Obstetrics
How can you tell if mom is having adequate contractions for labor?
*200 montevideo (mV) units in 10 minutes* using an IUPC. May need to try oxytocin first to see if it helps.
Treatment of pyelonephritis in pregnancy
*Admit for Ceftriaxone. Reassess.* If pyelo: - 10 day abx based on cultures/sensitivity if no improvement: - think abscess and tx 14 day abx based on cultures/sensitivity - US for visualization
treatment of asymptomatic bacteriuria in pregnancy
*Amoxicillin* firstline, then *re-screen*. Nitrofurantoin if PCN allergic. teratogenic tx: - TMP-SPX - Ciprofloxacin
How are endometritis/chorioamnionitis treated?
*Ampicillin + Gentamicin* +/- Clindamycin
How much blood loss defines post-partum hemorrhage? What are some causes?
*Blood loss > 500 ml* 1. MC is uterine atony 2. birth trauma 3. retained products of conception
Complete vs Incomplete Mole
*Complete* - 46 XX (paternally derived) from sperm fertilizing an empty ovum. No fetal tissue. *Incomplete* - 69 XXY - when a normal ovum is fertilized by two sperm; contains fetal tissue. May be benign or malignant. Markedly elevated B-hCG with snowstorm appearance on pelvic US with no gestational sac or fetus
What are the diagnostic pertinent values when screening for GDM? 1 hr GTT 3 hr GTT
*Done at 24-28 weeks gestation* 1 hr GTT load of 50 grams = *>/= 140* Then, within 1 week... 3 hr GTT load of 100 grams, needs 2 to confirm: *fasting >/= 95 1 hr >/= 180 2 hr >/= 155 3 hr >/= 140*
If there is an abnormal lie of the fetus, what can be done?
*External cephalic version (ECV)* -- external manipulation to turn fetus from breech to cephalic. Commonly done at 36-38 weeks. 50-60% success. CI: - placenta previa - placental abruption - non-reassuring FHR - significant fetal and uterine anomaly - hyperextended fetal head
What vitamin prevents fetal neural tube defects?
*FOLATE*
What is a complication of untreated hyperthyroid and hypothyroid in pregnancy? How are they treated?
*Hyperthyroid --> fetal demise*. Tx w/ PTU and/or 2nd trimester surgical resection. *Hypothyroid --> Cretinism*. Tx w/ Levothyroxine and test TSH q4wks. 1/3 pts need 25% increase in medication during pregnancy.
What is the treatment of a Preterm labor b/n 20-34 weeks gestation?
*Steroids* for fetal lung development and *tocolytics* to inhibit delivery to allow for lung development.
What is the best diagnostic test after getting a positive pregnancy test at the first prenatal visit? Why? What is an alternate test?
*Ultrasound* - confirms intrauterine vs ectopic pregnancy - gestational age - assesses for multiple gestations If before 10 weeks, may not be able to see by US. If not US, *serum HCG*. Commonly for ectopics, choriocarcinomas, moles, hyperemesis gravidarum.
What 3 diseases should you screen for between weeks 20-28 weeks gestation? How?
*gestational diabetes* using blood sugar at *24-28 wks* *alloimmunization* using Rh antigen status *maternal anemia* using Hgb
What GI changes occur in pregnancy?
- GERD, tx w/ PPI - nausea, tx w/ ondensetron - constipation, tx w/ stool softener + motility agent - Fe deficiency, tx w/ iron supplement + constipation meds - gallbladder disease, tx w/ 2nd trimester cholecystectomy
What should you ask in a first visit for a new OB pt?
- Gravidity Para [tpal] - LMP - PMHx, medications, Surgical Hx, FHx, SHx, allergies To help determine risk factors
Risk factors for Placental Abruption
- HTN - cocaine use - smoking - multiparity - trauma
Trisomy X (Klinefelter's Syndrome)
- One or more extra X chromosomes with the presence of the Y - Male appearance - Often undetected - Manifestations: gynecomastia, small testes and penis, tall stature, increased weight, and sparse body hair - Also associated with learning disabilities, behavioral problems, sexual dysfunction, pulmonary disease, varicose veins, osteoporosis, and breast cancer - Treatment: testosterone
What cardiovascular changes occur during pregnancy?
- decrease systemic vascular resistance (makes "pipes" larger) - decreased BP - increased HR - increased CO - increased # of RBCs - increased plasma (decreases viscosity) - hemoglobin decreases
What GU changes occur during pregnancy?
- increased GFR - decreased creatinine - obstructive uropathy at pelvic brim
What risk factors increase the risk of aneuploidy?
- increased maternal age ( >/= 35) - prevalence greater in younger women due to > # of children
What pulmonary changes occur during pregnancy?
- increased tidal volume - decreased functional residual capacity (due to growing uterus) *Nothing much happens...*
Smoking and secondhand smoke exposure increase the risk of .... ?
- infertility - placental abruption - preterm premature rupture of membranes (PPROM) - placenta previa - low birth weight (100 to 300 grams, depending on the number of cigarettes smoked)
Types of breech presentation
1. *Frank breech*: fetus's hips are flexed with extended knees B/L 2. *Complete breech*: fetus's hips and knees are flexed B/L 3. *Footling breech*: fetus's feet are first: one leg (single footling) or both legs (double footling)
Stage 2 of labor and delivery
10 cm dilation --> delivery of fetus 3 hr (nulli) 1 hr (multi)
When can fetal heart rate be appreciated by pocket Doppler?
11-12 weeks
Where can fundal height be palpated at each week below? 12 weeks 16 weeks 20 weeks
12 weeks -- pubic symphysis 16 weeks -- midway b/n symphysis and umbilicus 20 weeks -- umbilicus
When can a woman feel quickening in pregnancy?
17-19 weeks
How do you screen for aneuploidy in the first and second trimesters?
1st Trimester: - US for *nuchal translucency < 3 mm* - PAPP-A - hCG 2nd Trimester: - *Quad screen: hCG, AFP, estriol, and Inhibin A*
What weeks are equivalent to each trimester?
1st Trimester: 0-14 2nd Trimester: 14-28 3rd Trimester: 28-birth
Preterm gestational age
24 wks - 37 wks
When is GBS screening done? How long is it valid?
35-37 weeks. It is valid for 5 weeks.
Term gestational age
37-42 weeks
When can gestational sac be appreciated?
5-6 weeks
The beginning phase of labor tends to progress slowly. What is the critical value of cervical dilation in which labor begins to progress rapidly?
6 cm dilated
When can the fetal pole and cardiac activity be seen by US?
7-8 weeks
What is the BP goal for HTN pts that become pregnant?
< 140/80
Spontaneous abortion gestational age
< 24 wks (some say 20 wks)
What is the treatment of pPROM?
> 34 wks = deliver 24-34 wks = steroids for fetal lung development < 24 wks = abortion This may lead to prolonged ROM.
Turner Syndrome
A chromosomal disorder in females in which either an X chromosome is missing, making the person XO instead of XX, or part of one X chromosome is deleted. Imaging: streak (of fibrous tissue seen in the expected location) ovaries, renal abnormalities (horseshoe kidneys)
What is a biophysical profile and what are the 5 components?
A fetal biophysical profile is a prenatal test used to check on a baby's well-being. The test combines fetal heart rate monitoring (nonstress test) and fetal ultrasound to evaluate a baby's heart rate, breathing, movements, muscle tone, and amniotic fluid level.
FDA Pregnancy Categories:
A: No risk in controlled human studies B. No risk in controlled animal studies. No available human studies. C: safety of use by pregnant woman is unknown and the drug should not be used unless the potential benefit outweighs the potential risk to the fetus. D. Strong evidence of risk to fetus X: Very high risk to fetus
If pregnancy woman has UTI with GBS at initial visit (because you draw a urine culture), how do you treat?
Amoxicillin and then you can skip the GBS screen at 35-37 wks and treat mom prophylactically.
What is the definition of fetal macrosomnia?
An infant that weighs > 9 pounds or 4500 grams.
What fetal position(s) require Cesarean section?
Any breech positioning, although, not always necessary.
Why should you encourage mom to sleep on left side?
Avoids uterus from compression organs, especially Inferior Vena Cava.
How much weight should a woman gain during pregnancy?
BMI: < 18.5: 1 lbs/wk -- 28-40 lbs total 18.5-25: 0.75 lbs/wk -- *25-35 lbs total* 25-30: 0.50 lbs/wk -- 15-25 lbs total > 30: 0.25 lbs/wk -- 10-20 lbs total Use the quarter system, beginning at the bottom.
Trisomy X (XXX)
Barbie doll woman... results in a fertile "normal" woman with an extra X chromosome clinical features: - long legs - taller than average - delayed developmental speech and language skills - abnormally curved pinky finger - behavior and emotional problems - weak muscle tone - etc
How is a pt w/ DM that becomes pregnant treated before, during, and post-pregnancy?
Before: A1c < 7% w/ diet and exercise 1st line. Change oral medications to insulin (metformin and glyburide ok). During: increased insulin requirement, target post-prandial sugars, do not use A1c Post-delivery: massive decrease in insulin requirement almost immediately after delivery
What labs need to be ordered at the first prenatal visit?
Blood: - blood type - *RH antigens - Hgb/Hct (establish baselines)* - HIV and confirmation if positive - HsBag - RPR (tx w/ penicillins) - Titers of varicella and rubella Urine: - *UA and culture* - proteinuria - GC/Chlamydia Cytology: - pap (if needed) sometimes.. genetic screenings
What biochemical process accounts for the rapid morphological change in the cervix?
Breakage of disulfide bonds.
Why in pre-conception is it important to control DM, HTN, and hypothyroidism?
DM and HTN medications are often teratogenic. Should make sure to get these diseases under control before pregnancy and have pt switched over to safe medications in pregnancy. Hypothyroidism should be controlled due to physiologic changes in pregnancy and increased proteins. Typical levothyroxine dose may need an increase.
What is stage I labor arrest and how is it treated?
Defined as no change in 4 hours of the active stage I or active stage I lasting > 5 hours. Treatment = oxytocin. If fails or pt already has adequate contractions --> C-section
How is prolonged ROM treated?
Deliver GBS + give Ampicillin GBS - then wait FU to evaluate for endometritis or chorioamnionitis
What does a positive Quad screen look like for: Down's Syndrome Edward's Syndrome
Down's (Down is HI): - hCG and Inhibin A are high, AFP and estriol are low Edward's: - everything is low
What are the corresponding chromosomes in the following forms of aneuploidy? Down's Edward's Patau's
Down's = 21 ... drinking age is 21 Edward's = 18 ... election voting at age 18 Patau's = 13 ... PG-13 movies
Risk factors for a high-risk pregnancy:
Existing health conditions, such as high blood pressure, diabetes, or being HIV-positive Overweight and obesity. Obesity increases the risk for high blood pressure, preeclampsia, gestational diabetes, stillbirth, neural tube defects, and cesarean delivery. NICHD researchers have found that obesity can raise infants' risk of heart problems at birth by 15%. Multiple births. The risk of complications is higher in women carrying more than one fetus (twins and higher-order multiples). Common complications include preeclampsia, premature labor, and preterm birth. More than one-half of all twins and as many as 93% of triplets are born at less than 37 weeks' gestation.4 Young or old maternal age. Pregnancy in teens and women age 35 or older increases the risk for preeclampsia and gestational high blood pressure.
What causes cervical change to occur?
Fetal head engagement OR balloon/PGE/oxytocin
What vaccines can a pregnant woman receive?
Flu shot, Hep B
When is the onset of preeclampsia?
From 20 weeks gestation to 6 weeks postpartum. If symptoms occur before 20 weeks, consider a molar pregnancy as a cause of hypertension.
Defined prolonged rupture of membranes.
From ROM to delivery of placenta, the time is *> 18 hours*.
What hormone created by the placenta is thought to cause GDM?
Human Placental Lactogen -- this peaks at 24-28 weeks, which is why we test for GDM in this time frame.
What clotting changes occur during pregnancy?
Hyper coagulability -- allows mom to stop hemorrhaging if it occurs. Bad because it may cause DVTs or PEs.
Indirect Coombs test
Identifies pts sensitized to Rh-positive blood. Test repeated between 24 to 28 weeks of gestation for pts who are Rh-negative and not sensitized.
What are typical causes of PROM, pPROM, prolonged ROM?
Infections like *GBS*
What is the role of magnesium in pregnancy?
It functions as seizure prophylaxis for preeclamptic and eclamptic patients.
When does labor begin?
Labor begins with the onset of regular, rhythmic contractions that lead to serial dilatation and effacement of the cervix.
What vaccines should be avoided during pregnancy?
Live vaccines: MMR and varicella, and live attenuated influenza vaccine
What is the most favorable fetal position?
Longitudinal cephalic longitudinal = alignment w/ mom cephalic = head first
Seven cardinal movements of labor?
Mnemonic is "ED FIREEE" 1. *E*ngagement 2. *D*escent 3. *F*lexion 4. *I*nternal *R*otation 5. *E*xtension 6. *E*xternal Rotation 7. *E*xpulsion
Gestational Diabetes Mellitus (GDM): path, pt, dx, and tx
Path: Diabetes that starts *after 20 weeks* of gestation. Pt: everyone gets screen but increased risk in BMI > 30, GDM hx, pre-diabetic Dx: A1c is NOT good for GDM. Use *1-hr GTT to screen* (+ is >/= *140*). Then confirm with 3-hr GTT Tx: *insulin* is gold standard, can use Metformin and Glyburide
What is the treatment for a positive GBS in pregnancy?
Penicillin G 5 million units IV x1 then 2.5-3 million units IV q4h until delivery. If PCN allergic, cefazolin or clindamycin.
What infection might mom get due to prolonged ROM?
Prolonged ROM allows vaginal flora to ascend into mom's uterus. If baby is still in utero --> *chorioamnionitis* If baby has been delivered --> *endometritis* Mom will be feverish and look toxic!
How are endometritis/chorioamnionitis diagnosed?
RULE OUT other infections w/ UA, CXR, and blood CX.
When is Rhogam administered?
Rh negative mom: 28 weeks Postpartum (within 72 hours of delivery) After procedures (within 72 hours) - miscarriage, elective abortion, HUBS/amnio/CVS, placental abruption, placenta previa, trauma
What is the MOA of RhoGAM?
RhoGAM is an immunoglobulin for Rh incompatibility. It suppresses the immune response of Rh-negative pts to Rh-positive RBCs. containing IgG anti-D (anti-Rh) for use in preventing Rh immunization. Binds to the Rh antigen to prevent the body from making antibodies.
What is a normal manifestation of ROM?
Rush of fluid (a lot) that may have meconium, blood, and/or be clear.
FU abortion care
Serum HCG to show < 5. If between 5-20, continue monitoring levels. If it does not trend down to < 5, then D&C or medication (misoprostol) to complete abortion. Complications: Septic abortion
How is ROM diagnosed?
Speculum = pooling Nitralazine turns pH paper blue Microscopy = ferning U/S = oligoamnios
How is stage II labor arrest treated?
Stage III should only be 2-3 hours. If prolonged... Try oxytocin. If oxytocin fails, check baby's station. Negative station --> C/section Positive station --> use Forceps or Vacuum to pull baby out.
How is stage III labor arrest treated?
Stage III should only be 30 minutes. If prolonged... 1. Uterine massage 2. Oxytocin 3. Manual extraction
How do you collect a GBS culture?
Swab the lower vagina and rectum (through the anal sphincter).
Treatment for aneuploidy
Termination
What is the Gold Standard for assessing fetal position?
Ultrasound Leopold maneuver is not sensitive nor accurate (pictured).
If LMP is unsure, what else can you use to date the EDC?
Ultrasound via crown-rump length
Naegele's Rule
add 7 days to LMP, subtract 3 months, add 1 year
Transverse (breech)
baby is in the transverse plane MC position to cause umbilical cord prolapse.
Stage 3 of labor and delivery
fetus --> placental delivery < 30 minutes
MCC of preterm labor
idiopathic
Longitudinal breech birth
longitudinal = alignment w/ mom breech = head is not first
What are the fetal risks in a mom with GDM?
macrosomnia shoulder dystocia Erb's palsy respiratory distress syndrome neonatal hypoglycemia
Quad Screen
maternal serum biochemical levels in the second trimester including: - human chorionic gonadotropin (hCG) - alpha-fetoprotein (AFP) - estriol - inhibin A
pPROM vs PROM vs ROM
pPROM is rupture of membranes *in preterm (< 37 wks)* pregnancy WITHOUT contractions. PROM is when rupture of membranes occurs *in term* pregnancy WITHOUT contractions. ROM is rupture of membranes *at term* WITH contractions.
Which anti-epileptics are teratogens? Which are ok?
phenytoin, carbamazepine, valproic acid *Use the "L" drugs. Leviteracitam or Lamotrigine.* Phenobarbital is safe in pregnancy if mom is seizing.
When should you follow up with a pregnant patient?
q4 wks to 28 wks q2 wks to 36 wks q1 wks to delivery
What is fetal station?
relation of the presenting part of the fetus to the maternal ischial spines, measures the degree of descent of the fetus. A negative station indicates fetal head is in uterus. A positive station indicates fetal head is in the vagina. -5 to + 5
Stage 1 of labor and delivery
starts when the muscles of the uterus contract and ends when the cervix is fully enlarged (about 10 cm) *latent phase*: 0 cm dilation --> 6 cm *active phase*: 6 cm --> 10 cm up to 20 hrs for nulliparous up to 14 hours for multi