OBGYN 1 Flashcards
What do the GP numbers stand for.
E.g. G3P1234
G = total pregnancies P1 = term pregnancies P2 = preterm pregnancies P3 = abortion/miscarriage/molar pregnancies/etc P4 = living children
What are the structural causes of abnormal uterine bleeding
PALM
• P = polyp
o Vascular, glandular, fibromusclar, connective tissue
• A = adenomyosis
o Endometrial cells growing within the myometrium
• L = leiomyoma (fibroid)
o Benign neoplastic proliferation of smooth muscle arising from myometrium
• M = malignancy and hyperplasia
What are the nonstructural causes of abnormal uterine bleeding
COEIN • C = coagulopathy • O = ovulatory dysfunction • E = endometrial • I = iatrogenic • N = not yet classified
Definition of labor
Regular contractions + cervical changes
What are the 2 hormones of normal labor
Oxytocin and prostaglandin
Effects of oxytocin
• Released by the posterior pituitary and responsible for uterine contractions, let-down reflex in a breastfeeding mother, and bonding behavior
Effects of prostaglandin
• Released in tissue throughout the body and responsible for smooth muscle contraction of the uterus and the biophysical changes associated with ripening of the cervix
What is the 1st stage of labor
• From the onset of labor (closed cervix) to complete dilation of cervix
What are the 2 phases in the 1st stage of labor
- Latent phase (closed cervix to 6 cm)
- Active phase (6 cm to complete dilation)
What is the 2nd stage of labor
- Pushing and delivery of baby
- Complete dilation of the cervix
- Often accompanied by an urge to bear down
What is the 3rd stage of labor
• Placental delivery • Signs of separation - Lengthening of the cord - Bleeding - Uterus becomes firm and globular • Delivery of placenta with gentle cord traction and counter pressure on uterus above symphysis pubis
What is the fourth stage of labor
- The first hour immediately after delivery of infant
- Close observation of vital signs
- Monitor fundus for firmness
- Monitor perineum for bleeding/ lochia
Describe fetal heart rate decelerations
♣ V = variable decelerations . . . C = cord compression
♣ E = early decelerations . . . H = head compression
♣ A = acceleration . . . O = oxygenation
♣ L = late decelerations . . . P = placental insufficiency
Normal blood loss for vaginal birth
< 500 cc
>500 = hemorrhage
Normal fetal heart rate baseline
110-160
Normal frequency of contractions
5 or fewer contractions in 10 minutes, averaged over a 30 minute window (Q2 minutes)
What are 3 broad categories of dystocia
Dystocia = difficult labor
♣ Power - are the contractions strong enough?
♣ Passenger – what is the position of the fetus?
♣ Pelvis - what are the pelvic diameters?
Common causes of labor dystocia
♣ Abnormal fetal position ♣ Congenital Anomalies ♣ Hypotonic uterine contraction ♣ Excessive Conduction Anesthesia ♣ Cephalopelvic disproportion (CPD) ♣ Macrosomia (>4500 gm)
What are the 4 components we care about in fetal heart rate
- baseline
- variability
- accelerations
- decelerations
What does FHR variability tell you
• It is an indication of central nervous system development and oxygenation.
What is normal FHR variability
Moderate = 6-25
What does absent FHR variability indicate
o Can be associated with sleep cycles, medication effects, fetal acidosis
What does marked FHR variability indicate
> 25 bpm
o Mild hypoxia, fetal activity, medications
What does a sinusoidal FHR pattern mean
• Shows a very regular pattern
o Fetal anemia, fetal bleeding, fetal isoimmunization, TTTS, cord occlusion, CNS malformations
o Requires immediate delivery
What do FHR accelerations indicate
• Indicates normal fetal acid-base status. Fetus is well-oxygenated
What does FHR early decelerations look like and indicate
o Nadir (largest point of trough) simultaneous with peak of contraction.
o Often vagal response from head compression
What does FHR late decelerations look like and indicate
o Nadir after peak of contraction.
o Placental insufficiency. Excessive uterine contractions, maternal hypotension, maternal hypoxemia, reduced maternal placental exchange as in hypertensive disorders, diabetes, IUGR abruption
What doe FHR variable decelerations look like and indicate
o Abrupt onset.
o <30 seconds from onset to beginning of nadir lasting > 15 seconds but < 2 minutes, depth >15 bpm
o Cord compression, movement in the premature fetus
Describe Non-stress test (NST)
♣ Gather all previous data and determine if the FHR is REACTIVE or NON-REACTIVE
♣ A Reactive NST
• An increase of 15 BPM above baseline for 15 second duration (from baseline to baseline) twice in a 20 minute period.
• Only 65% of fetuses at 28 weeks are reactive by this criteria.
• By 34 weeks 95% of fetuses are reactive.
Describe components of category I FHR (baseline, variability, decelerations, acceleration)
Cat I = good! o Baseline rate: 110-160 beats per minute (bpm) o Baseline FHR variability: moderate o Late or variable decelerations: absent o Early decelerations: present or absent o Accelerations: present or absent
Describe components of Category III FHR (baseline, variability, deceleration, acceleration)
Cat III = bad! o Absent baseline FHR variability and any of the following: ♣ Recurrent late decelerations ♣ Recurrent variable decelerations ♣ Bradycardia o Sinusoidal pattern
How does HPV cause cancer? (activation of oncogenes)
E6 increases degradation of p53
E7 inactivates the RB gene, which leads to increased synthesis of he intracellular protein p16
What are the cardinal movements of labor
Descent –> flexion –> internal rotation –> extension –> external rotation –> expulsion
When during pregnancy do you give RhoGAM to an Rh neg mom
28 weeks
What is the range that is considered term pregnancy
37-42 weeks
Why is magnesium given in pregnant patients
Seizure prophylaxis for pre-eclampsia
Signs of magnesium toxicity
Loss of deep tendon reflexes, HA, vision changes, SOB/chest pain (pulmonary edema), RUQ pain
Most accurate clinical indicator of resolution of pre-ecclampsia
Diuresis (good urine output)
What are the 3 P’s to think about when there is arrest of labor
- Power (contractions)
- Passenger (
- Pelvis (pelvis is too small or baby is too large)
What is tachysystole
Uterine contractions > 5/10 min (> every 2 min)
Intervention for tachysystole
Decrease or stop oxcytocin, or administer beta-mimetic agent (e.g. Terbutaline) for uterine relaxation
Intervention for low BP following epidural or spinal
IV fluid bolus, or administer vasopressor agent such as ephedrine
Intervention for umbilical prolapse (cord through cervix)
Elevate presenting part and emergency C-section
Intervention for placental abruption
Support BP, stabilize patient, consider C-section if progressive
Intervention for uterine rupture
Emergency C-section
Definition of arrest of active labor
• No progress in the active phase of labor (>6 cm) with ruptured membranes for 4 hours without adequate contractions, or 6 hours of inadequate contractions
Treatment of repetitive deep variable decelerations
Variable decel = cord compression
Tx = amnioinfusion to help alleviate cord compression
Tx of repetitive late decelerations after epidural
Epidural can lead to hypotension in mom –> placental insufficiency
Tx = IV fluids, then vasopressor (e.g. Ephedrine - causes vasoconstriction of the peripheral vasculature but spares the uterine arteries)
What are the 4 signs of placental separation
(1) Gush of blood
(2) Lengthening of cord
(3) Firm and globular shape of uterus
(4) Uterus rises up to anterior abd wall
