Obstetrics Pearls Key points for your Board Review

• Labor and delivery terms: dilation of cervical os (up to 10cm), cervical effacement (up to 100%), station (location of presenting part relative to ischial spines; spines = 0; range = -2cm above spines to +2cm below spines)

• 4 stages of delivery: 1) 1st stage: regular uterine contractions to full cervical dilation; 2) 2nd stage: full dilation to delivery of infant; 3) 3rd stage: delivery of infant to delivery of placenta; 4) 4th stage: after delivery, repair of tears/hemorrhage management

• Late decelerations on fetal heart monitoring = uteroplacental insufficiency

• Late decelerations management: position mother in left lateral decubitus, administer oxygen, stop oxytocin

• Provider’s role in 3rd stage of delivery: suction, clamp/cut cord, keep infant warm, examine placenta/cord for retained products

• APGAR scores assessed at 1 and 5 minutes: Color, Heart rate, Respiration, Reflex response, Muscle tone (max score 2 per category)

• Dystocia (abnormal labor) management: plan for cesarean section, administer oxytocin, use forceps/vacuum

• Nuchal cord management: prevent cord compression (reduction, clamp/cut cord with rapid delivery)

• Cord prolapse management: elevate the presenting part to prevent cord compression; immediate cesarean section

• Shoulder dystocia management: HELPER (Help from consultants, Episiotomy, Legs flexed via McRoberts, Pressure suprapubically, Enter vagina via Rubin’s or Wood’s maneuver, Remove posterior arm)

• Postpartum hemorrhage caused by: uterine atony (most common), lacerations, retained products of conception, uterine inversion

• Uterine atony management: uterine massage, oxytocin, IV fluids

• Postpartum blues occurs in 50% of women; postpartum depression occurs in up to 13% of women during the first year

• Uterine rupture: fetal distress with palpation of fetal parts; diagnose with ultrasound; requires emergency cesarean section

• Endometritis: septic postpartum patient (day 2 or 3) with abdominal pain +/- foul-smelling lochia

• Mastitis/breast abscess: antibiotics, continue breastfeeding/pumping

• Abruptio placentae: most common cause of third trimester vaginal bleeding; two types: 1) concealed (not seen on ultrasound, no vaginal bleeding); or 2) apparent (seen on ultrasound, painful vaginal bleeding); diagnose with fetal stress testing

• Placenta previa: painless vaginal bleeding; diagnose with ultrasound, do not do pelvic exam

• Placenta previa seen in <20weeks gestation: 50% resolve and move away from os

• Tocolytics like magnesium sulfate and terbutaline should be used in preterm labor

• Hypertension in pregnancy: methyldopa or labetalol; beware of preeclampsia/eclampsia

• Hypertension + proteinuria + >20wk = preeclampsia (edema not necessary)

• Preeclampsia/eclampsia can occur up to 6weeks postpartum

• Preeclampsia/eclampsia treatment: delivery, magnesium, hydralazine/labetalol, steroids (if <36weeks)

• HELLP (Hemolysis, Elevated Liver enzymes, Low Platelets) treatment: delivery, blood pressure control, steroids (if <36weeks)

• Give RhoGAM if any question of baby’s blood entering Rh (-) mom’s circulation

• First trimester vaginal bleeding: 1) ultrasound to confirm intrauterine pregnancy; 2) follow serial beta-hCG; 3) determine Rh status of mother

• Beta-hCG normally doubles every 48 hours in first trimester

• Discriminatory zone: at beta-hCG 1500mU/mL, should see intrauterine pregnancy on transvaginal ultrasound

• 95% ectopic pregnancies occur in fallopian tube

• Ectopic risk factors: previous ectopic, pelvic inflammatory disease, history of tubal/abdominal surgery, intrauterine device, fertility treatment

• Ectopic management: methotrexate (if early, stable); surgery