeta Tejpuria

10. Supportive Drug Use


52

Prashant Acharya, Ashini Acharya

9.Vaccination


44

Anita Kaul

8. Invasive Procedures


38

S Shantha Kumari, D Vidyadhari

7. First Trimester Screening


32

Anupam Gupta

6. Hyperemesis Gravidarum


21

Kanthi Bansal

5. Nausea and Vomiting


14

Bhaskar Pal, Seetha Ramamurthy (Pal)

4. Diet Counseling

6

Jayprakash Shah, Parth Shah

3. The Booking Visit


1

Suvarna S Khadilkar, Deepali Patil

2. Dating and Chorionicity


xi
xv
xvii
xix

Ashis K Mukhopadhyay, Sagnika Dash

74


viii A Practical Guide to First Trimester of Pregnancy
12. Effect of Tobacco, Substance Misuse and Alcohol Abuse


13. Travel Guidelines

190

Suchitra N Pandit, Deepali P Kale

28. Laparoscopic Surgery


183

Krishna Kavita Ramavath

27. Surgery and Anesthesia


178

Bharati Dhorepatil, Arati Rapol

26. Twin Pregnancy


171

Mala Arora, Ritu Joshi

25. In Vitro Fertilization Conception

164

Rajat Ray, Yogita Dogra

24. Recurrent First Trimester Pregnancy Loss


156

Madhuri Patel, Rahul Chauhan

23. Associated Gynecological Conditions


152

Roza Olyai

22. Breast Diseases


144

Sujata Misra, Sudhanshu Nanda

21. Vaginal Discharge


138

Subhash C Biswas, Ram P Dey

20. Medical Disorders


131

Sarita Agarwal

19. TORCH Infection


123

Harshad Parasnis

18. HIV Positive Mother


113

Ameet Patki, Alok Sharma

17. Gestational Trophoblastic Disease


106

Nalini Mahajan, Shivani Singh

16. Ectopic Pregnancy


98

Maninder Ahuja

15. Pain Abdomen


93

Pratap Kumar, Alok Sharma

14. Role of Exercise and Bed Rest


86

Shashi Prateek, Ananya Banerjee, Deepali Dhingra

Punita Bhardawaj

206


Contents
29. Sexual Behavior

30. Vaginal Bleeding


239

Neela Mukhopadhaya, Kusum G Kapoor, Pragya M Choudhary

32. Termination of Pregnancy


230

Sadhana Gupta

31. Sepsis


225

Asmita M Rathore, Reena Rani

246

Kiran Kurtkoti

33. Medico Legal Aspects Termination of Pregnancy


MC Patel

Annexures: Practical Tips for Ultrasound



Ajay V Valia

Index

252

257

305

ix



Contributors
Editors
Mala Arora FRCOG (UK) FICOG FICMCH
Director, Noble IVF Centre, Faridabad
Haryana, India
Consultant, Fortis La Femme, Greater Kailash
New Delhi, India

Alok Sharma MD DHA MICOG
Consultant, Obstetrics and Gynecology

Deen Dayal Upadhyaya Hospital
Shimla, Himachal Pradesh, India

Contributing Authors
Prashant Acharya MD FICOG
Consultant, Fetal Medicine and High Risk Obstetric
care
Paras Advanced Centre for Fetal Medicine
Ahmedabad, Gujarat, India
Ashini Acharya MD
Consultant, Fetal Medicine and High Risk
Obstetric Care
Paras Advanced Centre for Fetal Medicine
Ahmedabad, Gujarat, India

Ananya Banerjee MD
Senior Resident, Department of Obstetrics and
Gynecology
Vardhman Mahavir Medical College and
Safdarjung Hospital
New Delhi, India
Kanthi Bansal MD DGO FICOG
Director, Safal Fertility Foundation
Ahmedabad, Gujarat, India

Sarita Agarwal MD FICOG FIAMS FCGP
Professor and Head, Department of Obstetrics and
Gynecology
All India Institute of Medical Sciences
Raipur, Chhattisgarh, India

Punita Bhardawaj MD
Senior Consultant, Division of Minimally Invasive
Gynecology
Institute of Minimal Access, Metabolic Surgery
Max Hospital, Saket
New Delhi, India

Maninder Ahuja DGO FICOG
Director, Ahuja Hospital and Infertility Centre
Visiting Consultant, Asian Institute of Medical
Sciences
Faridabad, Haryana, India

Subhash C Biswas MD FICOG FIMSA
Professor and Head, Department of Obstetrics and
Gynecology
Burdwan Medical College
Kolkata, West Bengal, India


xii A Practical Guide to First Trimester of Pregnancy
Rahul Chauhan MD
Senior Resident, N Wadia Maternity Hospital
Mumbai, Maharashtra, India
Sagnika Dash MBBS
Junior Resident
CSS College of Obstetrics, Gynecology and
Childhealth
Kolkata, West Bengal, India

Deepali Dhingra MD
Senior Resident, Department of Obstetrics and
Gynecology
Vardhman Mahavir Medical College and
Safdarjung Hospital
New Delhi, India
Bharati Dhorepatil DNB DGO Diploma Endoscopy

Ritu Joshi MS
Honorary Consultant, Obstetrics and Gynecology
Monilek Hospital and Research Centre
Consultant, Fortis Escorts Hospital
Jaipur, Rajasthan, India
Ashis K Mukhopadhyay MD
Professor and Unit-in-Charge, Obstetrics and
Gynecology
Medical Superintendent-cum-Vice Principal
CSS College of Obstetrics, Gynecology and
Childhealth, Kolkata, West Bengal, India
Anita Kaul MD
Senior Consultant, Apollo Centre for Fetal
Medicine
Indraprastha Apollo Hospitals
New Delhi, India

(Germany) FICS PGDCR

Director and Chief IVF Consultant
Pune Fertility Centre
Pune, Maharashtra, India

Yogita Dogra MD
Registrar, Kamla Nehru State Hospital for Mother
and Child
IGMC, Shimla, Himachal Pradesh, India
Kusum G Kapoor MD FICOG FICS
Consultant, Obstetrics and Gynecology
Ex Professor and Head, Department of Obstetrics
and Gynecology
Nalanda Medical College Hospital
Patna, Bihar, India

Krishna Kavita Ramavath MD FICOG
Physician Observer Fellow, Gynec-Oncology,
Doctors Hospital, Baptist Hospital
South Florida, Miami, USA
Pratap Kumar MD DGO FICS FIGOG
Professor, Department of Obstetrics and
Gynecology
Kasturba Medical College, Manipal University
Manipal, Karnataka, India
S Shantha Kumari MD
Professor, Obstetrics and Gynecology
Deccan College of Medical Sciences
Hyderabad, Andhra Pradesh, India

Anupam Gupta MS FICMU FICMCH
Consultant, Aakanksha Test Tube Baby Centre
Agra, Uttar Pradesh, India

Kiran Kurtkoti DGO DNB

Kurtkoti Nursing Home
Pune, Maharashtra, India

Sadhana Gupta MS MNAMS FICOG FICMU FICMCH
Senior Consultant, Jeevan Jyoti Hospital and
Medical Research Centre
Gorakhpur, Uttar Pradesh, India

Pooja Lodha DNB Fellow, Fetal Medicine and Fetal Therapy
Lead Consultant
Deparment of Fetal Medicine and Fetal Therapy
Ruby Hall Clinic, Pune, Maharashtra, India


Contributors
Pragya M Choudhary DFFP MRCOG (London) PhD
MICOG

Consultant, Obstetrics and Gynecology
NuLife Test Tube Baby Centre
MGM Hospital and Research Centre
Patna, Bihar, India
Asmita M Rathore MD MRCOG
Director, Professor, Department of Obstetrics and
Gynecology, Maulana Azad Medical College and
LNJP Hospital, New Delhi, India
Nalini Mahajan MD MMedSci (ART FICOG)
Director, Mother and Child Hospital
New Delhi, India
Sujata Misra MD FICOG

Associate Professor, Department of Obstetrics and
Gynecology
SCB Medical College
Cuttack, Odisha, India
Bhavana Mittal FNB, MNAMS, Post Doctoral Fellow in
Reproductive Medicine ART

Consultant, Shivam Surgical and Maternity Centre
Delhi
Pushpanjali Institute of IVF and Infertility
Ghaziabad, Uttar Pradesh, India
Neela Mukhopadhaya MBBS DGO (India) MRCOG (UK)
FIGOG (India) DRMCH (UK)

Consultant, Obstetrics and Gynecology
Luton and Dunstable Teaching Hospital
Lewsey Road, Luton, United Kingdom
Sudhanshu Nanda MD
Consultant, Obstetrics and Gynecology
Cuttack, Odisha, India
Roza Olyai MS MICOG FICMCH FICOG
Director, Olyai Hospital
Gwalior, Madhya Pradesh, India

Ram P Dey MD DCH MICOG
Assistant Professor, Department of Obstetrics and
Gynecology
IPGMER and SSKM Hospital
Kolkata, West Bengal, India
Deepali P Kale DNBE FCPS DGO (MUHS) DGO (CPS)

Assistant Proffessor, Nowrosjee Wadia Maternity
Hospital and Seth GS Medical College
Parel, Mumbai, Maharashtra, India
Bhaskar Pal DGO MD DNB FICOG FRCOG
Senior Consultant, Obstetrics and Gynecology
Apollo Gleneagles Hospital
Kolkata, West Bengal, India
Seetha Ramamurthy Pal DGO MD MRCOG RCOG/RCR
Diploma in Advanced Obstetric Ultrasound

Consultant, Obstetrics and Gynecology
Apollo Gleneagles Hospital
Kolkata, West Bengal, India
Suchitra N Pandit MD DNBE FRCOG FICOG DFP MNAMS:
B Pharm

Consultant, Obstetrics and Gynecology
Kokilaben Dhirubhai Ambani Hospital and
Research Centre
Mumbai, Maharashtra, India
Harshad Parasnis MD DNB FCPS DGO FICOG
Consultant Gynecologic Oncologist
Honorary Associate Professor
Bharati Vidyapeeth Medical College
Pune, Maharashtra, India
Madhuri Patel MD DGO FICOG
Honorary Consultant, N Wadia Maternity Hospital
Mumbai, Maharashtra, India
MC Patel MD
Gynecologist and Medicolegal Counsellor

Niru Maternity and Nursing Home
Ahmedabad, Gujarat, India

xiii


xiv A Practical Guide to First Trimester of Pregnancy
Deepali Patil MD DGO FCPS
Consultant, Obstetrics and Gynecology
Shri Mahalaxmi Nursing Home
Kolhapur, Maharashtra, India
Ameet Patki MD DNB FCPS FICOG FRCOG (UK)
Medical Director, Fertility Associates, Mumbai
Consultant, Obstetrics and Gynecology
Sir Harkisondas Hospital and Research Centre
Hinduja HealthCare Surgicals
Honorary Associate Professor, Obstetrics and
Gynecology
KJ Somaiya Medical College and Hospital
Mumbai, Maharashtra, India
Shashi Prateek MD
Professor and Head, Department of Obstetrics and
Gynecology
Vardhman Mahavir Medical College and
Safdarjung Hospital
New Delhi, India
Reena Rani MBBS
Postgraduate Student (Obstetrics and Gynecology)
Maulana Azad Medical College
New Delhi, India

Aarti Rapol DNB DGO
Assistant Consultant, Pune Fertility Centre
Pune, Maharashtra, India
Rajat Ray MD
Assistant Professor, Hi-Tech Medical College
Rourkela, Odisha, India
Suvarna S Khadilkar MD DGO FICOG
Consultant, Gyne-Endocrinologist
Bombay Hospital and Medical Research Centre
Mumbai, Maharashtra, India

Jayprakash Shah MD FICOG
Rajni Hospital, Ahmedabad
CIMS Hospital, Science City Road, Ahmedabad
Akar IVF Centre Anand, Ahmedabad
Gujrat, India
Parth Shah MD DGO FIGE
Laproscopist and Fetal Medicine Expert
Rajni Hospital
Ahmedabad, Gujrat, India
Shivani Singh MD DNB FNB (Reproductive Medicine)
Associate Consultant, Mother and Child Hospital
New Delhi, India
Sunita Tandulwadkar MD (OBGY) FICS FICOG Dip in
Endoscopy (USA and Germany)

Head of the Department (Obstetrics and
Gynecology), Ruby Hall Clinic
Pune, Maharashtra, India
Sangeeta Tejpuria MD

Consultant, Gynecologist and Infertility Specialist
Rajashree Nursing Home
Nagpur, Maharashtra, India
Ajay V Valia MD
Consultant, Isha Hospital, Krishna Hospital
Vadodra, Gujarat, India
D Vidyadhari MD
Professor, Obstetrics and Gynecology
Mediciti Medical College
Hyderabad, Andhra Pradesh, India


Foreword

Hema Divakar DGO MD FICMCH FICOG PGDMLE
President, FOGSI 2013

Senior Consultant, Divakar Speciality Hospital
JP Nagar, Bengaluru, India
Director, Mediscan Divakar’s Ultrasound Training Program, Bengaluru, India

Eccentricity was once a prized attribute of famous clinicians. However, aberrations in obstetrics such as
use of thalidomide resulting in tens and thousands of children with phocomelia have led to widespread
reluctance on the part of couples to accept bland reassurances from the doctors. In these days of ready
access to internet, one needs to justify one’s choice of management.
Fortunately help is at hand. Dr Mala Arora and Dr Alok Sharma have done a superb job in persuading
top class clinicians to summarize for us topics related to crucial issues in first trimester of pregnancy. This
book is a collection and expansion of the very popular management options, to inform the reader and
guide their practice. Our patients deserve it.
This book on “A Practical Guide to First Trimester of Pregnancy” is an essential read for all clinicians

to help their patients embark on healthy foundations for the journey through a safe pregnancy and
successful outcome. I congratulate Dr Mala Arora and Dr Alok Sharma, and all the authors for providing
practical and insightful information for best practices in managing routine and complex situations in
the first trimester.



Preface

‘’The magical moment of creation of a new life ushers the first trimester’’
It gives us immense pleasure to bring forth this ‘A Practical Guide to First Trimester of Pregnancy’. The
first trimester is fraught with danger, with a 20% risk of losing the fetus during this time. It requires careful
vigilance in patients with assisted conceptions, recurrent miscarriages, advanced maternal age, and
preexisting medical disorders. Events of the first trimester lay the foundation, as well as seal the fate of a
pregnancy. The booking visit is the most crucial visit for the obstetrician and the triaging of antenatal care
is decided in the first trimester. We believe that if the first trimester is handled competently, it can save
many adverse pregnancy outcomes for both, the mother and the baby.
In this issue, we have touched on all relevant aspects of the first trimester where the obstetrician may
need guidance in decision making. First trimester is the platform on which obstetricians, fetomaternal
specialists, endocrinologists, geneticists, sonologists, medical and surgical specialists, dieticians,
endoscopists and IVF specialists converge, to ensure a healthy pregnancy.
This book is a practical guide to management of first trimester and its complications and incorporates
a blend of accepted guidelines, practical inputs and recent advances. On the journey of pregnancy
‘Well Begun is half done!’
Mala Arora
Alok Sharma



Acknowledgments

We are indebted to all the authors for their contribution to this book, who despite their busy schedule
have provided outstanding, up-to-date, and evidence-based chapters on various aspects of first trimester
of pregnancy.
We are especially thankful to Dr Surveen Ghumman who has helped us at the conception of the book
in elaborating and refining the content list.
We wish to thank Mr JP Vij, CEO Jaypee Brothers Medical Publishers for his encouragement in bringing
out this book. The editorial team under the able leadership of Dr Madhu Choudhary has extended
excellent support to me and worked untiringly to shape up this manuscript.
Mala Arora
Alok Sharma



Physiological Changes

1

Chapter

Suvarna S Khadilkar, Deepali Patil

INTRODUCTION
The anatomical, physiological, and hormonal
changes in pregnancy are significant and
occurr in response to stimuli from the placenta
and the fetus. Due to these changes, there are
physiological symptoms in first trimester of
pregnancy. The understanding of these changes
is essential to treat symptomatology of pregnant

woman, and also to know the physiological basis
for certain conditions of pregnancy. For majority
of these complaints, only reassurance may be
enough, but for some therapeutic measures may
have to be undertaken to ensure good maternal
and fetal outcome.
The changes occur in all systems of the body
starting from the first trimester and gradually
increasing toward the last trimester. Major
changes in first trimester occur in the genital
system, gastrointestinal system, cardiovascular
systems, and central nervous system. Systemic
changes, leading to physiological symptoms
in first trimester of pregnancy occur from first
trimester onward (Box 1). The major factors
responsible for the physiological changes in
pregnancy are increasing levels of human
chorionic gonadotropin (hCG), estrogen, and
progesterone.

ch-01.indd 1

Box 1: Physiological symptoms of first trimester of
pregnancy
• Amenorrhea
• Morning sickness
• Giddiness, weakness, and leg cramps
• Drowsiness or excessive sleepiness
• Anorexia
• Headache and heaviness in the head

• Frequency of micturition
• Leucorrhea or excessive vaginal discharge
• Breast discomfort

Genital System
Increased level of progesterone is associated
with increased vascularity of pelvic organs and
decreased vascular resistance. This leads to
congestion of genital organs.1

Uterus
Uterine size is increased both due to intra­uterine
growth of the gestational sac (distension), and
also due to myohyperplasia and hypertrophy of
myometrium under the influence of estrogen.
Progesterone excess is associated with increased
vascularity.

23-01-2014 15:47:24


2 A Practical Guide to First Trimester of Pregnancy
The shape of the pre-pregnant uterus is
pyriform which becomes globular by end of the
first trimester and then it again changes to oval,
from 12 weeks onward. Due to increasing tension
in the growing amniotic sac, there is downward
pressure on the cervix.

Uterine Signs

• Size, shape, and consistency: The uterus is
enlarged to the size of hen’s egg at 6th week,
size of a cricket ball at 8th week, and size of a
fetal head by 12th week. The pyriform shape
of the non-pregnant uterus becomes globular
by 12 weeks. The uterus becomes acutely
anteverted between 6 weeks and 8 weeks.
There may be a symmetrical enlargement
of the uterus if there is lateral implantation.
This is called Piskacek’s sign where one half is
more firm than the other half. As pregnancy
advances, symmetry is restored. The pregnant
uterus feels soft and elastic
• Hegar’s sign: It is present in two-thirds of cases.
It can be demonstrated between 6 weeks and
10 weeks, a little earlier in multiparae. This
sign is based on the fact that: (1) Upper part
of the body of the uterus is enlarged by the
growing fetus, (2) lower part of the body is
empty and extremely soft, and (3) the cervix
is comparatively firm. Because of variation
in consistency, on bimanual examination
(two fingers in the anterior fornix and the
abdominal fingers behind the uterus), the
abdominal and vaginal fingers seem to appose
below the body of the uterus
• Palmer’s sign: Regular and rhythmic uterine
contraction can be elicited during bimanual
examination as early as 4–8 weeks. Palmer in
1949, first described it and it is a valuable sign

when elicited.

Cervix
Congestion and softening of cervix occurs during
early trimester. Non-pregnant cervix has a firm

ch-01.indd 2

feel on touch but, during pregnancy it is soft.
Increased vascularity causes congestion of cervix
giving rise to bluish discoloration of cervix and is
known as Goodell’s sign. During the first trimester,
isthmus elongates to three times original
length and after 12 weeks it unfolds from above
downward. Thus, lower segment starts to form
from the end of the 12th week. If the circular fibers
of the internal os are weak then the abortion takes
place due to incompetent cervix.

Vagina
Vaginal mucosa appears bluish and congested
due to increased vascularization, this leads
to excessive non-purulent vaginal discharge
(physiological leucorrhea). There is increased
pulsation, felt through the lateral fornices at 8th
week called Osiander’s sign. Similar pulsation is,
however, felt in acute pelvic inflammation.

External Genitalia
A dusky view of vestibule and anterior vaginal

wall usually seen in multipare is known as
Chadwick’s or Jacquemier’s Sign and is due to
altered vascularity.

Ovaries
Ovulation ceases during pregnancy and the
maturation of new follicles is suspended. A single
corpus luteum of pregnancy may be found in
the ovary of pregnant women and functions
maximally during the first 6–7 weeks of pregnancy.

Breast
Breast changes are evident in primigravidas.
There is deeper pigmentation of the areola and
nipples are larger and erectile. The breast changes
are evident between 6 weeks and 8 weeks. There
is enlargement with vascular engorgement
evidenced by the delicate veins visible under the
skin. The nipple and the areola (primary) become

23-01-2014 15:47:24


Physiological Changes
more pigmented specially in dark women.
Montgomery’s tubercles are prominent. Thick
yellowish secretion (colostrum) can be expressed
as early as 12th week.

Gastrointestinal System

Morning sickness is a common complaint in the
first trimester and its severity very well correlates
with level of hCG. Relaxation of the cardiac
sphincter of stomach causes regurgitation of food
and leads to recurrent vomiting and retrosternal
burning in early trimester. Under the influence of
progesterone, there is decreased gastrointestinal
motility and a decreased muscle tone of the
intestinal tract which is responsible for anorexia,
indigestion, and constipation during pregnancy.
Liver function is depressed during pregnancy but
there are no changes in the liver function test.
There is delayed emptying of gall bladder.

Urinary System
Enlarged size of the uterus along with its
exaggerated anteverted position leads to
frequency of urine due to bladder irritability.
This may also be due to congestion of the bladder
mucosa.

CARDIOVASCULAR SYSTEM
Effect of hormonal changes on the cardiovascular
system leads to hyperdynamic circulation. There
is relaxation of smooth muscles of vessels leading
to decreased vascular resistance in almost all
vasculature. This effect is measured as overall
fall of diastolic blood pressure and mean arterial
blood pressure by 5–10 mm of Hg. The cardiac
output starts rising since 5 week of pregnancy.2

Blood volume starts rising from 10th week onward.
All these changes in the cardiovascular system
are responsible for complaints like giddiness,
weakness, headache, and heaviness in the head.3

ch-01.indd 3

3

Musculoskeletal System
During early weeks of pregnancy, there is
secretion of relaxin. Under the influence of
relaxin, there is relaxation in joint synovial
membranes leading to instability of synovial
joints like sacroiliac joint and pubic symphysis.
Usually, there is no movement in these joints,
but because of these changes, there is instability
in the pelvis leading to pain in the hips during
walking, and turning while in lying down
position.4 Pregnant women commonly complain
of cramps in the legs and calf muscle pain, which
may be due to decreased availability of energy
resources like adenosine triphosphate.

Central Nervous System
Increased level of hormones may have effect
on central nervous system causing nausea and
vomiting.

Cutaneous Changes

Hyperdynamic circulation in pregnancy leads to
increased vascularity of the skin during pregnancy
and disturbed thermoregulation of the body,
leading to rise in basal body temperature by 1°F.
Due to this, pregnant women complain of heat
intolerance.

Weight
In the first trimester, a woman may lose weight
because of nausea, vomiting, and anorexia

Osmoregulation
During pregnancy, there is increased sodium
retention due to estrogen, progesterone,
aldosterone, and antidiuretic hormone. Increased
accumulation of fluid leads to decrease in colloid
osmotic pressure due to hemodilution.

23-01-2014 15:47:24


4 A Practical Guide to First Trimester of Pregnancy
Metabolism
Initially during the first trimester, there is negative
protein metabolism and lipolysis. Gradually, as
symptoms of early pregnancy subside, protein
synthesis and lipogenesis develop due to estrogen
effect.

Endocrine System

Before the placental function starts corpus luteum
acts as a rescue till 6–8 weeks of pregnancy.
Syncytiotrophoblasts secrete a number of protein
and steroidal hormones that simulate pituitary
hormones.5 Some of the important hormones are:
• Human chorionic gonadotropin: is a glyco­
protien hormone which simulates luteinizing
hormone, plays a major role in maintenance
of pregnancy and immunosuppression. It
stimulates the adrenal and placental steroid­
ogenesis, and maternal thyroid gland
• Human placental lactogen: is lactogenic and
functions as growth hormone in pregnancy
• Human chorionic thyrotropin
• Human chorionic corticotropin
• Steroidal hormones: estrogen and proges­
terone start rising since 9th week of pregnancy.

Table 1: Carnegie stages of embryonic development
Day post­
ovulation

Carnegie
stages

Embryonal development

0

1

Fertilization

1

2

2-cell stage blastomere

2

-

4-cell stage

3

-

12-cell stage

4

-

16-cell stage morula

5

3

Blastocyst

6

4

Interstitial implantation

11

5

Implantation completed

13

6

Primitive streak gastrulation
primary villi

16

7

Secondary villi neurulation

17–19

8

Primitive pit, notochordal
canal, and neurenteric canals

21

9

Appearance of (mesoderm)
tertiary villi somites

22

10

Neural folds/heart folds begin
to fuse fetal heart and fetal
circulation

23–25

11

Two pharyngeal arches
appear

25–27

12

Upper limb buds appear

27–30

13

The first thin surface layer
of skin appears covering the
embryo

31–35

14

Esophagus formation takes
place

35–38

15

Future cerebral hemispheres
distinct

38–42

16

Hindbrain begins to develop

42–44

17

A four chambered heart

44–48

18

Lens vesicle, nasal pit, and
hand plate begins to develop

48–51

19

Semicircular canals forming in
inner ear

51–53

20

Spontaneous movement
begins

Embryonal And Fetal Development
Normal embryonal and fetal development during

first trimester is illustrated in table 1. It is amply
clear that any insult during this phase may cause
first trimester abortion.
Physiological maternal adaptation in
pregnancy starts as soon as conception occurs.
These changes are necessary for implantation
and healthy growth in early pregnancy. The
understanding of these changes and influence
of age, parity, race, multiple gestation, and other
variables has to be understood to appreciate the
adaptations and disease process that occur during
pregnancy.

Contd...

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Physiological Changes

REFERENCES

Contd...

ch-01.indd 5

5

Day post­
ovulation

Carnegie
stages

Embryonal development

53–54

21

Intestines recede into body
cavity

54–56

22

Brain can move muscles,
begins to transform into bone
cartilage

56–60

23

End of embryonic period
(all major structures form
recognizably human)

60–68

-

External genitalia develops

70 days

-

Fetus begins to move

1. Ganong WF. The gonads: development and function of reproduc­
tive system. In: Ganong WF, editor. Review of Medical Physiology.
2nd ed. Philadelphia, PA: McGraw-Hill; 2009. p. 142-7.
2. Pandey AK, Banerjee AK, Das A, et al. Evaluation of maternal
myocardial performance during normal preg­nancy and post
partum. Indian Heart J. 2010;62(1):64-7.
3. McFadyn IR. Maternal changes in normal pregnancy. In:
Turnbull A, Chamberlin G, editors. Obstetrics. 3rd ed. Edinburgh:
Churchill Livingstone; 1994. p. 151-71.
4. Stirrat GM. Physiological changes in pregnancy. In: Stirrat GM,
editor. Obstetrics. 2nd ed. Blackwell Oxford, Boston: Scientific
Publication; 1986. p. 7-22.
5. Roti E, Gnudi A, Braverman LE. The placental transport,
synthesis and metabolism of hormones and drugs which effect
thyroid function. Endocrinal review. 1983;4(2):131-49.

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