Maternal Physiology / Normal Pregnancy and Prenatal Care / Imaging in Obstetrics Flashcards
1
Q
Maternal Physiology
A
Pregnancy changes anatomy, physiology and biochemistry
Affects normal lab values
Affects medication dosing
2
Q
Cardiovascular System 1 ?
A
As uterus enlarges, heart rotates
Apical impulse shifts laterally
Heart size increases by 12%
Blood plasma volume increases ~50% - Varies by Size of woman Number of prior pregnancies Number of fetuses
3
Q
Cardiovascular System 2 ?
A
Cardiac output increases 40%
Stroke volume increases 25-30%
-Sensitive to maternal position
-Lateral recumbent
-Supine -they are compressing the vena cava
so lay on right or left side
4
Q
Cardiovascular System 3 ?
A
Systemic arterial pressure decreases initially (until 24-28 weeks)
Venous pressure increases in legs
-Pressure on inferior vena cava and common iliac veins
-Edema
-Varicosities
feet swelling is normal but arms not so much
5
Q
Cardiovascular System 4 ?
A
Blood flow distribution
Increased flow to uterus, kidneys, breast and skin - helps dissipate the heat
Strenuous exercise
- Diverts blood flow to large muscles
- Okay for conditioned mothers
- For nonconditioned, can decrease uteroplacental perfusion to the fetus
6
Q
Cardiovascular System 5 ?
A
90% of gravidas have systolic ejection murmurs
Increased CO
Decreased blood viscosity
7
Q
Pulmonary System 1 ?
A
Engorgement of nasopharynx, larynx, trachea and bronchi
Increased vascular markings on CXR
Diaphragm elevates 4 cm - SOB
- Reduced total lung capacity
- ribs flare out a bit more ( look below too)
Increased thoracic circumference
Decreased total lung capacity
Increased tidal volume
-Decreased reserve and residual volume
8
Q
Renal System 1 ?
A
Kidney lengths enlarge by 1-1.5 cms
Ureters elongate and widen - curve around uterus
Collecting system can contain 200 mL
- Increased risk of UTI’s
- hold more volume but increase risk of UTI
Back to normal 4 days postpartum
9
Q
Renal System 2 ?
A
Blood flow to kidneys increases by 50-85% during first half of pregnancy, lower later
Urinary flow increases two-fold in LATE pregnancy when in lateral recumbent position ( compared to supine)
Medications cleared by the kidney faster
Half of pregnant women will have glucosuria sometime during pregnancy
-NL also contributes to UTI rate
10
Q
Renal System 3 ?
A
Early in pregnancy, hormones contribute to increased urinary frequency
Bladder capacity actually enlarges
Later in pregnancy, frequency due to enlarged uterus (pressure)
11
Q
Gastrointestinal System ?
A
Stomach pushed upward
Bowel pushed back, to sides and up
Increased salivation (due to nausea?)
Gums may hypertrophy, bleed
-hormones , or even OCP
Increased GERD, esp first trimester
-more gastrin being produced and esophageal peristalsis being decreased
Increased constipation in later months
-cause slower transit time of stool
Increased risk of gallstone formation
-cause of bile stasis , GB disease
12
Q
Hematologic System 1 ?
A
Red cell mass expands by 33%, even more with iron supplementation
Greater plasma increase – anemia of pregnancy cause of dilution factor
Active transport of iron to fetus
Fetus generally not anemic, even if mother is severely anemic
13
Q
Hematologic System 2 ?
A
WBC’s 5000-12,000 in third trimester
not infection
20,000-25,000 during labor is normal
Mainly polymorphonuclear cells
- Basophils decrease slightly
- Eosinophils unchanged
Platelet production increases, but so does consumption = thrombocytopenia
-Resolves with delivery
14
Q
Skin: Hyperpigmentation ?
A
Linea nigra
Chloasma - “mask of pregnancy”
15
Q
Skin: Striae gravidarum ?
A
“stretch marks”
Abdomen, breasts, thighs, buttocks
Decreased collagen adhesiveness and it just pulls apart
Genetic predisposition
No effective treatment
16
Q
Skin continued ?
A
Spider angiomas
Palmar erythema- cause more heat through the hands trying to be released
Cutis marmorata - vasomotor instability
Hemorrhoids
Brittle nails with grooves (Beau’s lines)
-trauma to the body and the blood etc go else were causing this
Thickened hair (ends 1-5 months postpartum and shedding begins
17
Q
Metabolism: Increased nutritional requirements ?
A
Rest more
Increased appetite (for some)
Pica (rare) - dirt
18
Q
Metabolism: Weight gain ?
A
Uterus and contents ( fetus)
Breast enlargement
Blood and water volume 6.8L
Average weight gain is 27.5 lbs
19
Q
Placenta ?
A
Purpose is physiologic exchange between fetal organs and maternal tissue
Oxygen and nutrients to fetus
CO2, urea, catabolites back to the mother
20
Q
Placenta: Cotyledons ?
A
Cotyledons – 12-15 subunits of the placenta - tents of blood where the blood collects and during contraction they collapse
At height of contraction, cotyledons are mainly devoid of blood flow. In uterine tetany, fetal hypoxia develops
21
Q
Placenta and Placental-Fetal Unit: Produces increasing amounts of steroids in late ?
A
first trimester
22
Q
Placenta and Placental-Fetal Unit: Fetal adrenal cortex _______ than adult
A
larger
helps with fetal development and growth , maturation and delivery
23
Q
Placental Secretions ?
A
Human chorionic gonadotropin- hCG
Properties similar to LH from pituitary
Alpha subunit common to all glycoproteins
Beta subunit is specific to the hormone
24
Q
HcG secretions: Measurement of β-hCG detects pregnancy______ after fertilization ( qualitative)
A
6-12 days
25
HcG secretions: Levels peak at ______ gestation
60-90 days
then we look for quantitative and if it is still increasing and increasing then it could be ectopic
26
Placental Transport of Drugs: Few substances that won’t cross the “placental barrier” ?
Heparin
Insulin
these wont cross cause Too large of molecules
27
Umbilical Cord: Connective tissue of cord is called ?
Wharton’s jelly
28
Umbilical Cord: ___arteries, ___ vein twisted around each other
Two
one
29
Umbilical Cord: _______ carry blood from fetus to the mother
Arteries
30
Umbilical Cord: ____ returns blood to the fetus
Vein
31
Umbilical Cord: Average diameter ?
12 mm
32
Umbilical Cord: Average length ?
50-60 cms
33
Umbilical Cord: Nuchal loops around baby’s neck 25% of _________________ deliveries
spontaneous vertex
34
Umbilical Cord: Short cord related to _______________ maybe a shorter umbilical cord
oligohydramnios
| not enough amniotic fluid
35
Umbilical Cord: True knots in __ of deliveries – can lead to fetal demise
1%
36
Umbilical Cord: At delivery, a portion of the cord should be kept for ?
cord blood gas sampling
more accurate then a APGAR score and it is preserved for several hours
37
Normal Pregnancy and Prenatal Care definition ?
Pregnancy defined as the physiologic process of a developing fetus within the maternal body
38
Gestational age is the amount of time since first day of ____
LNMP
(precedes fertilization by 2 weeks)
Assume a 28 day cycle
39
Gestational age expressed in ?
Expressed in completed weeks
40
__ weeks to term pregnancy
40
41
_________________ age is the age of the conception, calculated from time of implantation
Developmental/fetal
42
Naegele’s Rule calculates ?
estimated due date (EDD)
43
Naegele’s Rule ?
Add 7 days to first day of LNMP
Subtract 3 months
Add 1 year
Ex: First day of LNMP 5/1/15
44
Gestation: Divided into __ trimesters, each __ calendar months
3
3
45
Gestation: First trimester has two parts ?
Embryonic period
Fetal period
46
Embryonic period: ____weeks gestational age
2-10
47
Embryonic period: Most sensitive to ?
teratogens
* *sometimes people dont know they preggo yet and still drink alcohol etc .
* *
48
Fetal period: __ weeks after FDLNMP
10
| 8 weeks after fertilization
49
Nulliparous - ?
never pregnant
50
Primiparous - ?
first pregnancy
51
Multiparous - ?
delivered more than one child
52
Gravid = ?
pregnant
53
Gravida = ?
total number of pregnancies, regardless of outcome
delivered pregnancy or not
54
Parity= ?
number of births
55
Parity includes what type of births ?
full term
preterm
abortions
living children
56
Preterm births: Weighing ____ or more, at OR beyond __ completed weeks, alive or dead
500 g
20
57
Abortions: Ending before __ weeks, induced or spontaneous
20
58
Twins = ___ gravid event, but ___ parity
one
two
59
Ex: G2 P3 Ab 0 ?
(had twins once)
60
Ex: G2 T1 P0 A0 L1 ?
(currently pregant)
61
Live birth – ?
evidence of life
62
Infant: Live-born human, from moment of birth until ?
1 year of age
63
Preterm infant: Born at _____ completed weeks gestation
20 -37
64
Term infant: Born between ______ and ______ weeks
37 0/7 and 42 0/7
65
Postterm infant: Born after __ weeks
42
66
Large for gestational age (LGA) – aka ?
macrosomia - “big body”
Beyond 90th percentile
67
LGA baby are prone to ?
gestational DM are prone to this
cephalopelvic disproportion
68
Low-birth-weight infant – ?
2500 g or less
69
Abortion – based on age or weight: Expulsion of ____________________ with or without fetus
complete or partial placenta
70
Abortion – based on age or weight: Expulsion of fetus, alive or dead weighing less than _____ or less than __ completed weeks
500 g
20
71
Embryo –until __ weeks gestation
10
72
Fetus – ___ weeks
10+
73
Neonatal period ?
Birth to 28 days of life
Infant is a newborn, a neonate
74
Perinatal period: __ weeks gestation to 7 days of life
28
before and after birth
75
Pregnancy Symptoms and Signs: Nausea/vomiting
| ?
50% of pregnancies
2 weeks until 13-16 weeks
Small, frequent meals, emotional support
Extreme – Hyperemesis gravidarum
76
Pregnancy Symptoms and Signs: Mastodynia ?
Tingling to pain
Caused by hormones
77
Pregnancy Symptoms and Signs: Breast engorgement ?
Fullness, esp in primips ( first pregnancies)
Montgomery’s tubercles
Periareolar veins ( venous engorgement )
78
Pregnancy Symptoms and Signs: Colostrum secretion ?
As early as 16 weeks
variation of normal
79
Pregnancy Symptoms and Signs: Fetal Movement ?
Perception of fetal movement – “quickening”
18-20 weeks in primips
14 weeks in multips ( recognize it earlier)
Not a reliable symptom
80
Pregnancy Symptoms and Signs: Elevated basal body temperature ?
Progesterone causes a 0.5ᵒ F increase
81
Pregnancy Symptoms and Signs: skin changes ?
Chloasma
Linea nigra
Striae
Spinder telangiectasia
82
Chloasma ?
Darkening of forehead, bridge of nose, cheeks
Exacerbated by sunlight
83
Linea nigra ?
Midline from umbilicus to pubis
Lightens somewhat after delivery
84
Spider telangiectasia ?
Vascular stellate lesions
cheek or chest
85
PUPPP aka ?
Pruritic Urticarial Papules and Plaques of Pregnancy
86
Most common specific dermatosis of preg ?
PUPP
87
Most common in primip and multiple gestation ?
PUPP
88
PUPP description ?
Erythematous papule within striae
* *itchy hive like lumpy within the straie and erythematous and late in the third trimester
* *
89
When does PUPP start ?
Usually starts late 3rd trimester
90
Where does PUPP start ?
Starts on abdomen, spreads to extrem
91
PUPP tx ?
Treat symptoms (pruritus) –low potency steroid cream
** use low potency steroid for the itch**
92
Pregnancy Symptoms and Signs: pelvic organ changes ?
Chadwick’s sign
Hegar’s sign
Leukorrhea
Pelvic ligaments
Abdominal enlargement
Uterine contractions
93
What is the Chadwick’s sign
| ?
Bluish discoloration of cervix and vagina
cause venous engorgement / congestion
94
What is the Hegar’s sign
| ?
Widening and softening of body of uterus
Cervical softening and widening of os
Occurs at 6-8 weeks gestation ( early)
95
What is the Leukorrhea ?
Vaginal discharge ( white , NL , just increased in amount)
96
Pelvic Organ Changes: Pelvic ligaments ?
Relaxation of sacroiliac and pubic symphysis
97
Pelvic Organ Changes: Abdominal enlargement ?
Good correlation between fundal measurement and gestational age ( checks fetal growth )
98
Pelvic Organ Changes: Uterine contractions ?
Braxton-Hick’s – painless, tightening, pressure
Usually begin at 28 weeks
Often stop with walking, exercise
- while true babe they get worse with exercise
- not true labor, its like the uterus is getting ready
99
Diagnosis: Fetal heart tones FHT’s ?
Handheld Doppler after10 weeks
Fetoscope after 18-20 weeks
100
Diagnosis: Uterine size/Fetal palpation ?
Uterine enlargement or fetal parts/position
101
Diagnosis: Imaging studies ?
Sonography
102
Handheld Doppler after __weeks
10
103
Fetoscope after_____ weeks
18-20
104
Sonography ?
Crown-rump length (CR)
top of the head to the butt and very accurate at determine gestational age
105
Diagnosis: Home pregnancy tests - qualitative ?
First voided morning urine sample
hCG (beta)
106
Diagnosis: Urine pregnancy tests ?
In office, to confirm
Reliable, rapid, inexpensive
107
Diagnosis: Serum pregnancy tests - quantitative ?
β-hCG – 6-12 days after conception
Used more for evaluating threatened abortion, ectopic and molar pregnancies
see if it is increasing or decreasing
108
Uterine size: 8 weeks – ?
fundus at pubic symphysis
109
Uterine size: 16 weeks – ?
midway between pubic symphysis and umbilicus
110
Uterine size: 20 -22 weeks – ?
at umbilicus
111
Uterine size: 18 weeks and up – ?
measure in cms from pubic symphysis to top of fundus
112
Uterine size: After 36 weeks, ?
height may decrease as head descends into pelvis
** the baby drops and head goes into the pelvis **
113
______ of pregnancies have complications
5-20%
114
Prenatal care focuses on prevention and identification of ?
risk factors
115
Evidence-based that prenatal care helps ? And IDs ?
Helps decrease complications
Identifies high-risk pregnancies for special care
116
Prenatal Care: Ideally an evaluation occurs before conception ?
Identify risk factors
Discuss smoking, alcohol, teratogens
Discuss nutrition, exercise, vitamins
Start folic acid 3 months before conception
117
Start folic acid __ months before conception
3
118
Prenatal Hx: Obstetric history ?
Current symptoms
Outcomes of previous pregnancies
119
Prenatal Hx: Medical history ?
Preexisting conditions such as :
diabetes, thyroid dz, HTN, epilepsy
Hx of blood transfusion
120
Prenatal Hx: Surgical history ?
Previous abdominal, gynecologic procedures
Recurrent fetal losses
-cause cervical incompietnce, maybe it dilates to early
Previous Caesarean section
- doesn't always mean they will need another, VBACS
- vaginal birth after c section
** ( cause we want to know about scar tissue) **
121
Prenatal Hx: Family history ?
Diabetes, twinning, familial disorders
122
Prenatal Hx: Social history ?
Tobacco, alcohol, contact with IVDU or other drug use
Exposures – workplace, home
123
Prenatal Physical Exam: Complete PE at _____ visit ?
first
124
Prenatal Physical Exam: Pelvic exam ?
Bony pelvis
Fundal height
Cervical length
Cervical os
125
Pelvic exam: Bony pelvis ?
pelvimetry to assess for cephalopelvic disproportion (CPD).
inside of the pelvic rim measurements
Usually allow a trial of labor, though
126
Pelvic exam: Cervical length?
3-4 cms average
127
Pelvic exam: Cervical os?
nullip will be closed
multip may be partially open
128
Prenatal Blood Tests on First visit ?
CBC - anemia
Blood group, Rh typing
Screen for antibodies against blood group antigens
VDRL/RPR
Hep B surface antigen
Antibodies to rubella and
HIV
Glucose challenge test (if hx of gest diabetes or risk factors for diabetes)
129
Prenatal Blood Tests: Genetic screening - _________________ and maternal serum to screen for trisomy (21, 18 and 13)
Fetal nuchal translucency
130
Prenatal Blood Tests: Genetic screening - Serum alpha fetoprotein (AFP) at _____ weeks to screen for open neural tube defects
15-18
131
Prenatal Blood Tests: Genetic screening - Hemoglobin electrophoresis for ?
sickle cell, CF
132
Prenatal Blood Tests: Genetic screening - Maternal serum testing – ?
whole panel!
more accurate
material serum is more comprehensive and less scary
133
Prenatal Blood Tests: Invasive genetic testing -
Must be offered to all women, esp +35 or abnormal family hx or risk factors
Chorionic villus sampling at 9-13 weeks
Amniocentesis at 15-20 weeks
Complication rates are very low and detection for aneuploidy is +99%
134
Chorionic villus sampling at_____ weeks
9-13
135
Amniocentesis at ____ weeks
15-20
136
Prenatal Tests: Urine testing ?
U/A with C&S
At EVERY visit – UA for
137
Urine testing: Protein- ?
to assess kidneys
138
Urine testing: Glucose ?
– though not usually significant unless gestational diabetes is present
139
Urine testing: Ketones ?
– inadequate carb intake
140
Prenatal Tests: Pap – at initial visit unless ?
normal exam in the past year
141
Prenatal Tests: _________ – for high-risk patients ?
Tuberculin skin test
142
Prenatal Tests: STDs ?
```
Syphilis
Chlamydia
Gonorrhea
Herpes simplex virus - prophylaxis like acyclovir to keep it at bay if they delivery by vag.
HIV
check prenatally to avoid transmission
```
143
Prenatal Tests: Other infections ?
Trichomonas
Candidiasis – often asymptomatic
Bacterial vaginosis – can cause preterm labor, PROM, chorioamnionitis
G can cause eye injuries , premature labor ,
144
Prenatal Visits: Standard schedule ?
Every 4 weeks from 0-28 weeks
Every 2 weeks from 28-36 weeks
Weekly after 36 weeks
145
Prenatal Visits: Increased frequency depends on risk factors ?
Maternal conditions, age
Fetal complications
146
Prenatal Visits: each visit ?
```
Maternal weight gain
Blood pressure
Fundal height
Fetal heart tones
Edema
Fetal size and position
UA
```
147
Maternal Weight Gain: Note ?
prepregnancy weight
148
Maternal Weight Gain: Woman who is 15% or more below ideal body weight or of short stature is at risk for ?
small for gestational age (SGA) baby
149
Maternal Weight Gain: ____________ – may have inadequate diet
Adolescents
150
Maternal Weight Gain: ACOG recommends weight gain of ?
25-35 lbs
151
Maternal Weight Gain: Obese women should gain ?
less (15-25 lbs) or risk of macrosomia (LGA)
152
Maternal Weight Gain: Underweight women should gain more ?
(28-40 lbs)
153
Blood Pressure should be taken while ?
sitting
154
BP decreases _____ mm in 2nd trimester
5-7
155
BP should go back to NL in ___ trimester
3rd
156
BP Elevation may precede __________ ?
proteinuria
157
Fundal Height Measured at each visit after ?
20 weeks
158
Fundal Height: If measurement does meet expected amount by more than 2 (cms or weeks) then further evaluation of _______________________ is needed
fetal size and amount of amniotic fluid via US
159
Fetal Heart Tones ?
Doppler
Fetoscope
Rate, rhythm
-110-160, higher rate earlier in pregnancy
Accelerations, decelerations of rate
160
Edema: Note any _________ episodes of generalized edema
transient
161
Edema: Leg edema in late pregnancy is ________
natural
162
Edema: Edema of upper body – face and hands, esp with ↑ BP may be first sign of ?
preeclampsia
163
Fetal Size and Position: After 26 weeks – ?
Leopold’s maneuvers
164
Fetal Size and Position: Persistence of abnormal lie into late pregnancy suggests abnormality ?
If abnormal lie persists, consider ?
Abnormal placenta
Uterine anomaly
Need US
external version after 37 weeks
painful
165
Third Trimester Evaluations: 1-hour glucose challenge test with a 50 g glucose load at _________ (all patients)
24-28 weeks
check 1 hr glucose
and CBC
166
Third Trimester Evaluations: Group B streptococcus ?
Universal vaginal and rectal cultures at 35-37 weeks
if pos. give them PCN at labor
and CBC
167
Group B Streptococcus: Antibiotics to mothers who ?
Have positive cultures
Delivered a prior neonate with group B strep infxn
Had group B strep bacteruria during current pregnancy
Have known risk factors for PROM, prematurity
Women with group B strep who are scheduled for C section before rupture of membranes do not need antibiotics
168
Group B Streptococcus: __ of neonates exposed to group B strep develop symptoms
2%
so Treat mothers with antibiotics before labor
169
Neonate sxs GBS ?
Group B Streptococcus
170
GBS drug of choice ?
Pen G
Cefazolin if penicillin allergy and no hx of anaphylaxis with penicillin
171
Other Issues of Prenatal Care ?
Bathing and swimming are permitted
Douching should be avoided
Smoking ↑ risk of IUGR, placenta previa, placenta abruption, preterm birth
Alcohol can cause FAS even with 2 oz/day
fetal alcohol syndrome
Exercise encouraged, esp yoga
172
Immunization to pregnant women ?
killed, toxoid or recombinant vaccines okay. Encourage flu shot. NO live vaccines
**no live vaccinate like MMR, varicella **
173
Intercourse in pregnant women ?
okay unless pain or bleeding occurs
174
______ is permitted (auto, train, plane) in pregnant women
Travel
175
Prenatal Care: Nutrition ?
balanced diet, prenatal vitamins
176
Nutrition: 127 lbs prepregnant = ?
2300 kcal/day
177
Nutrition: Additional ___ kcal during pregnancy
300
178
Nutrition: Additional ___ kcal during breastfeeding
500
179
Imaging in Obstetrics: Safe
| Widely available ?
Primary modality is 2-D US
180
Imaging in Obstetrics: Good for certain circumstances
| Too costly for routine use ?
3D/4D US and MRI available
* *good if you expect abnormality like cleft palate
* *
181
Imaging in Obstetrics: Limited use because of safety issues
| May be necessary in some maternal conditions ?
CT
182
Ultrasound Imaging options ?
Transabdominal or transvaginal probe
Choice depends on what is being evaluated
183
US: cervix or early gestation choice ?
transvaginal
184
US: fetus in 3rd trimester choice ?
trans abdominal
185
First Trimester US Indications ?
Confirm intrauterine pregnancy
-and location so it is good for ectopics
Assess pelvic pain and bleeding
Estimate gestational age
Confirm viability ( HR)
Determine number of gestations
Genetic screening
Evaluate basic anatomy
Nuchal translucency - downs syndrome
Assess uterine and adnexal anomalies
186
Second and Third Trimester US screens for ?
Fetal anomalies
Fetal growth – BPD, HC, AC,
femoral length
Fetal well-being (next slide)
Fetal lie and presentation
Placental anomalies
Cervical insufficiency
Gestational age
Number of gestations
Viability
**bi-parietal diameter for hypocephalus etc.
Head circumference and abdominal circumference **
187
Fetal Well-Being: BPP ?
Biophysical profile (BPP)
4 US parameters and a nonstress test
Scored 0-10/10
188
Fetal Well-Being: Fetal Doppler exam ?
Measure of speed that blood is moving in a vessel (artery or vein)
189
US for Cervical Evaluation ?
Shape and length
Most helpful earlier in gestation
Can help determine risk for preterm labor
Determine need for progesterone or cerclage
190
Non-stress test ?
two or more fetal HR accelerations peak at least 15 beats per minute above the baseline and last 15 seconds from baseline to baseline w/in 20 minute period w/ or w/o fetal movement discernible by the woman
191
Amniotic fluid volume ?
A single 2 cm x 2 cm pocket is considered adequate of AFI greater than 5 cm
192
Fetal breathing movements ?
One or more episodes of rhythmic fetal breathing movements of 30 seconds or more w/in 30 minutes
193
Fetal movements ?
At least 3 discrete body or limb movements.
Episodes of continuous movement are considered as a single movement
194
Fetal tone ?
One or more episodes of extension of a fetal extremity or trunk with return to flexion, or opening or closing of a hand
