3.1a Physiological Adaptations to Pregnancy Flashcards
1
Q
Uterus Size, Shape, Position
A
- Uterine growth during first trimester do to progesterone and estrogen
- Early enlargement includes vascularity, hyperplasia, hypertrophy and development of decidua
- Uterus rises in the abdomen as it grows and rotates to the right (due to rectosigmoid colon)
- Discomfort may occur with ligament tension during growth of uterus
2
Q
Hegar’s Sign (6 weeks)
A
- 6 weeks of gestation
- Softening and compressibility of lower uterine segment (Uterine Ishtimus)
3
Q
12 Weeks of Gestation
A
- Uterus changes in shape from pear to spherical
- Uterus rises in pelvis to the abdominal cavity
4
Q
14th Week of Gestation
A
- This is when pregnancy “shows”
- Uterus can be palpated above the symphysis pubis gradually to the level of the umbilics
5
Q
20-22 weeks of getstation
A
- Uterus should be palpable from the xiphoid process at term
6
Q
Lightning (30-38 weeks)
A
Fetus begins to descend to the pelvis
Nullipara - Occurs 2 weeks before the onset of labor
Multipara - Occurs at the start of labor
7
Q
Braxton Hicks Contractions (4th month of pregnancy)
A
- Intermittent uterine contractions may be felt through the abdominal wall
- Enhances blood flow through the intervillous spaces
- Irregular and painless
- After 28th week they become more definite and usually cease with walking or exercise
8
Q
Uterine Souffle
A
- You may hear this sound when auscultating the fetal heart tones
- Similar to a bruit, this sound will be synchronized with mother’s heart beat
9
Q
Funic Souffle
A
- Synchronous with fetal heart rate
- Caused by fetal blood coursing through the umbilical cord
10
Q
Ballottement (16th-18th week)
A
- Passive movement of unengaged fetus
- Identified by examiner
- Practitioner places finger within the vagina taps upward on the cervix causing the fetus to rise
- The fetus can be felt moving up and down.
11
Q
Quickening (14-16th Week)
A
- First recognizable movement of fetus
- Difficult to distinguish from peristalsis
12
Q
Goodell Sign (Beginning of 6 weeks)
A
- Softening of the cervical tip due to increased vascularity, slight hypertrophy, and hyperplasia
13
Q
Friability
A
- Tissue is easily damaged and can result in slight bleeding after vaginal examination or coitus
- Glands near the external OS proliferate and cervix looks velvety
14
Q
Operculum
A
- Mucus fills the endocervical canal resulting in formation of a mucus plug early in pregnancy
- Accuracy of pap tests can also be complicated
15
Q
Changes in Ovaries
A
- Ovulation does not occur during pregnancy due to suppression of follicle stimulating hormone (FSH) and luteinizing hormone (LH) by estrogen and progesterone
- Corpus luteum produces estrogen and progesterone for the first 6-10 weeks and then the placenta becomes the primary source of these hormones
- Menstrual periods cease (amenorrhea)
- Periods can be confused with implantation bleeding which occurs 6-12 days after conception
16
Q
Changes to vagina
A
- Vaginal mucosa thickens
- Connective tissue loosens
- Hypertrophy of smooth muscle
- Vaginal vault lengthens
17
Q
Chadwick Sign (6-8th week of pregnancy)
A
- Increase vascularity results in blue color of vaginal mucosa and cervix
18
Q
Leukorrhea
A
- White/Gray mucoid vaginal discharge with musty odor
- Odor due to microbiome changing and secretions become more acidic
- Alterations help prevent bacterial infections in the uterus
19
Q
Changes to the Breast
A
- Increased levels of estrogen and progesterone make breasts feel heavier and heightened sensitivity
- Sensitivity varies from tingling to sharp pain
- Nipples become more pigmented and erectile
- Stretch marks may appear
20
Q
Prolactin
A
- Produced by anterior pituitary gland
- Stimulates production of colostrum by end of first trimester
21
Q
Montgomery Tubercles
A
- Hypertrophy occurs
- Sebaceous glands secrete lubricating anti-infectives to protect the nipple during breast feeding
22
Q
Lactogenesis Stage 1
A
- Human placental lactogen stimulates secretion of colostrum
23
Q
Changes in blood Volume
A
- Total blood volume increases 40-50%
- Increased blood is protective mechanism
- Meet the blood volume needs of the enlarged uterus
- Hydrates fetal and maternal tissue when the woman assumes an erect or supine position
24
Q
Cardiac Output
A
- Increases by 30-50%
25
Blood Pressure
- Influenced by age, activity level, presence of health problems, circadian rhythm, alcohol consumption, smoking, anxiety, pain, and maternal position
26
Supine Hypotensive Syndrome (Inferior Vena Cava Compression Syndrome)
- Happens when pregnant women lie on their back during second half of pregnancy
- This compresses the vena cava
- CO reduced by 25-30%
- Can experience falls in blood pressure up to 30 mmHg
- After 5 minutes bradycardia is noticed and CO is reduced by half. Women feel faint
27
Structural Adaptations
- Cardiac Hypertrophy
- Diaphragm is displaced upward because of enlarged uterus
- Heart is elevated upward
- Apical pulse shifts up and laterally 1-1.5cm
- Maternal heart rate increases at 5 weeks gestation (15-20bmp)
28
Changes in Blood Components
- RBC mass increases by 20-30%
- Percentage of RBC depends on iron available
- Plasma increase is greater than RBC production
- Decrease in normal hemoglobin and hematocrit values
29
Anemia That Occurs with Pregnancy
- Vitamin B12 deficiency, folate-deficiency anemia, iron deficiency anemia
- Iron deficiency anemia is the most common
- Iron deficiency anemia can lead to low birth weight, premature birth, preeclampsia, and postpartum hemorrhage
- Signs of anemia include weakness, fatigue, headaches, dizziness, pale or sallow skin, low body temperature, rapid or irregular heartbeat, chest pain, shortness of breath, brittle nails and pica.
- Best way to prevent anemia is proper nutrition
- Iron rich foods include red meat, dark green leafy vegetables, eggs, peanuts, fortified cereals etc
- Folate-Deficiency Anemia can lead to neural tube defects (fetal brain and spinal cord anomalies) including spina bifida and anencephaly
30
Respiratory Rate during Pregnancy
- Unchanged to slightly increased
31
Tidal Volume for Respirations
- Increased by 40%
32
Vital Capacity
- Unchanged
33
Inspiratory Capacity
- Increased by 6%
34
Expiratory Reserve Volume
- Decreased by 20%
35
Total Lung Capacity
- Unchanged to slightly decreased
36
Minute Ventilation
- Increased 30-50%
37
Nausea and Vomiting
- Up to 70% of pregnant women experience nausea
- Etiology is unknown but may be high levels of hCG and estradiol, psychological predisposition, evolutionary adaptation to protect fetus from dangerous foods
- Appears 4-6 weeks and peaks around 9 weeks. Subsides by end of first trimester
- See doctor if lasts beyond first trimester or accompanied by fever/weight loss
PICA - Non-food cravings and can be due to iron deficiency anemia
38
-Changes in Mouth, Esophagus, Stomach, Intestines
- Gums become hyperemic and bleeds due to high estrogen
- Increased progesterone slows motility of GI tract and stomach
- Increased progesterone and slowed peristalsis can also cause constipation
(Can also be caused by iron supplements, lack of fluid, decreased activity, antiemetic medication, abdominal distension, displacement and compression of intestines)
- Iron absorbed more readily in small intestines
39
Ptyalism
- Excessive salivation due to decreased swallowing from nausea
40
Epulis (Gingival Granuloma)
- Red nodules on gums that bleed easily
41
Pyrosis
- Acid Indigestion, heartburn.
| - Begins in first trimester and intensifies through the 3rd trimester
42
Hiatal Hernia
- Due to upward displacement of stomach by enlarged uterus
| - Widens hiatus of diaphragm
43
Changes in Gallbladder/Liver
- Gallbladder is distended due to decreased muscle tone in pregnancy
- Increased emptying time of gallbladder
- Hypercholesterolemia due to increased progesterone which can lead to gallstones
- Liver size is unchanged
- Serum albumin and total protein reduced (hemodilution)
- Serum Alkaline Phosphates increased up to 4x
44
Intrahepatic Cholestasis
- May occur in late pregnancy due to placental steroids
- Retention and accumulation of bile
- May cause severe itching with/without jaundice
45
Changes in Abdomen
Intrabdominal Alterations
- Pelvic heaviness or pressure
- Round ligament tension
- Flatulence
- Distension
- Bowel Cramping
- Uterine Contractions
- Venous pressure in pelvic organs due to expanding uterus
46
Appendicitis
- Difficult to diagnose in pregnancy because appendix is displaced upward and laterally
- High and to the right away from McBurney's point
47
Changes in Renal Structure
- Changes result from hormonal activity of estrogen and progesterone
- Kidneys enlarge
- Larger volume of urine held in pelvis
- Urinary stasis
- Higher susceptibility to UTI due to urinary stasis and stagnation
- Urinary frequency and urgency are common
- Bladder capacity increases to 1500 mL
- Bladder compressibility causes urge to void even in small volumes
48
Changes in Renal Function
- Rise in renal plasma flow (RPF)
- GFR increased by 50% during first trimester and remains elevated throughout pregnancy
- Changes caused by hormones, increased blood volume, posture, physical activity, nutrition intake
- Increased GFR leads to increased creatinine clearance, reduction in serum creatinine, BUN, and uric acid levels
49
Changes in F&E
- Total body water increase from 6.5 to 8.5 L
- This is because of expansion of maternal blood volume, water content in fetus, placenta and amniotic fluid, increase in intra and extracellular fluid, increase in adipose tissue
- Kidneys increase tubular re-absorption
- Additional sodium to maintain isotonic state
50
Hyperpigmentation of Skin (16 weeks)
- Caused by melanotropin
| - Darkening of nipple, axillae, vulva
51
Melasma (chloasma or mask of pregnancy)
- Hyperpigmentation (blotchy brown) over cheeks, nose, forehead
- Fades after birth but can come back with oral contraceptives or subsequent pregnancies
52
Linea Nigra
- Pigmented line extending from pubis to fundus midline
53
Striae Gravidarum
- Stretch marks during second half of pregnancy
- Could be due to genetics
- After birth they fade but dont disappear
- No topical therapy affects stretch marks
54
Angiomatas (Vascular Spiders)
- Star shaped arterioles usually found in neck, thorax, face and arms
- Results from increase blood flow due to rising estrogen
- Disappears within 3 months post-partum
55
Palmar Erythema
- Red blotches over hand due to increased estrogen
56
Pruritis Gravidarum
- Itchiness across abdomen (resolves during post partum)
57
Integumentary Changes
- Nail growth accelerated
- Hirsutism
- Increased fine course hair growth
- Hair loss slows
58
Musculoskeletal System
- Compensatory curve to maintain balance
- Weakness of upper extremities
- Symphysis widens causing pain and difficult walking
- Waddling gait
- Leg cramps from changes in calcium and phosphorus
- Restless leg syndrome is common
59
Diastasis Recti Abdominis Muscle Separation
- After birth muscles regain tone but separation of muscle can persist
60
Neurological System
- Tension headaches due to hormonal changes, eye strain, emotional tension, nasal congestion and fatigue
- Lightheadedness and syncope (fainting) are common
(Due to motor instability, postural hypotension, hypoglycemia)
- First-Trimester Fatigue
- 2nd and 3rd trimester difficulty sleeping
- Increased edema cause ocular changes (thickening of cornea and decreased intraocular pressure)
- Corneal changes can cause problems with contact lenses
- Enhanced sense of smell and sensitivity
61
Carpal Tunnel Syndrome
- Edema involving peripheral nerves
| - Paresthesia and pain in hand which radiates to elbow
62
Changes in endocrine System
- Enlarged thyroid gland
- T3 and T4 levels rise
- Basal Metabolic Rate increases
- Pituitary gland increases in size
- Prolactin levels increase
- Insulin needs increase
63
Human Chorionic Gonadotropin (HcG)
Maintains Corpus Luteum production of estrogen and progesterone until placenta takes over
64
Progesterone
- Suppresses secretion of FSH and LH
- Maintains pregnancy by relaxing smooth muscle, decreasing uterine contractility, causes fat to get deposited around the body, decreases maternal ability to use insulin
65
Prolactin
- Prepares breasts for lactation
66
Oxytocin
- Stimulates uterine contraction
| - Stimulates milk ejection from breasts after birth
67
Human Chorionic Samotomammotropin
- Growth Hormone
- Breast development
- Decreases maternal glucose metabolism
- Increases fatty acids for metabolic needs
68
Parathyroid Hormone
- Controls calcium and magnesium metabolism
69
Insulin
- Increased levels of insulin due to antagonism of placental hormones
70
Cortisol
- Increases peripheral resistance to insulin
| - Stimulates production of insulin
71
Aldosterone
- Stimulates re-absorption of sodium
72
Estrogen
- Suppresses FSH and LH
- Deposits fat around maternal body
- Promotes enlargement of genitals uterus and breasts
- Increases level of total body proteins
- Promotes retention of sodium and water
- Decreases mother ability to use insulin
73
Immune System
- Pregnancy is not a state of immunosuppression
- First and early second trimester represents proinflammatory state to allow establishment of pregnancy
- Second trimester is anti-inflammatory phase with rapid growth of fetus
- 3rd trimester is proinflammatory state with influx of immune cells in myometrium which contributes to initiation of labor, cervical ripening, membrane rupture, uterine contractions
- Changes in immune system can cause rheumatoid arthritis. When pregnancy is over there can be exacerbations of symptoms
