OB MTB Flashcards
embryo is considered fetus at how many weeks gestation?
how long infant for?
8 weeks
infant for 1 year after birthNagele rule
Nagele rule
EDD : LMP - 3 months + 7 days
gestational age?
trimester breakdown
number of days since LMP
1st: 0-12 weeks (14 gestational age)
2nd: 12-24 weeks
3rd: 24-delivery
screening based on trimesters
1st: FHTs with Doppler
2nd: triple/quad screen, movement at 16-20 wks, u/s at 18-20 wks GA
3rd: frequent visits, monitor labs
Gs and Ps of female who presents with her 6th pregnancy, has had 2 abortions, 2 children born at term, and set of twins born preterm
G6P2124
G TPAL
(twins born preterm count as 1 pregnancy)
one of first signs of pregnancy on PE
Goodell sign: softening of cervix, may be felt at 4 weeks
in contrast, quickening is first time mother feels fetal movement
other signs of pregnancy
Ladin:
Chadwick:
chloasma:
Ladin: softening of midline uterus (6 wks)
Chadwick: blue discoloration of vagin and cervix (6-8 wks)
chloasma: “mask of pregnancy” (16 wks)
how rapidly is B-hCG produced in 1st trimester?
when does it peak?
doubles every 48 hrs in 1st 4 wks
peaks at 10 wks
drop in 2nd trimester, and rise slowly again in 3rd trimester to levels of 20-30,000 IU/mL
when/what B-hCG level should a gestational sac be seen on ultrasound?
at 5 wks or B-hCG of 1000-1500 IU/mL
changes in CO, HR, BP
^CO, ^HR, decreased BP (lowest 24-28 wks)
changes in coagulation
hypercoagulable, ^fibrinogen
but no increase in PT, PTT, INR
1st trimester tests
see every 4-6 wks
11-14 wks: u/s for GA and nuchal translucency
blood tests, pap smear, Gc/Clamydia
1st trimester screening for chrom. abn.
most accurate test to establish gestational age in 1st trimester
U/S, esp. 11-14 wks
2nd trimester screening
triple/quad screen 15-20 wks
ultrasound 18-20 wks for fetal malformations
3rd trimester visits
q2-3 wks until wk 36 then qwk
27: CBC (iron if hgb less than 11)
24-28: glucose load (140+ 3 hr gtt)
36: cerv. cx for Gc/Chl, recvag cx for GBS
when to get CVS
amniocentesis
CVS: 10-13 wks in AMA or known genetic disease
amniocentesis: 11-14 wks
most common site of ectopic
risk factors?
ampulla of fallopian tube
PID, IUD, previous ectopic
ectopic pregnancy:
presentation and tests
u/l low abdominal or pelvic pain, vaginal bleeding, hypotensive with peritoneal signs if ruptured
tests: B-hCG, U/S, laparoscopy (tx)
unstable ruptured ectopic pts
need IV fluids, +/- blood products, +/- dopamine to stabilize BEFORE surgery
stable ruptured can go straight to sx
medical tx of non-ruptured ectopic
MTX labs: B-hCG, CBC, t/s, LFTs look for 15% drop in hCG in 4-7 days if not, 2nd dose MTX if still not decreasing, resort to surgery
exclusion criteria for MTX
immunodeficiency, noncompliant, hepatotoxicity, 3.5cm+, FH beat auscultated (^risk failure)
ectopic surgical tx
salpingostomy (cutting hole in tube, preserves)
salpingectomy (remove whole tube)
give RhoGAM if Rh negative
etiologies of abortion
*chromosomal abnormalities
anatomic abnormalities, infection (STDs), immune (aPL syndrome), endocrine (HTN, DM), malnutrition, trauma, Rh isoimmunization
tests to do in abortion
CBC, type/screen, U/S
if no products of conception found on u/s ?
if some POCs found ?
if intact POCs but bleeding and cervix dilated?
if intact POCs, no cervical dilation but bleeding?
if intact POCs but fetal death?
infection of uterus/surrounding areas?
complete abortion (f/u)
some: incomplete (D&C/medical)
bleeding/dilated: inevitable (D&C/medical)
bleeding/no dilation: threatened (bed/pelvic rest)
fetal death: missed (D&C/medical)
infection: septic abortion (D&C and IV abx (levaquin, metronidazole)
medical treatment of abortions (incomplete, inevitable, missed)
misoprostol (PGE1 analog): help open cervix and expulse fetus
if Rh- give RhoGAM
complications of multiple gestations
spontaneous abortion of 1 fetus, premature L+D, placenta previa, anemia
preterm contractions with cervical dilations called ?
preterm labor
if “gush of fluids” consider PROM
if just preterm contractions will not lead to cervical change
risk factors for preterm labor
PROM, multiple gestations, previous hx of preterm labor, placental abruption, maternal factors (anatomy, infection, pre-E, intra-abd. sx)
when NOT to stop preterm labor
pre-E/eclampsia, cardiac disease, cervical dilation of +4cm, maternal hemorrhage (placental abruption, DIC), fetal death, chorioamnionitis, between 34-37 wks, greater than 2500g
most commonly used tocolytic
SEs?
Mg+: decreases uterine tone and contractions
SEs: flushing, HA, diplopia, fatigue
also, check DTRs and look out for respiratory depression and cardiac arrest
others: CCBs, terbutaline (B-agonist)
Do NOT use indomethacin
PROM may lead to ?
preterm labor, cord prolapse, placental abruption, chorioamnionitis (do fewer pelvic exams to reduce risk of chorio)
treatment of PROM
if chorioamnionitis: deliver NOW
if term and no chorio: wait 6-12 hrs for spontaneous delivery, than induce
P-PROM treatment (preterm premature ROM) if no chorioamnionitis
betamethasone, tocolytics, ampicillin, 1 dose azithromycin (decrease risk of dev. chorio)
if PCN allergic: cefazolin and azithromycin
if high risk anaphylaxis: clindamycin and azithromycin
PAINLESS vaginal bleeding
placenta previa
abnormal implantation over internal os
cause of 20% of hemorrhages
^risk with previous C-section, uterine sx, gestations, placenta previas in past
types of placenta previa
complete, partial, marginal (adjacent, touching edge), vasa previa (fetal vessels over os), low-lying placenta (between 0-2 cm away)
treatment of placenta previa
strict pelvic rest
immediate C-section if: cervix dilated +4cm (unstoppable labor), severe hemorrhage, fetal distress
get type/screen, CBC, PTT
PAINFUL vaginal bleeding
placental abruption
may occur before, during, after labor (most commonly in 3rd trimester)
may present with contractions and possible fetal distress
risk factors for placental abruption
HTN, prior abruption, cocaine use, external trauma, smoking during pregnancy
types of placenta previa
concealed (blood in uterine cavity) and external
risks with placenta abruption (most likely concealed type)
premature delivery, uterine tetany, DIC, hypovolemic shock, fetal hypoxia/death, Sheehan syndrome (postpartum hypopituitarism
sudden onset EXTREME abdominal pain
uterine rupture
typically occurs during labor
+/- abnormal bump in abdomen, no contractions, regression of fetus
tx: immediate laparotomy and delivery
what ^risk of uterine rupture
previous C-section with classic (longitudinal) incision OR low transverse (current)
trauma (MVAs), myomectomy, overdistension (polyhydramnios, twins), percreta
hemolytic disease of newborn
fetal anemia and extramedullary production of RBCs
^heme and bilirubin in plasma (bili may be toxic)
can lead to erythroblastosis fetalis (^fetal cardiac output (CHF))
Rh screening done when?
initial prenatal visit, if Rh- get Ab titers
no Abs: unsensitized
done again at 28 and 35 wks, if still unsensitized, give RhoGAM at 28 wks and at delivery
Rh- mother is considered sensitized if Ab titers are more than ?
1:4
if the titer is less than 1:16 no further treatment
if more than 1:16: amniocentesis at 16-20 wks to evaluate fetal Rh status
if Rh+ then serial amniocentesis (evaluation of fetal bilirubin level)
eclampsia treatment
(pre-E + tonic-clonic seizure)
stabilize mom then deliver
Mg+ sulfate and hydralazine
complications of pregestational DM
^risk: pre-E, spontaneous abortion, rate of infection, PPH, congenital anomalies, macrosomia
fetal testing in pregestational DM
32-36 wks: weekly NST (FWB) and U/S (fetal size)
36+ wks: 2x weekly (1 NST and 1 BPP (for amniotic fluid amount, FWB)
37 wks: L/S ratio, if mature, deliver
38-39 wks: deliver
GDM complications
preterm birth, macrosomia (dystocia), neonatal hypoglycemia (increased glucose in utero raises insulin levels), DM persisting after delivery
testing for GDM
glucose load test at 24-28 wks: 50g glucose, measure 1 hr later
+ if +140 mg/dL, then do glucose tolerance test: 100g glucose, measure fasting, 1,2,3 hrs
if 2/4+ : GDM
when to do more than diet and exercise for GDM
if uncontrolled: fasting +95 mg/dL and 1 hr postprandial greater than 140 mg/dL
tx: insulin: NPH before bed and aspart before meals
if GDM pts don’t want insulin
metformin and glyburide
types if IUGR (bottom 10%)
symmetric: before 20 wks
asymmetric: brain weight NOT decreased, abdomen smaller than head, occurs after 20 wks
etiologies of IUGR
chromosomal abn, NTDs, infection, multiple gestations, maternal HTN, renal disease, malnutrition, substance abuse (*smoking)
complications of IUGR
premature labor, stillbirth, hypoxia, lower IQ, seizures, mental retardation
macrosomic if how big, what to do next?
risk factors?
over 4500g, fundal height at lease 3 cm more than age, get an U/S to estimate weight by femur length, abd. circumference, head diameter
DM or obesity, AMA, postterm
reactive NST defined by
detection of 2 fetal movements
2 accelerations of FHR greater than 15 bpm lasting 15-20 seconds over 20-min period
BPP consists of
NST
fetal chest expansion (1+ in 30 min)
fetal muscle tone
amniotic fluid index (AFI) based on sonogram
each worth 2 pts, 8-10 is normal, 4-8 inconclusive, below 4 is abnormal
normal FHR
110-160 bpm
early decelerations
decrease in HR occurs with contractions due to head compression
variable decelerations
decrease in HR and return to baseline with NO RELATIONSHIP to contractions
implies umbilical cord compression
mnemonic for accels/decels
VEAL CHOP Variable - Cord compression Early - Head compression Accel - OK Late - Placental insufficiency
late decelerations
decrease in HR AFTER contraction started, no return to baseline until contraction ends
implies fetal hypoxia/placental insufficiency
stage 2 steps
- engagement 2. descent 3. flexion
- internal rotation 5. extension 6. external rotation
- delivery of anterior shoulder
- delivery of posterior shoulder
How to induce labor
Prostaglandin E2: cervical ripening (do not give to asthmatics)
Oxytocin: exaggerates uterine contractions
Amniotomy: puncture sac with hook, but inspect for a prolapsed cord first!
prolonged latent stage
caused by ?
how to treat ?
longer than 20 hours for primi and 14 hrs for multi
causes: sedation, unfavorable cervix, uterine dysfunction with irregular/wk contractions
tx: rest and hydration, most convert to spontaneous delivery in 6-12 hrs
protracted cervical dilation
cause?
treatment?
less than 1.2 cm/hr in primi, less than 1.5 in multi
causes: power, passenger, pelvis
tx: oxytocin or C-section
arrest disorders
no cervical dilation for 2 hrs or no fetal descent for 1 hr
causes: cephalopelvic disproportion (tx: C-section), malpresentation, excessive sedation/analgesia
breech positions:
frank
complete
footling
frank- hips flex knees extended (“frank hot dogs”)
complete -both hips and knees flexed
footling - feet first, single or double
what to do if shoulder dystocia
- McRobert’s maneuver: mom flexes knees into abdomen with suprapubic pressure (Mc = Mom)
- Rubin maneuver: rotation of fetal shoulders by pushing posterior shoulder toward fetal back (Rubin = rotate)
- Woods: same as Rubin but towards fetal head
- deliver posterior arm 5. deliberate fx of fetal clavicle!
- Zavanelli maneuver: push head back and C-section, last resort!
80% of postpartum hemorrhage due to ?
other causes
uterine atony (inadequate compression of uterine blood vessels) others: laceration, retained parts, coagulopathy
risk factors for atony
anesthesia, uterine overdistension (twins, polyhydr.), prolonged labor, laceration, retained placenta (accreta), coagulopathy
what to do if PPH
assure no uterine rupture or retained placental with bimanual exam, then bimanual compression and massage (controls most cases)
administer oxytocin if does not work (will constrict BVs)
if inability to breastfeed after PPH, think ?
Sheehan syndrome
