pregnancy

Physiology of Physiology of PregnancyPregnancy

Santosh mohleSantosh mohle

BNYSBNYS

SVYASASVYASA

Apr 8, 2023 1

Apr 8, 2023 2

INTRODUCTIONINTRODUCTION

PregnancyPregnancy

The course that the embryo and the fetus The course that the embryo and the fetus grow in the maternal bodygrow in the maternal body

Stages of pregnancyStages of pregnancy

1.1.Early pregnancy: ≤12 weeks Early pregnancy: ≤12 weeks

2.2.Mid pregnancy: ≥13 weeks,≤27 weeks Mid pregnancy: ≥13 weeks,≤27 weeks

3.3.Late pregnancy:≥28 weeksLate pregnancy:≥28 weeks

4.4.Term pregnancy:≥37 weeks,<42 weeks Term pregnancy:≥37 weeks,<42 weeks

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Normal pregnancy average duration is counting from first day of last menstrual period is about 280 days and 10 lunar

months or 40 weeks

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Formation of Embryo Formation of Embryo

A.A. FertilizationFertilization

Fusion of male & female gamates to form Fusion of male & female gamates to form a zygotea zygote

1.1. Place: oviduct (ampulla)Place: oviduct (ampulla)

2.2. ProcessProcess

capacitation → acrosome reaction→ capacitation → acrosome reaction→ penetrate the zona pellucida→ penetrate the zona pellucida→ second meiosis →zygotesecond meiosis →zygote

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FertilizationFertilization

Fertilization in the ampulle of the FT.

Prostaglandins• Oxytocin

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Contd…Contd…

B. ImplantationB. Implantation

1)1)Disappear of zona Disappear of zona pellucidapellucida

2)2)Formation of Formation of syncytiotrophoblastsyncytiotrophoblast3)3)Synchronized development of Synchronized development of blastocyst and endometriumblastocyst and endometrium

4)4)Adequate progesterone Adequate progesterone

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ProcessProcess

1)1) morula (day 3) → enter uterine morula (day 3) → enter uterine cavity (day 4) → early cavity (day 4) → early blastocyst→ late blastocyst blastocyst→ late blastocyst (day 6-7) → implantation(day 6-7) → implantation

2)2) locationlocation→→ adherence adherence→→ penetrationpenetration

Contd…Contd…

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FertilizationFertilizationImplantation 5-7 days after fertilization

• Proteolytic enzymes of the trophoblast cells

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Development of embryo and fetusDevelopment of embryo and fetus

DefinitionDefinition

1.1.embryo: embryo: ≤ ≤ 8 weeks8 weeks

2.2.Fetus: Fetus: ≥≥ 9 weeks, human shape 9 weeks, human shape

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Physiology of fetusPhysiology of fetus

A.A.CirculationCirculation

1)1)fetus ←→placenta←→ materfetus ←→placenta←→ mater

2)2)1 umbilical vein (full of oxygen), 1 umbilical vein (full of oxygen), 2 umbilical artery (lack of oxygen)2 umbilical artery (lack of oxygen)

3)3)Mixed blood (vein and artery)Mixed blood (vein and artery)

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B. HematologyB. Hematology

1)1) ErythropoiesisErythropoiesis

From yolk sac: 3 weeksFrom yolk sac: 3 weeks

From liver: 10 weeksFrom liver: 10 weeks

From bone marrow and spleen: term From bone marrow and spleen: term (90%)(90%)

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2) 2) Fetal hemoglobinFetal hemoglobin

Fetal hemoglobin: early pregnancyFetal hemoglobin: early pregnancy

Adult hemoglobin: 32Adult hemoglobin: 32ndnd week week

Term: fetal type Hb 25%Term: fetal type Hb 25%

3) White cells3) White cells

Leukocytes: 8 weekLeukocytes: 8 week

Lymphocytes (antibody production): 12 Lymphocytes (antibody production): 12 week, thymus and spleenweek, thymus and spleen

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C. C. Gastrointestinal tractGastrointestinal tract

1)1) drink amniotic fluid: 4drink amniotic fluid: 4thth month month

2)2) no proteolytic activityno proteolytic activity

3)3) enzymatic deficiencies in liver: enzymatic deficiencies in liver:

bilirubin is not easy to be clear.bilirubin is not easy to be clear.

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D. KidneyD. Kidney Its function begins at 11-14Its function begins at 11-14thth week week

E. E. EndocrinologyEndocrinology1)1) Fetal thyroid: the first endocrine Fetal thyroid: the first endocrine

gland (6gland (6thth week), synthesize week), synthesize thyroxine at 12thyroxine at 12thth week week

2)2) Fetal adrenal cortex: widen (20Fetal adrenal cortex: widen (20thth week), a fetal zone. synthesize week), a fetal zone. synthesize steroid hormones ( liver placenta steroid hormones ( liver placenta mater)mater)

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Placenta developmentPlacenta development

Early nutrition of the embryo

10th week

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PlacentaPlacenta -- oxygen transportoxygen transport

• Similarities betwen placenta Similarities betwen placenta and lungsand lungs

• Oxygen transport - simple Oxygen transport - simple difusiondifusion

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PlacentaPlacenta

• StructureStructure

1.1. Primary villusPrimary villus

syncytiotrophoblast syncytiotrophoblast cytotrophoblastcytotrophoblast

1.1. Secondary villusSecondary villus

2.2. third class vilusthird class vilus

fetal capillary enter the stromafetal capillary enter the stroma

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PlacentaPlacenta

FunctionFunction

1.1.metabolismmetabolism

1)1)Exchange of OExchange of O22 and CO and CO22

2)2)Exchange of nutritive factors and Exchange of nutritive factors and wastewaste

1.1.DefensiveDefensive

Limited. IgG, virus, drug Limited. IgG, virus, drug

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PlacentaPlacenta

EndocrineEndocrine1)1)Human chorionic gonadotrophicHuman chorionic gonadotrophic2)2)Human placental lactogenHuman placental lactogen

1)1)OxytocinaseOxytocinase2)2)Cytokines and Growth FactorsCytokines and Growth Factors1.1.Immunity toleranceImmunity tolerance

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Fetal membranesFetal membranes

StructureStructure

chorion and amnionchorion and amnion

AmnionAmnion

A double-layered translucent A double-layered translucent membranemembrane

Become distended with fluidBecome distended with fluid

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Umbilical CordUmbilical Cord

StructureStructure

amnion, yolk sac, one vein, two amnion, yolk sac, one vein, two artery and Wharton jellyartery and Wharton jelly

LengthLength

30-70cm30-70cm

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Amniotic fluidAmniotic fluid

SourceSource

1.1.exudation of fetal membranes exudation of fetal membranes (early pregnancy)(early pregnancy)

2.2.Fetal urineFetal urine

3.3.Fetal lungFetal lung

4.4.Exudation of amnion and fetal Exudation of amnion and fetal skinskin

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Cont Cont

• AbsordAbsord

1.1. Fetal membraneFetal membrane

2.2. Umbilical cordUmbilical cord

3.3. Fetal skinFetal skin

4.4. Fetal drinkingFetal drinking• FeatureFeature

1000-1500ml at 361000-1500ml at 36thth-38-38thth week week

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contcont

FunctionFunction

1.1.Protect fetalProtect fetal

move freely, warmmove freely, warm

1.1.Protect materProtect mater

prevent infectionprevent infection

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Fetal physiology - Fetal physiology - circulationcirculationFetal heart rate (FHR) – beating at 5 weeks –Fetal heart rate (FHR) – beating at 5 weeks –

100 beats/min100 beats/min 8 weeks – 160 beats/min8 weeks – 160 beats/min 15 weeks – 150 beats/min15 weeks – 150 beats/min Birth – 130 beats/minBirth – 130 beats/min Bradycardia – slow pulse rate – veryBradycardia – slow pulse rate – very dangerous to fetusdangerous to fetusBlood flow – 40% to head/upperbodyBlood flow – 40% to head/upperbody 30% to placenta30% to placenta 30% to lower body30% to lower body

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Fetal circulation

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Fetal Physiology - RespirationFetal Physiology - Respiration

Gross breathing movements at 11 weeks Rapid Gross breathing movements at 11 weeks Rapid and irregular – associated with REMand irregular – associated with REM

(rapid eye movements)(rapid eye movements) Isolated slow movements – gaspsIsolated slow movements – gasps

Function of fetal breathing:Function of fetal breathing: Stimulates growth of the lungsStimulates growth of the lungs Conditioning of musclesConditioning of muscles

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The First TrimesterThe First TrimesterLasts from conception to the twelfth week of pregnancyLasts from conception to the twelfth week of pregnancy3periods during the first trimester:3periods during the first trimester:

– The Germinal PeriodThe Germinal Period• Fertilized egg travels and implants in wall of uterusFertilized egg travels and implants in wall of uterus• Implantation occurs 10-14 days after conceptionImplantation occurs 10-14 days after conception

– The Period of the EmbryoThe Period of the Embryo• Lasts from third through 8th week of pregnancyLasts from third through 8th week of pregnancy• Major organs and anatomical structures begin to formMajor organs and anatomical structures begin to form

– The Period of the FetusThe Period of the Fetus• Lasts from ninth week of pregnancy until birth Lasts from ninth week of pregnancy until birth • All major organs continuAll major organs continu

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The Second TrimesterThe Second Trimesterweek 13-29week 13-29

Fetus assumes distinct human appearanceFetus assumes distinct human appearance

• The nails harden and skin thickens, as well The nails harden and skin thickens, as well as the eye lashes, eye brows, and scalp hair as the eye lashes, eye brows, and scalp hair appear during fifth and sixth monthsappear during fifth and sixth months

• Fetus’s visual and auditory senses are Fetus’s visual and auditory senses are functional functional

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The Third TrimesterThe Third Trimesterweek 29to 40week 29to 40

All organ systems mature rapidlyAll organ systems mature rapidly

• Fetus prepares for birthFetus prepares for birth• Fetus reaches ‘age of viability’, the point at which the Fetus reaches ‘age of viability’, the point at which the

fetus can survive outside of the uterusfetus can survive outside of the uterus• Fetus shows better-organized gross motor activity, and Fetus shows better-organized gross motor activity, and

sleepiness/ waking activitysleepiness/ waking activity• Towards end of ninth month, fetus is positioned head-Towards end of ninth month, fetus is positioned head-

down with limbs curled up in ‘fetal position’down with limbs curled up in ‘fetal position’

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Physiologic changes in pregnant womanPhysiologic changes in pregnant woman

• Genital organsGenital organs1.1. UterusUterus1)1) capacity: 5ml-5000ml.weight: 50g-capacity: 5ml-5000ml.weight: 50g-

1000g1000g2)2) Hypertrophy of muscle cellsHypertrophy of muscle cells3)3) EndometriumEndometrium→→decidua: basal decidua: basal

decidua, capsular decidua, true decidua, capsular decidua, true deciduadecidua

4)4) Contraction: Braxton HicksContraction: Braxton Hicks5)5) Isthmus uteri: 1cmIsthmus uteri: 1cm→→ 7-10cm 7-10cm

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1)1) Cervix: coloredCervix: colored

2)2) Ovary: placenta replaces ovary (10Ovary: placenta replaces ovary (10thth week)week)

3)3) Vagina: dilated and soft, pHVagina: dilated and soft, pH↓↓(anti-(anti-bacteri bacteria)bacteri bacteria)

4)4) Ligaments: relaxedLigaments: relaxed

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Changes in the shape of the Changes in the shape of the uterusuterus

• Isthmus elongates during the 1Isthmus elongates during the 1stst 10 weeks like a stalk10 weeks like a stalk

• From 7mm to 2.5cms at 10 weeksFrom 7mm to 2.5cms at 10 weeks

• Later becomes the lower Later becomes the lower segment with the globular uterus segment with the globular uterus sitting on topsitting on top

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BLOOD SUPPLY TO UTERUSBLOOD SUPPLY TO UTERUS

• Blood supply pre pregnancy = Blood supply pre pregnancy = 10mls/min10mls/min

• At 40weeks 800 – 900mls/minAt 40weeks 800 – 900mls/min

• 20% of cardiac output goes to 20% of cardiac output goes to uterusuterus

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88thth week week

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1212thth week week

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1616thth week week

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2020thth week week

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2424thth week week

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3030thth week week

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3636thth week week

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The urinary systemThe urinary system1.1.KidneyKidney1)1)Renal plasma flow (RPF):Renal plasma flow (RPF):↑↑35%35%2)2)Glomerular filtration rate (GFR):Glomerular filtration rate (GFR):↑↑ 50% 50%1.1.UreterUreter Dilated (Dilated (↑↑))1.1.BladderBladder Frequent micturationFrequent micturation

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Cardiovascular systemCardiovascular system1.1.Heart:Heart: move upward, hypertrophy of move upward, hypertrophy of cardiac musclecardiac muscle1.1.Cardiac Output Cardiac Output increase by 30%, reach to peak at increase by 30%, reach to peak at 3232ndnd –34 –34thth week week1.1.Blood pressureBlood pressure early or mid pregnancy Bpearly or mid pregnancy Bp↓.↓.late late pregnancy Bp↑ .Supine hypotensive pregnancy Bp↑ .Supine hypotensive syndromesyndrome

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HematologyHematology1.1. Blood volumeBlood volume1)1) Increase by 30%-45% at 32Increase by 30%-45% at 32ndnd –34 –34thth

(peak)(peak)2)2) Relatively dilutedRelatively diluted1.1. CompositionComposition1)1) Red cellsRed cells Hb:130Hb:130→→110g/L, HCT:38%110g/L, HCT:38%→→ 31%. 31%.1)1) White cells: slightly increaseWhite cells: slightly increase2)2) Coagulating power of blood: Coagulating power of blood: ↑↑ 3)3) Albumin: Albumin: ↓,↓,35 g/L35 g/LApr 8, 2023 48

Hematologic changesHematologic changes

•plasma volume increases (50%)•erythropoesis (RBC) increases (25%)

• decreased Hb, hematocrite

• Iron requirements increases significantly• Iron suplements needed

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The Respiratory systemThe Respiratory system

1.1. R rate: slightly R rate: slightly ↑↑

2.2. vital capacity: no changevital capacity: no change

3.3. Tidal volume: Tidal volume: ↑↑ 40% 40%

4.4. Functional residual capacity:Functional residual capacity:↓↓

5.5. OO22 consumption: consumption: ↑↑ 20% 20%

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• Gastrointestinal systemGastrointestinal system

1)1) Gastric emptying time is Gastric emptying time is prolongedprolonged→→ nausea. nausea.

2)2) The motility of large bowel is The motility of large bowel is diminished diminished →→ constipation constipation

3)3) Liver function: unchanged Liver function: unchanged

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Increases in body weightIncreases in body weight

The average weight gained by the body The average weight gained by the body during pregnancy in about 12 kg the during pregnancy in about 12 kg the approximate weight of various structures approximate weight of various structures which adds to the weigth gain which adds to the weigth gain

fetus : 3.5kg fetus : 3.5kg

Amniotic fluid : 2.0 kg Amniotic fluid : 2.0 kg

Placenta : 1.5 kg Placenta : 1.5 kg

Increases in matt. 5.0 kg Increases in matt. 5.0 kg Apr 8, 2023 52

Hormonal changesHormonal changes

Placenta motherPlacenta motherC R H C R H ACTHACTH

aldosteronecortisol

hypertensionedemainsulin resistance

gestational diabetes

HCGHC thyrotropin hyperthyroidism

↑Calcium demands

Hyperparathyroidism

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CHANGES ARE DUE TOCHANGES ARE DUE TO

• ALTERATIONS INALTERATIONS IN

• HORMONAL PRODUCTIONHORMONAL PRODUCTION

• CIRCULATIONCIRCULATION

• METABOLISMMETABOLISM

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HORMONESHORMONES

OESTROGENOESTROGEN

• Produced in corpus luteumProduced in corpus luteum

• Produced by placenta after 12 weeksProduced by placenta after 12 weeks

• Responsible for growth particularly of Responsible for growth particularly of uterus and breastsuterus and breasts

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progesteroneprogesterone

• Produced in corpus luteum and then the Produced in corpus luteum and then the placentaplacenta

• Relaxes smooth muscleRelaxes smooth muscle

• Inhibits uterine contractions until uterus is Inhibits uterine contractions until uterus is prepared for labourprepared for labour

• Regulates storage of body fatRegulates storage of body fatApr 8, 2023 56

Human chorionic gonadotrophicHuman chorionic gonadotrophic

• Secreted from trophoblast of the Secreted from trophoblast of the developing embryodeveloping embryo

• Maintains corpus luteum until Maintains corpus luteum until placenta takes overplacenta takes over

• Used in tests to confirm pregnancyUsed in tests to confirm pregnancy

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Human placental lactogenHuman placental lactogen

• Alters maternal metabolismAlters maternal metabolism

• Diverts glucose to fetusDiverts glucose to fetus

• Mobilises free fatty acids from Mobilises free fatty acids from maternal storesmaternal stores

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RELAXINRELAXIN

• Released by corpus luteum then Released by corpus luteum then the Placentathe Placenta

• Softens pelvic ligamentsSoftens pelvic ligaments

• Reduces myometrial tone Reduces myometrial tone

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Changes in the reproductive system: Changes in the reproductive system: UterusUterus

• endometrium ………….decidua endometrium ………….decidua • becomes more vascular and thicker due to becomes more vascular and thicker due to

oestrogen and progesteroneoestrogen and progesterone• decidua provides glycogen rich enviroment decidua provides glycogen rich enviroment

to nourish fetus until trophoblastic cells to nourish fetus until trophoblastic cells develop into placentadevelop into placenta

• decidual cells produce prolactin and relaxin decidual cells produce prolactin and relaxin

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MYOMETRIUMMYOMETRIUM

• Smooth muscle fibres embedded Smooth muscle fibres embedded in a matrix of connective tissuein a matrix of connective tissue

• Grow 15 – 20 times normal sizeGrow 15 – 20 times normal size

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PERIMETRIUMPERIMETRIUM

• Stretches with uterus upwards and Stretches with uterus upwards and outwardsoutwards

• Can cause discomfortCan cause discomfort

• Spasm of broad ligament specially on Spasm of broad ligament specially on right side due to right uterine obliquityright side due to right uterine obliquity

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changes in sizechanges in size

uterus grows to 30x23x20 at termuterus grows to 30x23x20 at termweight increases to 900gmsweight increases to 900gms

hypertrophy.. Oestrogen causes cells hypertrophy.. Oestrogen causes cells to increase until 20 weeks gestationto increase until 20 weeks gestation Hyperplasia:- number of cells increase Hyperplasia:- number of cells increase under the influence of oestrogenunder the influence of oestrogen..

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After 20 weeks gestationAfter 20 weeks gestation

• Uterine muscle tissue stretches Uterine muscle tissue stretches to allow fetus to growto allow fetus to grow

• Progesterone relaxes the smooth Progesterone relaxes the smooth muscles enabling it to stretchmuscles enabling it to stretch

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Changes in the cervixChanges in the cervix

• Length remains the sameLength remains the same• Increase in widthIncrease in width• Softening after third month due to Softening after third month due to

oestrogenoestrogen• Increased vascularityIncreased vascularity• Increased cervical mucosaIncreased cervical mucosa• Increased glandular function Increased glandular function

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BY 12 WEEKSBY 12 WEEKS

• Uterus is upright and leans Uterus is upright and leans slightly to the rightslightly to the right

• No longer a pelvic organNo longer a pelvic organ

• Uterus may be palpable above Uterus may be palpable above the pubic bonethe pubic bone

• Fetus now occupies most of the Fetus now occupies most of the uterine cavityuterine cavity

• Placenta now developedPlacenta now developedApr 8, 2023 66

BLOOD CHANGESBLOOD CHANGES

• Increase in oestrogen: Increase in oestrogen:

new blood vessels formednew blood vessels formed

growth of existing onesgrowth of existing ones

• Therefore an increase in blood Therefore an increase in blood volume.volume.

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• Blood volume: from 5 litres to 7.5Blood volume: from 5 litres to 7.5

total volume up by 40-50%total volume up by 40-50%

• Red cell mass: rises constantly Red cell mass: rises constantly throughout pregnancy Up by 20% by end throughout pregnancy Up by 20% by end of pregnancyof pregnancy

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PLASMA VOLUMEPLASMA VOLUME

Increases from 10Increases from 10thth week of pregnancy week of pregnancy

variable related to parity, fetal weight variable related to parity, fetal weight and numberand number

Reaches maximum level approx 50% Reaches maximum level approx 50% above non-pregnant levels at 32-34 above non-pregnant levels at 32-34 weeks then maintainedweeks then maintained

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Month nineMonth nine

• Lightening – Fetus descends to pelvic cavityLightening – Fetus descends to pelvic cavity• Cervix – Dilation, Effacement (softening,Cervix – Dilation, Effacement (softening,• thinning)thinning)• False Labor – Contractions initiate thenFalse Labor – Contractions initiate then• diminishdiminish• Labor:Labor:• Cervical effacement – dilation to 10 cmCervical effacement – dilation to 10 cm• Bloody Show – mucus plug of the cervix – blood-coloredBloody Show – mucus plug of the cervix – blood-colored• Breaking Water Bag – rupturing of the amnionBreaking Water Bag – rupturing of the amnion• Contractions – shorter intervals, longer, strongerContractions – shorter intervals, longer, stronger

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Uterine ContractionUterine Contraction• Uterine musculature becomes progressively more excitableUterine musculature becomes progressively more excitable• Estrogen/progesterone ratio changes increases excitabilityEstrogen/progesterone ratio changes increases excitability• Progesterone inhibits contractionProgesterone inhibits contraction• Estrogen increases gap junctional communication betweenEstrogen increases gap junctional communication between• smooth muscle cells smooth muscle cells increases contractility increases contractility• Oxytocin (maternal posterior pituitary gland) increases Oxytocin (maternal posterior pituitary gland) increases

excitabilityexcitability• Mechanically stretching uterine smooth muscle increasesMechanically stretching uterine smooth muscle increases• contractilitycontractility• Cervical stretching elicits uterine contractionsCervical stretching elicits uterine contractions• Fetal effects –glucocorticoidsFetal effects –glucocorticoids placentaplacenta inhibits inhibits

progesteroneprogesterone• Fetal oxytocin is also producedFetal oxytocin is also produced

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Labor and ParturitionLabor and ParturitionParturition: Process by which theParturition: Process by which the•baby is bornbaby is born•Labor: Strong uterine contractions,Labor: Strong uterine contractions,•Cervix stretching, Forcing theCervix stretching, Forcing the•fetus through the birth canalfetus through the birth canal•Rhythmic strong uterine contractions expel the fetusRhythmic strong uterine contractions expel the fetus•Positive-Feedback regulation of laborPositive-Feedback regulation of labor•Contractions push baby Contractions push baby stretch cervix stretch cervix•Stretched cervixStretched cervix Stronger uterine contraction Stronger uterine contraction•Cycles until parturition is completeCycles until parturition is complete

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contdcontd

• Contractions: 30 minutes Contractions: 30 minutes 1-3 minutes 1-3 minutes• Contractions strongest at top of uterus – forcing babyContractions strongest at top of uterus – forcing baby• toward cervix (25 lbs/contraction)toward cervix (25 lbs/contraction)• Continuous contractions (tetanus) can stop blood flow andContinuous contractions (tetanus) can stop blood flow and• lead to death of the babylead to death of the baby

• First stage of laborFirst stage of labor: cervical dilation (8-24 hours): cervical dilation (8-24 hours)

• Second stage of laborSecond stage of labor: passage through birth canal : passage through birth canal (few minutes to half hour)(few minutes to half hour)

• Third stage of laborThird stage of labor: expulsion of the placenta: expulsion of the placenta

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After BirthAfter Birth

• 10-45 minutes after parturition the placenta is10-45 minutes after parturition the placenta is• DeliveredDelivered

Separation and ExpulsionSeparation and Expulsion

SeparationSeparation - Uterine cavity reduces in size - Uterine cavity reduces in size • shearing the placenta from the uterine wallshearing the placenta from the uterine wall

Limited bleeding Limited bleeding – controlled by local production– controlled by local production• of vasoconstrictors (prostaglandins)of vasoconstrictors (prostaglandins)• Expulsion is by uterine contractionExpulsion is by uterine contraction

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Conditions During Conditions During PregnancyPregnancy• ConstipationConstipation

– Affects half of pregnant womenAffects half of pregnant women– Causes: Causes:

• increase in progesterone increase in progesterone • the colon absorbing more water the colon absorbing more water • worse in first 13-14 weeksworse in first 13-14 weeks

– Treatment: Treatment: • Drink plenty of fluidsDrink plenty of fluids• Eat high fiber foodsEat high fiber foods• Take fiber supplements – psylium husks, Take fiber supplements – psylium husks,

Metamucil, Ex-LaxMetamucil, Ex-Lax

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Cardiovascular change Cardiovascular change

• Displaced to left and upward Displaced to left and upward • Apex is move laterallyApex is move laterally• Apparent cardiomegarty on chest x- ray Apparent cardiomegarty on chest x- ray • Increase of left ventricular end diastolic Increase of left ventricular end diastolic

dimension dimension • increase of left ventricular wall mass c/w increase of left ventricular wall mass c/w

mild hypertrophy increase in preload mild hypertrophy increase in preload increase increase

capacitance of the systemic pulmonary capacitance of the systemic pulmonary vascular resistance pregnant rise to cvp vascular resistance pregnant rise to cvp or wedge pressure or wedge pressure

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Nausea and Vomiting duringNausea and Vomiting duringPregnancy (NVP)Pregnancy (NVP)(Morning Sickness)(Morning Sickness)

• • Peaks during the first TrimesterPeaks during the first Trimester

• • Positive correlation with birth weightPositive correlation with birth weight

• • Negative correlation with spontaneous Negative correlation with spontaneous abortionsabortions

• • Nausea – 50-70% of pregnant womenNausea – 50-70% of pregnant women

• • Vomiting – 40-50% of pregnant womenVomiting – 40-50% of pregnant women

• • Less than 2% is solely in the morningLess than 2% is solely in the morning

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BreastBreastDevelopmentDevelopmentPregnancyPregnancyHormone-Dependent GrowthHormone-Dependent GrowthEstrogenEstrogenGrowth HormoneGrowth HormoneProlactinProlactinAdrenal glucocorticoidAdrenal glucocorticoidInsulinInsulin• Growth and branching of the ductal systemGrowth and branching of the ductal systemFat DepositionFat Deposition• Progesterone: Final stages – synergistic with Progesterone: Final stages – synergistic with

other hormones – growthof lobules, budding of other hormones – growthof lobules, budding of alveoli, secretory characteristics, but not secretionalveoli, secretory characteristics, but not secretion

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LactationLactation

Prolactin:Prolactin: Promotes milk secretion Anterior Promotes milk secretion Anterior

pituitarypituitaryHypothalamus (inhibition)Steady rise Hypothalamus (inhibition)Steady rise

week 5 – birth stimulates week 5 – birth stimulates colostrum – low volume, no fatcolostrum – low volume, no fat

birth – sudden drop in Estrogen and birth – sudden drop in Estrogen and Progesterone1-7 days prolactin Progesterone1-7 days prolactin induces high milk productioninduces high milk production

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Cont Cont

Other hormones are required: Other hormones are required: growth hormone, cortisol, parathyroid growth hormone, cortisol, parathyroid

hormonehormoneProlactin production is Prolactin production is stimulated by signals from the nipple to stimulated by signals from the nipple to

hypothalamus(repression of prolactin- hypothalamus(repression of prolactin- inhibiting hormone) inhibiting hormone) Anterior Pituitary Anterior Pituitary 10-20x surge of prolactin10-20x surge of prolactin

Nursing can continue for yearsNursing can continue for yearsOnce nursing stops - milk production Once nursing stops - milk production

declines within a weekdeclines within a week

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Milk LetdowMilk Letdow

Milk secreted into the alveoli of the breast, but Milk secreted into the alveoli of the breast, but must be ejected to the ductal system.must be ejected to the ductal system.

Oxytocin (posterior pituitary) stimulates this reflexOxytocin (posterior pituitary) stimulates this reflexOxytocin production controlled by hypothalamus Oxytocin production controlled by hypothalamus

(direct innervation of the posterior pituitary (direct innervation of the posterior pituitary gland)gland)

Oxytocin induces contraction of myoepithelial Oxytocin induces contraction of myoepithelial cellscells

around the alveoliaround the alveoliOxytocin induced by suckling and also cryingOxytocin induced by suckling and also crying

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BREAST FEEDING FEEDBACK BREAST FEEDING FEEDBACK LOOPLOOP

– suckling of baby stimulates nerves in the suckling of baby stimulates nerves in the areola of breast areola of breast

– this stimulates the pituitary to release this stimulates the pituitary to release prolactin and oxytocin prolactin and oxytocin

– the prolactin initiates milk production and the prolactin initiates milk production and moves milk into ducts moves milk into ducts

– oxytocin causes weak contractions in the oxytocin causes weak contractions in the breast to move the milk breast to move the milk

– oxytocin also causes weak contractions in oxytocin also causes weak contractions in the uterus to return the uterus to its normal the uterus to return the uterus to its normal size and shape, thus breast-feeding mothers size and shape, thus breast-feeding mothers regain uterine muscle control quickerregain uterine muscle control quicker

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• Hear baby cry Hear baby cry release oxytocin release oxytocin start to start to move milk "milk let down“move milk "milk let down“

• Stress à lowers milk release Stress à lowers milk release lots of milk lots of milk no release no release increased pressure increased pressure pain (thus pain (thus it is important to be relaxed and in a quiet area it is important to be relaxed and in a quiet area to feed) to feed)

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SFCC: Figure 14.14

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During Lactation Don’tDuring Lactation Don’t::

• Don’t drink alcoholDon’t drink alcohol

• Don’t take medications unless OK by Don’t take medications unless OK by Medical ProviderMedical Provider

• Don’t take illegal drugsDon’t take illegal drugs

• Don’t smokeDon’t smoke

• Don’t get into environmental Don’t get into environmental contaminantscontaminants

• Don’t have caffeineDon’t have caffeine

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Yoga for pregnancyYoga for pregnancy

• Help with breathing and relaxationHelp with breathing and relaxation

• Promote feelings of well-beingPromote feelings of well-being

• EnergizingEnergizing

• Stress reliefStress relief

• Improve posture Improve posture

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Yoga for pregnancyYoga for pregnancy

• Control of excess weight gainControl of excess weight gain• Appearance Improved sleepAppearance Improved sleep• Decreased back pain Decreased back pain • Decreased water retentionDecreased water retention• decrease in complications during decrease in complications during

labourlabour• Shortened labourShortened labour

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SwimmingSwimming

• Uses large muscle groups of the Uses large muscle groups of the legs and armslegs and arms

• No strain on ligaments No strain on ligaments

• Feeling of weightlessnessFeeling of weightlessness

• Improved circulationImproved circulation

• Water Temp 18-25 °CWater Temp 18-25 °C

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Disadvantages of Not Yoga Disadvantages of Not Yoga practicepractice

• Studies have shown that women Studies have shown that women who yoga practice do not who yoga practice do not experience an increase in:experience an increase in:– Premature Rupture of Membranes Premature Rupture of Membranes

(PROM)(PROM)• When the membranes that hold the When the membranes that hold the

amniotic fluid break too early.amniotic fluid break too early.

– Congenital AbnormalitiesCongenital Abnormalities

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Exercises to Avoid During Exercises to Avoid During PregnancyPregnancy

• Ball sportsBall sports• Contact sports: ultimate fighting, wrestling, footballContact sports: ultimate fighting, wrestling, football• Sports that involve bouncing, leaping, a sudden Sports that involve bouncing, leaping, a sudden

change of direction (increased joint laxity from change of direction (increased joint laxity from hormones make joints susceptible to sprains)hormones make joints susceptible to sprains)

• Exercises that put you at risk for falls: rollerblading, Exercises that put you at risk for falls: rollerblading, horseback ridding, skiinghorseback ridding, skiing

• After 1st trimester avoid exercise in the supine After 1st trimester avoid exercise in the supine position position

• Lying in the prone positionLying in the prone position• Lifting heavy free weights Lifting heavy free weights

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Contraindications to ExerciseContraindications to Exercise

• Premature rupture of membranesPremature rupture of membranes• Preterm labor during the prior or current pregnancyPreterm labor during the prior or current pregnancy• Persistent 2nd or 3rd trimester bleedingPersistent 2nd or 3rd trimester bleeding• conditions such as: conditions such as:

– Cardiac disease, constrictive lung diseaseCardiac disease, constrictive lung disease– Chronic hypertensionChronic hypertension– Severe anemia Severe anemia – Chronic bronchitisChronic bronchitis– Extreme obesityExtreme obesity– Extreme underweightExtreme underweight– History of an extremely sedentary lifestyleHistory of an extremely sedentary lifestyle– Orthopedic limitationsOrthopedic limitations– Heavy smokerHeavy smokerApr 8, 2023 91

And Finally…And Finally…

THANK YOUApr 8, 2023 92

pregnancy

Education

early pregnancy

late pregnancy

term pregnancy

mid pregnancy