Obstetrics Flashcards
(225 cards)
1
Q
oligomenorrhea
A
cycle length >35 days -
meaning don’t have period every month
2
Q
Polymenorrhea
A
cycle length <21 days
meaning > 1 period every month
3
Q
Hypomenorrhea
A
Scanty menstruation - light flow
4
Q
Menorrhagia
A
Regular cycles
Excessive flow or duration
5
Q
Amenorrhea
A
Absence of menses for 6 months
6
Q
Metorrhagia
A
Uterine bleeding at irregular intervals, particularly between the expected menstrual periods
7
Q
Menometorrhagia
A
Irregular cycles
Excessive flow or duration
8
Q
Gestational Age
A
Age in days or weeks from the last menstrual period
9
Q
First trimester
A
up to 14 weeks GA
10
Q
Second trimester
A
14-28 weeks GA
11
Q
Third trimester
A
28 weeks until delivery
12
Q
Preterm definition
A
24-36 weeks
13
Q
Term definition
A
37-42 weeks
14
Q
Post-term
A
Past 42 weeks
15
Q
Gravidity
A
Number of times a woman has been pregnant
16
Q
Parity
A
Number of pregnancies that led to birth after 20wks or > 500g infant
17
Q
G1P1001 = ?
A
1 baby delivered at term
P - - - - Term Preterm Abortions Living children
18
Q
G2P1011 = ?
A
Pregnant two times
One living child delivered at term
One abortion
19
Q
How does maternal cardiac physiology (CO, SV, pulse, PVR, BP) change when pregnant?
A
Increased blood volume = CO increases by 30-50% SV increases 10-15% Pulse increases 15-20 BPM SEM and S3 gallop common
PVR falls
Fall in BP 2nd semester, return to normal during 3rd trimester
20
Q
How does maternal respiratory physiology (RR, vital capacity, inspiratory reserve volume, residual volume, TLC, inspiratory capacity, tidal volume) change when pregnant?
A
UNGHANGED: RR, vital capacity, inspiratory reserve volume
Decreased: Functional reserve capacity, expiratory reserve volume, residual volume, TLC (b/c uterus is getting big)
Increased: Inspiratory capacity, tidal volume
21
Q
How does maternal renal physiology (GFR, Cr, kidney size, bladder) change during pregnancy?
A
Bladder becomes intra-abdominal organ
GFR increases 50%
CrCl increases by 150/200 cc/min
BUN & serum Cr goes down by 25%
Marked increase in renin & angiotensin levels but reduced vascular sensitivity to their HTN-effects
Inc tubular re-ab of Na+ = one of reasons why preggers ppl have edema
Increased glucose excretion
22
Q
What is done at almost every prenatal visit?
A
H&P
Fetal exam (fetal heart tones, fundal height, fetal presentation (>36 wks)
Urine dip (protein, glucose, leukocytes)
23
Q
When is maternal cystic fibrosis screening done during pregnancy?
A
First visit (blood test mom)
24
Q
When is group B strep culture done during pregnancy
A
36 weeks
Also test for STDs at this time - need to know before delivery - including HIV
25
What labs are drawn during the first prenatal visit?
```
Labs:
Hct/hgb
Rh factor
Blood type
Antibody screen
Pap smear
Gonorrhea/chlamydia cx
UA (protein, glucose, ketones)
Urine culture (treat)
Cystic fibrosis screen
Infection screen (rubella, syphilis, hep B, HIV, Tb)
```
26
History questions to ask - obstetrical & menstrual
H&P:
Biographical (age, race, occupation, marital status)
Obstetrical (GP, deliveries (vaginal, cesarian), complications, infant status, birth weight
Menstrual (LMP, menstrual irregularities)
27
Pertinent medical history to ask for at prenatal visit
```
Asthma
Diabetes
Hypertension
Thyroid disease
Cardiac disease
Seizures
Rubella
Previous surgeries
STDs
Allergies
Medications
Smoking
Alcohol
Drugs
```
28
Family history to ask for in prenatal visit
```
Multiple gestations
Diabetes
HTN
Bleeding disorders
Hereditary disorders
Mental retardation
Anesthetic problems
```
29
When do you give anti-Rho D immunoglobulin if indicated?
28 weeks
Within 72 hours of bleeding
30
Physical exam components prenatal obstetrics visit
```
Vitals
Head & neck
Heart & lungs
Back
Pelvic:
External genitalia - lesions, bartholins gland
Vagina - discharge, inflammation
Cervix - polyps, growth
Uterus - masses, irregularities, size vs GA
Adnexa - massed
```
31
Questions to ask at every prenatal visit (after first)
```
Presence of fetal movement
Vaginal bleeding
Leakage of fluid
Contractions/abdominal pain
Pre-eclampsia sx: HA, visual changes, RUQ pain)
```
32
Subsequent prenatal visits 4 MUST do physical exam
BP
Urine dip
Fundal height
Fetal heart rate
33
What is the cfDNA test, what does it screen for and when in pregnancy is it done?
Cell-free fetal DNA - sample of maternal blood (non-invasive) - next generation sequencing looking for below diseases
Done at > 10 weeks
```
Tests for:
Down syndrome T21 (99% detection)
Trisomy 13
Trisomy 18
Turner syndrome
Sex chromosome aneuploidies
```
34
Quad screen - what is it, when is it done?
Done 16-18 wks - test of maternal serum
```
Labs drawn:
Unconjugated estriol
B-hcg
Alpha-fetoprotein
Inhibin A
```
Screening for:
Trisomy 18, 21, neural tube defects
35
First trimester screen - when is it done, why, what does it test for?
Invasive or noninvasive
Labs values drawn
Done at 11-13 weeks
Optional, non-invasive
Combines maternal blood screening tests (B-hcg - increased, PAPP-A- decreased)
with a findings on a fetal US evaluation to identify risk for Down syndrome (T21)
(can also find Edward syndrome (trisomy 18))
36
Fetal ultrasound findings on the FTS suggestive of Down syndrome
Increased nuchal translucency
37
Quad screen findings associated with Down syndrome
UE3 decreased
AFP decreased
B-Hcg increased
Inhibin A increased
38
Quad screen findings associated with Edwards syndrome
All decreased
UE3, AFP, B-Hcg, inhibin A
39
Quad screen findings associated with NTD
Normal uE3
Increased AFP
B-Hcg normal
Inhibin A
40
When is gestational diabetes tested for and how?
24-28 weeks
| 1-hour 50g glucose tolerance test
41
Fundal height - where is the height of the uterus at 12 weeks?
Pubic symphysis
42
Fundal height - where is the height of the uterus at 16 weeks?
Between pubic symphysis and umbilicus
43
Fundal height - where is the height of the uterus at 20 weeks?
At the level of the umbilicus
44
Fundal height - where is the height of the uterus at 20-36 weeks?
Uterine height correlates with gestational age after 20 weeks
Fundal height in cm should correlate with gestational age +/-3
If it doesn’t match - consider inaccurate dating (most common), multiple gestations, or molar pregnancy
Post 36 weeks, fundal height may not correlate with GA because fetus has started to descend into the pelvis
45
What are the different forms of fetal surveillance & when are they performed?
```
Fetal movement counts
Non-stress tests
Contraction stress tests
Biophysical profile & modified
Doppler ultrasonography
```
Performed in T3 unless needed earlier
Choice and frequency of testing depends on indication, GA, medical condition, & experience of the practitioner
46
Non-stress test - what it is and the 4 components
The NST evaluates 4 components of fetal heart rate tracing:
1. Fetal HR (110-160)
2. Variability
3. Periodic changes - accel
4. Periodic changes - decel
47
Greatest RF for ectopic pregnancy
Prior ectopic pregnancy
48
RF for ectopic pregnancy
Prior ectopic (greatest)
PID
Tubal surgery
IUD
49
Definitive dx for ectopic
Pelvic Ultrasound
50
Ectopic pregnancy clinical presentation, PE, dx, tx
Patient with a history of prior ectopic, PID, tubal surgery, IUD
CP: Complaining of vaginal bleeding, abdominal pain,amenorrhea
PE will show adnexal tenderness or unexplained hypotension
Labs will show positive pregnancy test and lower than expected serum beta-hCG levels
Diagnosis is made by ultrasound
Most commonly located in a fallopian tube
Treatment is methotrexate or surgery
51
Most common location ectopic
Fallopian tube
52
RF for developing rectocele
risk factors for development of a rectocele include obesity, vaginal childbirth, pelvic surgery, collagen disorders and advanced age.
53
Most effective non surgical tx of rectocele
Pessary
Can also tx constipation if present
54
Most common surgical management of rectocele is...
a posterior colporrhaphy which has an anatomic cure rate of up to 96%.
55
```
Which of the following drugs is C/I in pregnancy?
Labetalol
Methyldopa
Adenosine
Catopril
```
Angiotensin-converting-enzyme (ACE) inhibitors (e.g. captopril) are category D drugs and are contraindicated in pregnancy. The most serious fetal effects occur when they are taken in the second and third trimester and include oligohydramnios, renal agenesis, fetal skull abnormalities, and increased risk of stillbirth.
56
Which class of antibiotics is a/w fetal kernicterus if taken in third trimester?
Sulfonamides
57
Bacterial vaginosis
Patient will be complaining of malodorous vaginal discharge
PE will show thin, gray/white discharge
Labs will show pH > 4.5, clue cells
Diagnosis is made by KOH to smear → fishy odor, "whiff test", Amsel Criteria
Most commonly caused by Gardnerella vaginalis
Treatment is metronidazole
58
Endometriosis pathophysiology
CAUSE = RETROGRADE MENSTRUATION
Endometriosis is a benign, estrogen-dependent condition that results in endometrial tissue developing in extrauterine sites.
The most common site for endometrial implantation is the pelvis, with the ovaries, posterior cul-de-sac, and anterior cul-de-sac affected most frequently.
Endometriosis is a disease of women of reproductive age and is rare in postmenopausal women unless they are on estrogen replacement therap
59
Primary amenorrhea
Failure of menses to occur by age 15 despite normal growth of secondary sexual characteristics
Failure of menses to occur by age 13 in the absence of secondary sexual characteristics
60
Secondary amenorrhea
Cessation of menses anytime after menarche has already occurred
(Three + months for women who have regular menses. Six + months for those with irregular menses)
Lab workup: FSH, LH, prolactin, TFTs, testosterone, hCG
Comments: Pregnancy is the most common cause of secondary amenorrhea
61
Three "D's" of EnDometriosis
Dysmenorrhea (painful period)
Dyspareunia (painful sex)
Dyschezia (painful bowel movement)
62
PE Endometriosis
Often normal, can have localized tenderness or pelvic pain
63
Diagnosis Endometriosis
Definitive diagnosis is laparoscopy
Initial workup is pelvic ultrasound - often times non-diagnostic for endometriosis but rules out other causes of pelvic pain
64
Management of endometriosis
Pain management (NSAIDs), Cessation of menstrual cycle with OCP, Gynecology referral
Surgical management with laparoscopic removal of implants is option - especially for those patients wishing to get pregnant
65
Ddx endometriosis
Mittelsmerz
PID - has BILATERAL adnexal pain, FEVER, CMT, DISCHARGE
Ruptured ovarian cyst - Acute onset unilateral pelvic pain with NAUSEA, VOMITING
66
What is the most common location of endometrial tissue in endometriosis?
Ovaries
67
Amenorrhea labs
FSH, LH, prolactin, TFTs, Testosterone, hCG
68
What is the most common cause of secondary amenorrhea?
Pregnancy
69
Definition of secondary amenorrhea
Cessation of menses anytime after menarche has already occurred
Absence of regular menses for THREE months (women with regular menses) or absence for SIX months in women with irregular menses
70
Definition of primary amenorrhea
Failure of menses to occur by age 15 despite normal growth of secondary sex characteristics
OR
Failure of menses to occur by age 13 in absence of secondary sexual characteristics
71
Chronic HTN definition
High BP outside pregnancy
High BP prior to 20 wks gestation
High BP existing 12 weeks PP
72
Preeclampsia definition
New onset HTN (>140/90, measured twice >4 hours apart) after 20 wks AND...
Proteinuria (1+ dipstick, >300 24hr, or protein/Cr ratio > 0.3) OR...
Thrombocytopenia (plt <100,000), Cr >1.1, LFTs 2x ULN, pulmonary edema, cerebral or visual symptoms
73
Symptoms of preeclampsia
Usually ASYMPTOMATIC - must catch on routine screening
74
What % of pt with chronic HTN develop preeclampsia in pregnancy and how is it defined?
25%
For women with prior chronic HTN with previous proteinuria, preeclampsia is defined as worsening HTN or development of more severe features (RUQ/epi pain = hepatic ischemia, Cr >1.1 or doubling of Cr, pulm edema, plt < 100,000)
75
Pathophysiology of preeclampsia
Vasospasm in various organs (brain, kidneys, lungs, uterus) - cause of vasospasm unknown - how placental vasculature dev early on in pregnancy contributes
76
Tx preeclampsia
Definitive - delivery
Preterm - close monitoring - NST and biophysical profiles - dec activity
Term - deliver fetus - vaginal via IOL
MgSo4 for seizure PPX if delivering the fetus - monitor for toxicity (Mg levels, check reflexes)
77
HEELP Syndrome def
Severe preeclampsia with:
Hemolysis
Elevated liver enzymes
Low platelets
A/w high morbidity - deliver IMMEDIATELY - May occur with or without HTN
78
RF for HTN diseases in pregnancy
```
Nulliparity
Age > 40
Fam Hx preeclampsia
Chronic HTN,
Chronic renal dz
DM
Multiple gestations
Hx preeclampsia
```
79
Anti HTN drugs safe in pregnancy
Short term - IV labetalol, IV hydralazine
Long term - PO labetalol, methyldopa, nifedipine
80
Are ACEI safe in pregnancy?
NO - CONTRAINDICATED- TERATOGENIC
81
Are diuretics a safe choice of anti- hypertensive?
Not used in pregnancy bc dec plasma volume which may be detrimental to fetal growth - same w/Na restriction
82
What does gestational DM result from?
Results from human placental lactogen secreted during pregnancy, which has glucagon-like effects
83
How is DM screened for and at how many weeks?
1 hour GTT —> results > 140 then follow up with 3 hour GTT
Fasting > 95
1 hour > 180
2 hour > 155
3 hour > 140
= gestational DM
84
Maternal effects of GDM
```
4x risk preeclampsia
Inc risk bacterial infections
Higher rate cesarean delivery
Inc risk polyhydramnios
Inc risk birth injury
Inc lifetime risk of T2DM
```
85
Fetal effects of DM
Inc risk perinatal death
Macrosomia —> birth injury (shoulder dystocia)
Metabolic derangements —> hypoglycemia, hypocalcemia
86
What to do differently with moms who have A2 (requires insulin/oral agents) GDM at their OB appointments
Have them do glucose control log - check at every prenatal visit
Maintain fasting glucose < 95, and 2 hr post-prandial < 135
If A1 with continued increase in glucose - start PO agent (metformin, glyburide)
If A2 with continued increase in glucose - switch to insulin
Fasting glucose is most important for fetal and maternal effects
At 32-34 weeks - fetal testing (biophysical profile or twice weekly NST with amniotic fluid index), US for growth
87
What extra testing to moms with A1 (diet-controlled) GDM need during pregnancy?
Have them do glucose control log - check at every prenatal visit
Maintain fasting glucose < 95, and 2 hr post-prandial < 135
US for growth at 36-39 weeks
88
How is delivery approached differently for moms with A2 GDM?
Well-controlled: Delivery at 39 weeks to dec risk of still birth
Poorly controlled - deliver as clinically indicated before 39 weeks
Maintain euglycemia during labor (insulin drip for A2)
May offer cesarean delivery (to avoid birth trauma or shoulder dystocia) if fetal weight >4500 g
89
Risk Factors for shoulder dystocia
Maternal: Obesity, multiparity, GDM, AMA (>35YO)
Fetal: Post-term (>42 wk), macrosomia, male
Intrapartum: Prolonged 1st/2nd stage labor, history of shoulder dystocia
90
Shoulder dystocia management
```
HELPERR acronym of maneuvers
Call for Help
Episiotomy
Legs up (McRoberts maneuver)
Pressure suprapubically
Enter vagina for shoulder rotation (Woods screw/rubin_
Reach for posterior arm
Return head to vagina for cesarean (Zavanelli maneuver)
```
91
Why is shoulder dystocia an obstetric emergency?
Because if infant is not delivered quickly, it may suffer neurologic injury/death from hypoxia
92
What is the turtle sign?
In shoulder dystocia the turtle sign is when the fetal head emerges and then retracts against the perineum like a turtle head bobbing out then in
93
Complications of shoulder dystocia?
Brachial plexus nerv injuries
Fetal humeral/clavicular fracture
Hypoxia
Death
94
Definition of hyperemesis gravidarum
Severe vomiting during pregnancy that results in weight loss, dehydration, and metabolic derangements
95
Workup of hyperemesis gravidarum?
It is kind of diagnosis of exclusion - you must rule out other causes of vomiting first - molar pregnancy, thyrotoxicosis, GI etiology
96
Treatment hyperemesis gravidarum
Vitamin B6 (pyridoxine) with doxylamine (name brand: Unasom - anti-histamine w/ anti-nausea effects, safe in pregnancy)
IV hydration, thiamine & electrolyte replacement, acid-reducing medications (PPI), antiemetics
97
Antiemetics safe in pregnancy
Non-pharmacological changes FIRST - avoid triggers, change diet etc...if not resolved move on to pharmacological options:
First try vitamin B6 (pyridoxine) & doxylamine (Unasom) - if doesn't work, d/c and try:
Other anti-histamines: Diphenhydramine, meclizine, dimenhydrinate (dramamine)
Not resolved, ADD: Metoclopramide (reglan), promethazine (phenergan), prochlorperazine
Not resolved, add odansteron (Zofran)
98
29-year-old G2P1001 at 16 weeks pregnant presents for prenatal care - blood type is A-negative and she has a positive antibody screen - what is the next best step in management?
Identify the antibody type - some are dangerous for fetus and some are benign - remember: "Kell kills, Duffy Dies, Lewis Lives" i.e....
Anti-Lewis antibodes = benign
Anti-Kell antibodies = fatal
Anti-D antibodies = fatal
Anti-Duffy antibodies = fatal
They are fatal because they cause hemolytic disease of the newborn when the mother's immune system attacks the baby because it has recognized something foreign (an antigen on the fetal RBC he/she got from dad)
Woman needs a type & antibody screen for EVERY pregnancy at FIRST prenatal visit
99
What is the next step if you have found that a mother has a type of antibodies to fetal RBC which are harmful to the fetus?
Get an antibody titer - the critical titer is usually 1:16 - the antibody titer level which is associated with significant risk of hemolytic disease of the newborn (HDN)
100
What is hemolytic disease of the newborn and how does it occur?
It occurs when the mother is Rh negative and the fetus is Rh positive (father is Rh positive, got Rh factor from there)
If the mother is exposed to the fetal blood she can develop antibodies against the foreign Rh factor on the fetal RBC - the antibodies cross the placenta and attack fetal RBC, causing massive hemolysis = fetal anemia = fetal heart failure & death
101
Name 5+ conditions which cause fetal-maternal bleeding (blood mixing) which can lead to "sensitization" (development of maternal antibodies against fetal RBC)?
```
Chorionic villus sampling
Amniocentesis
Spontaneous/induced abortion
Threatened/incomplete abortion
Ectopic pregnancies
Placental abruption/bleeding placental previa
Vaginal or cesarean delivery
Abdominal trauma
```
102
Why does hemolytic disease of the newborn happen more frequently with a woman's second pregnancy and not during her first if she was sensitized during her first pregnancy?
Because during the first pregnancy, the maternal Ab against fetal RBC are just developing and the Ab titer levels remain pretty low (less chance of HDN)
During the second pregnancy, the immune system is already primed and ready to go so if it recognizes the D Rh (D) antigen, plasma cells will recognize it immediately and start pumping out tons of antibodies against fetal RBC = massive fetal hemolysis
103
What is the standard management of a D-negative patient with a negative antibody screen?
Antibody screen done at first prenatal visit and 28 wks. If D-negative, RhoGAM given at 28 wks & at time of delivery (if baby is D-positive, test in hospital)
104
During what trimester is the risk of sensitization of the mother's immune system to Rh (D) antigen the highest?
Third trimester
105
What is anti-D IgG and when is its use indicated?
Anti-D IgG is an antibody (immunoglobulin) against the Rh factor
It is given to mother's who are NOT sensitized at 28 weeks and 72 hours prior to delivery IF infant is D-positive (test when in hospital for L&D)
(ie immune system has not formed antibodies against Rh factor yet) so that the Anti-D IgG can bind all of the fetal RBC with Rh factor in maternal circulation and hide it from the mother's immune system it doesn't recognized it and make antibodies agains it, thereby preventing the possibility of hemolytic disease of the newborn
It is NOT indicated for patients who already have anti-D antibodies and are sensitized
106
What is the management of a sensitized mother who is D-negative?
1. Screen for antibodies. If positive, find out which type.
2. If anti-D, order a titer level:
> 1:16 is critical - do amniocentesis
< 1:16 is stable - antibody titer Q4 wks
3. Look at results of amnio:
Fetal cells analyzed for D-status
Perform MCA doppler (low flow = anemia)
4. Serial US monitoring for:
Scan for fetal hydrops (collection of fluid 2+ areas)
MCA doppler for presence of severe anemia
Consider fetal RBC transfusion if very premature
5. Delivery:
Mildly anemic - delivery at 37 wks
Moderately/severely anemic - deliver at 32-34 wks
Steroids to mom to enhance fetal lung maturity
107
What are braxton - hicks contractions?
Irregular, non-rhythmic, usually painless contractions that begin at early gestation and increase as term approaches - may make it difficult to distinguish between true and false labor
108
Preterm labor definition
GA <37 weeks w/ regular uterine contractions and progressive cervical change
109
Risk factors for preterm labor
(BFTP: Definition = GA <37 weeks w/ regular uterine contractions and progressive cervical change)
```
Prior hx preterm delivery
Polyhydramnios
Multiple gestations
Substance abuse
Systemic infection
Vaginal Infections
Placental abruption
History of cervical surgery
```
110
Management of preterm labor
Evaluate for causes (infection, abruption etc)
Confirm GA of fetus via US
Look at cervical length (> 30 mm - low risk, <20 mm high risk) & fetal fibronectin assay (from posterior fornix - if negative, 99% predicability for no preterm delivery within 1 week)
```
Stay hydrated (dec uterine irritability)
Administer tocolytics
```
111
What do tocolytic agents do? When are they used? Name some tocolytics
Tocolysis is the pharmacologic inhibition of uterine contractions - do NOT dec neonatal morbidity/mortality but buy you some time (2-7d) to give steroids to mom (if 24-34 wks - for fetal lung maturation) and transfer to hospital with NICU (if < 34 wks gestation)
Agents: Magnesium sulfate, nifedipine, Terbutaline
112
What has the administration of corticosteroids shown do decrease the risk of in the fetus
(Remember given to mothers in preterm labor AKA 24-34 wk GA)
It has been shown to decrease incidence of respiratory distress syndrome (RDS) and intraventricular hemorrhage
113
Which drug is given for neuroprotection if the mother is at high risk of imminent preterm (GA 24-34 wks) delivery?
Magnesium sulfate (at different dosing regimen than if giving for tocolysis)
4gm bolus followed by 1g/hr maintenance
114
What is the most common diagnosis associated with preterm labor?
Preterm premature rupture of membranes (PPROM)
115
What is PROM?
PROM = premature rupture of membranes AKA rupture of membranes BEFORE the onset of labor
116
What is PPROM?
PPROM is preterm (<37 wks) premature rupture of membranes
117
What is prolonged rupture of membranes?
ROM > 18 hours
118
What is the etiology of PROM?
Vaginal and cervical infections
Incompetent cervix
Nutritional deficiencies
119
What is the most concerning complication(s) of PROM?
CHORIOAMNIONITIS!!!
(Infection of the fetal membranes: amnion and chorion)
Premature delivery & associated complications
Placental abruption
120
What is oligohydramnios?
```
Oligo = few/scanty
Amnio = fetal membrane
Hydro = fluid
```
Therefore oligohydramnios is deficiency of amniotic fluid, which is the opposite of polyhydramnios
121
Management of PROM
AVOID VAGINAL EXAMS - they inc risk of chorioamnionitis
Evaluate pt for chorioamnionitis - Fever, WBC count, maternal or fetal tachycardia, uterine tenderness, malodorous vaginal discharge
IF chorioamnionitis - delivery is performed regardless of GA, and broad-spectrum ab are initiated (ampicillin w/ gentamycin)
122
An 18-year old G1P0 at 30 wks gestation presents to triage with complaints of clear amniotic fluid leaking from her vagina - exam positive for pooling, ferning, and nitrazine - cervix is closed on speculum exam. US shows a breech singleton fetus - what is best next step in management?
This patient has PPROM and therefore should be admitted to the hospital for steroids (< 34 weeks = dec risk fetal RDS), and given ABX to increase latency period
123
Workup of third trimester bleeding...
Get good history (how much blood, ABD trauma?)
Get VITALS - hypotensive, tachycardic? ==> hypovolemic!
Labs: CBC (H/H), Type & Screen, Coags, UA, drug screen
Imaging: Ultrasound to look for placenta previa & to monitor fetal well-being
Use "Apt" test to determine if it is fetal blood or maternal blood --> maternal turns brown, fetal turns pink
124
Ddx third trimester bleeding
```
Placental abruption
Placenta previa
Uterine rupture
Vasa previa/velamentous insertion
Circumvillate placenta
Extrusion of cervical mucus ("blood show")
DIC
```
Cervicitis
Neoplasm
125
What lab value abnormalities would support the diagnosis of DIC in third trimester bleeding?
Low platelets
HIGH D-DIMER
Prolonged PT and/or PTT
126
What is the most common cause(s) of third trimester bleeding?
Placenta previa
| Placental abruption
127
Pregnant woman + Pain + vaginal bleeding = what until proven otherwise?
Placental abruption
128
What is placental abruption?
Premature separation of the placenta from the uterine wall before delivery of the baby
129
What is vasa previa?
Vasa previa is a condition in which fetal blood vessels cross or run near the internal opening of the uterus. These vessels are at risk of rupture when the supporting membranes rupture, as they are unsupported by the umbilical cord or placental tissue.
Risk factors include in vitro fertilization
Think placenta previa is when placenta is over uterine opening, vasa (vein) previa = vessels over uterine opening
130
Whose blood is lost with a ruptured vasa previa?
The fetal-placental blood circulation >>> maternal blood
131
RF for placental abruption
```
Trauma (MVA, domestic violence)
Previous history of abruption
Preeclampsia, chronic HTN
Substance abuse (cocaine, cigarettes)
High # parity
```
132
Diagnosis of placental abruption
Via ultrasound will see retroplacental hematoma - supports the diagnosis but not always seen so clinical findings are most important
133
Management of pregnant woman (35 weeks) w/ DIC?
Transfuse blood products (PRBCs, platelets, FFP) & expedite a VAGINAL delivery - want to AVOID c-section (major surgery) in setting of DIC
134
CP Placental abruption
Vaginal bleeding (minimal to life-threatening)
Constant, severe abd pain
Irritable, tender, hypertonic uterus
Evidence of fetal distress (if severe)
Maternal shock
Disseminated intravascular coagulation (DIC)
135
What percentage of placental abruptions present without vaginal bleeding because the bleeding is concealed?
20%!
136
Management of placental abruption
Correct shock (IV fluids, pRBC, FFP, CPP, plt)
Maternal oxygen
Expectant management (close obs w/ ability to deliver immediately if necessary)
If fetal distress --> C-section. If not, can try vaginal.
137
What is placental previa? Etiology?
Condition in which placenta is implanted in the immediate vicinity of the cervical os
Etiology: Unknown, but a/w IVF PREGNANCIES!!! mulitparity, AMA, previous abortions, previous hx placenta previa, previous c-section
138
Clinical presentation placenta previa
PAINLESS bleeding in 2nd-3rd trimester
If pt has not had a 2nd trimester US, DO NOT PERFORM DIGITAL VAGINAL EXAM UNTIL US SHOWS PLACENTAL LOCATION
PAINFUL bleeding = placental abruption
PAINLESS bleeding = placenta previa
139
Diagnosis of placenta previa
Transabdominal US (95% accurate). Transvaginal helps further define location if needed.
MRI - good modality to diagnose but costly & limited availability - therefore most useful when placenta accrete is suspected (can see level of tissue invasion of the placenta)
140
US reveals anterior placenta previa in patient with two prior cesarean deliveries - what are you suspicious of?
Placenta accreta
141
Which two fetal conditions cause third trimester vaginal bleeding?
Vasa previa
When fetal blood vessels cross or run near the internal opening of the uterus. These vessels are at risk of rupture when the supporting membranes rupture, as they are unsupported by the umbilical cord or placental tissue.
Velamentous cord insertion
(fetal vessels insert in the membranes and travel unprotected to the placenta, with no protection from wharton's helly. THis leaves them susceptible to tearing when the amniotic sac ruptures (Incidence: 1% of singleton's, 10% of twins)
142
Clinical presentation of vasa previa or velamentous cord insertion
Vaginal bleeding WITH fetal distress
143
Management of vasa previa rupture or velamentous cord insertion rupture?
Correction of shock and immediate delivery (usually via cesarean section)
144
When is trial of labor after cesarean section (TOLAC) contraindicated?
With hx of prior classical cesarean or if pt has classical uterine scar, TOLAC is CONTRAINDICATED
145
What is uterine rupture and what are some risk factors?
Disruption of the uterine musculature through all of its layers, usually with part of the fetus protruding through the opening
Risk factors: Prior uterine scar from cesarean delivery = MOST IMPORTANT RISK FACTOR 2/2 scarring of the active, contractile portion of the uterus
Low transverse scar < 1% risk
Can occur in setting of trauma
146
CP uterine rupture
Non-reassuring FHT or bradycardia = the MOST suggestive finding of uterine rupture
Sudden cessation of uterine contractions
"Tearing" sensation in the abdomen
Vaginal bleeding
Presenting fetal part moves higher in pelvis
Maternal hypovolemia from concealed hemorrhage
147
Management uterine rupture
Immediate laparotomy and delivery
| May require a cesarean hysterectomy if uterus cannot be reconstructed
148
What is the "bloody show" and is it dangerous?
The "bloody show" is the small amount of bleeding mixed with cervical mucus which often occurs at the onset of labor - it is not dangerous - it is from tearing of a few small vessels as consequence of effacement and dilation of the cervix
149
Complications of uterine rupture
Maternal: Hemorrhage, hysterectomy, death
Fetal: Permanent neurologic impairment, cerebral palsy, death
150
Most common cause of postpartum hemorrhage
Uterine atony (no tone in uterus after birth - usually contracts & is hard to close off blood vessels & prevent bleeding)
151
Definition of early postpartum hemorrhage
During first 24 hours is "early" PPH, past 24 hours to 6 weeks is "late" PPH
Hemorrhage = Excessive bleeding that makes pt symptomatic and/or results in signs of hypovolemia
OR Blood loss > 500 mL in vaginal delivery, >1,000 mL for cesarean delivery
152
Etiology of postpartum hemorrhage
```
CARPIT
Coagulation defect
Atony of uterus
Rupture of uterus
Placenta retained
Implatation site bleeding
Trauma to genitourinary tract
```
```
OR - the 4 T's of PPH:
Tissue: Retained placenta
Trauma: Instrumentation, laceration, episiotomy
Tone: Uterine atony
Thrombin: Coagulation defects, DIC
```
Cause of PPH should be sought out immediately
153
Management of PPH
Compress & massage the uterus, check for retained placental parts & that uterus is intact (no rupture)
If uterus feels BOGGY and not hard, suspect uterine atony as the etiology of PPH (MCC of PPH) - give dilute oxytocin (= uterine contraction)
Uterine artery ligation, hysterectomy if still bleeding
Standard hypovolemia care: Large bore IV x2, isotonic crystalloids, type & cross, vitals, in & outs
Consider coagulopathy if perrsistent bleeding with above management - uterine packing until FFP and CCP are available - AVOID hysterectomy if coagulopathy (further surgery)
154
Placental attachment disorders:
| Placenta acretta vs increta vs percreta
Placenta....
```
Accreta = attaches to myometrium
Increta = invades into myometrium
Percreta = penetrates though myometrium
```
155
Etiology of placental acreta, increta, percreta
Placental acreta, increta, percreta are associated with:
Placenta previa
Previous cesarean delivery (inc #, inc risk)
Previous D&C
Grand multiparity (>5 parity)
All of which are associated with hemorrhage in third stage of labor - treatment of choice is hysterectomy
156
Uterine inversion
Medical emergency
Etiology: Occurs 2/2 excessive cord traction during placental delivery or abnormal placental implantation - morbidity results from shock and sepsis
Incidence: 1/2200 births
Management: Call for help, administer anesthesia, large-bore IV, Don't remove placenta until uterus replaced, stop uterotonic medications, give uterine relaxants, try to replace inverted uterus by pushing on the fundus toward the vagina, oxytocin after uterus is restored and anesthesia is stopped
157
Antepartum: Indications for genetic testing
Indications
AMA
Pervious child with abnormal karyotype
Known parental chromosome abnormality
Fetal structural abnormality on sonogram
Unexplained intrauterine growth retardation (IUGR)
Abnormal quad screening
Techniques:
FISH, karyotyping
158
What is the targeted weight gain for a woman during her pregnancy? What is the most important dietary supplement she should be taking & why?
25-35 lbs
< 15 lb weight gain can cause IUGR
> 40 lb weight gain = inc morbidity
FOLIC ACID!!! --> Prevents neural tube defects - neural tube formed by time of missed period -therefore MUST start supplementing WAY BEFORE that
159
Risk factors for IUGR
```
Poor nutrition
Substance use - tobacco, drugs, alcohol
Thrombophilia
Preeclampsia
Chromosomal abnormalities
Placental infarction/hematoma
Infections
Multiple gestations
```
160
What dietary supplement is recommended in the second and third trimester?
Iron!
Many women develop iron-deficiency anemia during preg due to increased hematopoietic demands of mother and baby
Vegans need to additionally supplement vitamin B12, iron & zinc
161
Why must women limit caffeine intake to 1 cup/day?
> 300 mg/day caffeine may increase the risk of spontaneous abortion - risk increases proportionally w/ amount of caffeine ingested
162
In general, no data exists to support that a pregnant woman must decrease the intensity of her exercise or lower her target heart rate - BUT certain scenarios exercise can be dangerous - name three scenarios in which exercise is contraindicated
```
Evidence of IUGR
Persisten vaginal bleeding
Incompetent cervix
Risk factors for preterm labor
Rupture of membranes
Pregnancy-induced HTN, preeclampsia/eclampsia
```
163
34 wk pregnant woman comes in complaining of leg cramps - management?
Leg cramps occur in 50% of pregnant women, especially in T3 - management is stretching the affected muscle groups and massage
164
When is the safest time to travel in pregnancy?
T2 - past possible miscarriage complications in T1 and not yet encountered risk of preterm labor of T3
Must attempt to stretch lower extremities and stretch for 10 min every 2 hours to avoid DVTs
No air travel after 35 weeks
If traveling abroad, use usual precautions regarding ingestion of un-purified water and raw foods - appropriate vaccines should be given
165
Which vaccines should be avoided in pregnancy?
Any LIVE vaccines - MMR, varicella, oral polio, intranasal influenza
Try not to get pregnant for 4 weeks after getting these vaccines too
Flu vaccine (NOT live nasal mist) is safe at ANY time because benefits outweigh the risks
166
Are immunoglobulins safe in pregnancy? If so when/why are they given?
Immunoglobulins are safe in pregnancy and recommended for women exposed to measles, hepatitis A and B, tetanus, varicella, and rabies
167
Risk factors for uterine atony
RF FOR ATONY = ATOMY
```
Anesthesia, amnionitis
Twins or prolonged pregnancy
Overly long/difficult labor
Macrosomia, multiparity
Polyhydramnios
```
Just think everything too big/too much/lots = uterus cannot contract like it's supposed to - it was stretched too much by big baby, twins, too much fluid, being stretched out too much before (multiparity), gets tired b/c of long labor & can't contract etc
168
First stage of labor - beginning to end
Begins with onset of uterine contractions of sufficient frequency, intensity, and duration = effacement and dilation of cervix
Ends with cervix is completely dilated to 10 cm
169
What are the two phases of the first stage of labor?
1. Latent phase: begins with onset of labor and ends at 4-6 cm dilation --> Considered prolonged if nulliparous > 20 hrs, multiparous >14 hours
2. Active phase: rapid dilation - begins at 4-6 cm dilation and ends at 10 cm - classified according to rate of cervical dilation - acceleration phase, phase of maximum slope, deceleration phase
170
When does fetal descent begin?
During first stage of labor when cervix is at 7-8cm dilation in nulliparious & becomes more rapid after 8 cm
171
What is the minimal average duration of cervical dilation from 4-10 cm
Minimal normal rate of cervical dilation from 4 to 10 cm (active phase of first stage):
1. 2 cm/hr nulliparous
1. 5 cm /hr multiparous
If progress during the active phase of first stage is slower than these figures, evaluation for adequacy of uterine contractions, fetal malposition or cephalopelvis disproportion should be done
172
What is the second stage of labor?
Fetal expulsion - begins when cervix is fully dilated & ends with the delivery of the fetus
Average time - nulliparous < 2 hrs (3 w/ epidural), multiparous < 1 hours (2 w/ epidural)
173
What is the third stage of labor?
Placental separation
Begins immediately after the delivery of the fetus & ends with the delivery of fetal & placental membranes
**Usually < 10 min. If 30 min have passed without placental delivery, manual removal of the placenta may be required
174
What are the three signs of placental separation?
1. Gush of blood from vagina
2. Umbilical cord lengthening
3. Fundus of the uterus rises up & becomes firm
175
When does the ROM usually occur spontaneously?
It usually occurs in the active phase (cervix >4-6 cm) of first stage of labor
176
How to assess for ROM?
+ Pooling in posterior fornix
+ Valsalva = fluid out of os w/ valsalva
+ Ferning = fern pattern on slide (false + w/ blood, semen, trichomonas infection)
+ Nitrazine = Paper turns blue = basic pH of amniotic fluid
Presence of these factors means membranes are probably ruptured & that the fluid noted on exam is probably amniotic fluid
177
Cervical Exam: Dilation - what is it?
Describes the size of the opening of the cervix at the external os
178
Cervical Exam: Effacement - what is it?
Describes the length of the cervix - usually 3-4 cm- but... with labor the cervix thins out & length is reduced
The cervix is said to be 50% effaced when it's length has shortened by 50% ( ~2 cm)
When it becomes as thin as the adjacent lower uterine segment, it is 100% effaced
179
Cervical Exam: Station - what is it?
Describes the degree of descent of the presenting part in relation to the ischial spines, which are designated at "zero" station
Ranges from -3 to +3. Positive stations describe fetal descent below the ischial spine. Each point on the scale represents 1 cm.
180
Cervical Exam: Consistency
Goes from: Firm --> medium --> soft during labor, in preparation for dilation and labor
181
Cervical Exam: Position
Describes the location of the cervix with respect to the fetal presenting part - it is classified as:
Posterior - difficult to palpate because it is behind the presenting part, and usually high in the pelvis
Midposition
Anterior - easy to palpate, low in pelvis
During labor, cervical position progresses from posterior to anterior
182
What agent is used for cervical ripening?
Vaginal prostaglandins
183
What drug is used to increase strength and frequency of contractions?
IV Pitocin
184
Fetal presentation
Describes the presenting part of the fetus:
Vertex is head first (posterior fontanelle)
Brow is eyebrows present first
Face is face first - fetal neck sharply extended
Breech is butt first
185
What to do with breech presentation
If at 31 weeks (not in labor) recheck at 36 weeks & then attempt external cephalic version if persistently breech . < 34 weeks, malpresentation is common (up to 15%) & not significant - most will spontaneously convert to vertex as term approaches
If at term, most frequent management is to do cesarean section - can try to deliver vaginally if other factors favorable and it is a frank breech (complete/incomplete NOT delivered vaginally!!! = HIGH RISK UMBILICAL CORD PROLAPSE)
186
Risk factors for breech presentation
In general think things that make the baby small -
Low birth weight (30% of breeches)
Congenital anomalies (hydrocephalus, anencephaly)
Preterm pregnancy
Multiple gestation
Oligohydramnios, hydramnios
Placenta previa
187
Types of breech presentations
Complete - criss crossed legs, knees bent
Incomplete - one leg up, one leg down
Frank - both legs up & extended fully, flexed at hips
NOTE: Complete and incomplete breeches NOT DELIVERED VAGINALLY - HIGH RISK OF UMBILICAL CORD PROLAPSE
188
Cardinal movements of labor
Engagement - fetal head thru plane of pelvic inlet (-2)
Descent - fetal head down into pelvis (0)
Flexion - chin to chest of fetus
Internal rotation - turning of fetal head towards pubic symphysis
Extension - after fetal head is at maternal vulva, fetal head extends fully to deliver the rest of the head
Restitution (External rotation) - - fetus turns face forward so that occiput is in line with the spine
Expulsion - delivery of anterior shoulder, then the rest of the fetus
189
Describe different degrees of perineal lacerations
First degree: Perineal skin & vaginal mucosa torn, muscle & underlying fascia intact
Second degree: First degree + fascia & muscle of perineal body but NOT the anal sphincter
Third degree: Second degree + involvement of anal sphincter
Fourth degree: Extends thru rectal mucosa to expose the lumen of the rectum
NOTE: Proper repair/closure of 3rd/4th degree is essential to prevent future fecal incontinence and rectovaginal fistula
190
Types of episiotomies & benefits/risk of each
NOT standardly performed anymore - in special cases only like shoulder dystocia
Types = midline vs mediolateral
Midline: Most common. Inc risk 4th deg lac
Mediolateral: Causes more bleeding/pain
191
Monitoring during labor
Uterine contractions - external vs internal monitors
| Fetal heart rate -
192
MCC maternal mortality in western world
PPH
193
What is considered a "reactive" fetal heart tracing?
15 bpm above the baseline lasting 15 seconds
Need two of these in 20 minutes = indicates well-oxygenated fetus with intact neurological & cardiovascular system
Normal rate: 110-150
194
What are early decelerations and what causes them?
Early decels are decelerations in FHR that occur WITH the uterine contraction
They are due to head compression - they are clinically benign and no intervention is necessary
195
What are late decelerations and what causes them?
FHR decelerations which occur AFTER the uterine contraction has ended - due to UTEROPLACENTAL INSUFFICIENCY (not enough OXYGEN) - can follow epidural (hypotension) or uterine hyperstimulation
Management: O2, lateral decubitus position, pitocin off, close monitoring
196
Variability of FHR - absent vs mild vs moderate vs marked
What causes decrease in beat to beat variability?
Beat to beat FHR variability (BTBV) is the single most important characteristic of the baseline FHR
Absent - amplitude undetectable
Minimal - amplitude 0-5 beats
Moderate = amplitude 6-25 beats
Marked = amplitude > 25 beats
```
BTBV decreases with:
Fetal acidemia
Fetal asphyxia
Maternal acidemia
Drugs (Narcotics, MgSO4, barbiturates)
Acquired or congenital neurologic abnormality
```
197
What do you do if you note an abnormal labor pattern?
Assess the three P's:
Power (contractions - adequate?)
Passenger (fetal size & position good for vaginal delivery?)
Pelvis (adequate for normal vaginal delivery?)
198
What does NO beat to beat variability on FH monitoring mean?
It means fetal acidosis & the fetus MUST be delivered immediately
199
Episiotomy care
Ice pack for first several hours (dec edema/pain)
At 24 hours, moist heat (sitz bath)
Typically well-healed by week 3
200
APGAR components
Activity (muscle tone)
Pulse (absent, <100, >100)
Grimace (reflex irritability)
Appearance (skin color - blue, pink body blue ext, pink)
Respirations (absent, slow, vigorous cry)
201
CP & Management Endometritis
CP: Fever, fundal tenderness, and foul-smelling lochia - MC 2-3 days postpartum
Management: Broad spectrum abx
202
Risk factors for endometritis
```
Cesarean delivery
GBS colonization (leads to 80% greater likelihood)
Prolonged ROM (>18 hours)
Prolonged labor
DIabetes
Multiple cervical exams
Manual extraction of placenta
Chorioamnionitis
Internal monitoring
```
203
Spontaneous abortion - def, etiology, RF
Pregnancy loss < 20 wks gestation. Most are in first trimester due to chromosomal abnormalities. Types of spontaneous abortion include threatened, inevitable, incomplete, complete, missed, septic & recurrent (see other cards to follow)
Etiology:
1. Chromosomal abnormalities (aneuploidy, triploidy etc)
2. Unknown
3. Infections (think STDs)
4. Anatomic defects (uterine, cervical incompetence, leiomyomas (fibroids), intrauterine adhesions etc)
5. Endocrine factors (progesterone deficiency, PCOS, uncontrolled diabetes)
RF: AMA, smoking, prior hx spontaneous abortion
204
Threatened abortion
Uterine bleeding from a gestation that is <20 wks w/o cervical dilation or passage of tissue
Exam: CLOSED cervical os WITHOUT products of conception or amniotic fluid in endocervical canal
Management: Observation, pelvic rest
205
Inevitable abortion
Vaginal bleeding, cramps, and CERVICAL dilation at < 20 weeks conception WITHOUT products of conception
Management: D&C or misoprostol (prostaglandin E1)
206
Incomplete abortion
Pass age of some, but not all, products of conception from uterus before 20 wks gestation. Inc risk of ongoing bleeding requiring a blood transfusion and inc risk ascending infection.
Dx: Cramping &Bleeding, enlarged boggy uterus w/ DILATED internal cervical os - POC present in endocervical canal or vagina, w/ POC retained in the uterus seen on US.
Management: Assess HD stability & stabilize
Suction D&C to remove POC from uterus or medical evacuation with misoprostol - ONLY IF STABLE. Karyotype POC if recurrent abortion.
207
Complete abortion
Complete passage of POC - cervical os re-closes after the abortion is complete.
Pain has ceased, uterus well-contracted, cervical os may be closed, US shows empty uterus
Management: Observe patient
208
Missed abortion
Missed abortion is fetal demise before 20 wks of gestation without expulsion of any POC
The pregnant uterus fails to grow and sx of preg disappear. Intermittent vaginal bleeding/spotting/brown discharge & a closed cervix
B-hcg quant may decline, plateau, or continue to inc
Managemet: Most will spontaneously deliver w/in 2 wks, Risk of incomplete or septic abortion may require a suction D&C. Misoprostol if want medical evacuation of the uterus.
209
Septic abortion
More likely with induced abortions
Polymicrobial infection
Can spread from endometrium to peritoneum
Septic shock may occur, esp if all POC are not removed
210
Ddx T1 bleeding
Spontaneous abortion
Ectopic pregnancy
Molar pregnancy
Vaginal/cervical lesions/lacerations
211
Ddx T3 bleeding
Uterine rupture
Rupture of vasa previa
Placental abruption
Placenta previa
212
Pharmacologic agents for pregnancy termination - T1 vs T2
Mifepristone and misoprostol used in T1
Prostaglandins used in T2
Remember M before P in alphabet
Note: Complications for T2 abortions are 4x higher than T1 abortions
213
Surgical methods of pregnancy termination
May be used in T1 or T2
Dilation & evacuation - Evacuation is via curettage in T1, (D&C) via other instruments in T2
D&E is the SAFEST form of pregnancy termination in T2 (better than prostaglandins) b/c has decreased maternal mortality compared to PGE induction
Note: Complications for T2 abortions are 4x higher than T1 abortions
214
What form of prostaglandin is contraindicated for pregnancy termination in specific subset of pt with lung disease?
PGF2a is contraindicated in asthmatics because it induces smooth muscle contraction
215
MC site of ectopic pregnancy
Fallopian tubes (97%) w/ AMPULLA of tubes being mc site inside the tubes
216
Ectopic pregnancy more common in younger women or older women?
4x more common in women > 35 YO compared to 15-24 YO group
Note: Ectopic preg is the LEADING cause of pregnancy-related death
217
RF ectopic pregnancy
```
Prior ectopic pregnancy = #1 RISK FACTOR
PID, STIs
Current IUD use
Septate uterus
Current smoking
Tubal scarring form prior surgery (sterilization)
DES exposure
```
218
PE Ectopic
Vaginal bleeding
Pelvic pain
Adnexal mass
Si rupture ectopic: Hypotension, tachy, rebound, guarding
219
Ddx ectopic pregnancy
```
Ovarian torsion
Threatened abortion
PID
Acute appendicitis
Ruptured ovarian cyst
Tubo-ovarian abscess
Degenerating uterine leiomyoma (fibroid)
```
220
Dx studies ectopic pregnancy
Transvaginal ultrasound = imaging modality of choice for diagnosing ectopic pregnancies
221
Do b-hcg levels correlate with the size of the ectopic pregnancy/potential for rupture?
NO
B-hcg also doesn't correlate with the location of hte ectopic or the GA of the ectopic
222
Management of ectopic pregnancy
```
Assess hemodynamic stability of pt
Assess if ectopic is ruptured or not
Medical management = methotrexate - for early ectopic
Surgical - if stable - Laparotomy
Surgical - if unstable - Laparoscopy
```
223
Chadwick's Sign
Bluish discoloration of vagina and cervix during pregnancy
224
Goodell's Sign
Softening and cyanosis of hte cervix at or after 4 weeks
225
During what gestational age is placental abruption most likely to occur?
24-28 weeks GA
