Snapshot A 32-year-old G1P2 presents to labor and delivery with contractions. She has been having 1 painful contraction every 20 minutes for the past 2 hours and reports mild spotting on her underwear. A transabdominal ultrasound is performed followed by a pelvic exam. Her cervix is effaced 90% and dilated 5 cm. She is admitted for active labor. Introduction Overview involves spontaneous and regular contractions +/- rupture of membranes Labor true progressive effacement and dilation of uterine cervix resulting from contractions of uterus false Braxton Hicks contraction uterine contractions without effacement and dilation of cervix managed with reassurance and discharge preterm prior to 36 weeks and 6 days Epidemiology 85% of pregnant people undergo spontaneous labor and delivery between 37-42 weeks Presentation Symptoms that require hospital presentation contractions ≥ 4 every 20 minutes or ≥ 8 every 60 minutes rupture of membranes significant bleeding small amount of mucoid bleeding is normal in early labor ("bloody show") decrease in fetal movement Physical exam vital signs blood pressure (BP) heart rate (HR) respiratory rate (RR) temperature auscultation of fetal heart sounds determine fetal position Leopold maneuvers steps taken to palpate the uterus to assess fetal presentation and position vaginal exam to check rupture of membranes (ROM) cervical effacement and dilation fetal station (level of fetus relative to ischial spine) zero station is at the level of the ischial spine Admission for active labor cervial effacement ≥ 80% 4-5 cm dilation Imaging Transabdominal ultrasound indications determine fetal position rule out placenta previa and premature rupture of membranes (PROM) perform prior to digital exam Studies Serum labs complete blood count (CBC) blood type and screen rapid HIV testing hepatitis B syphillis group B streptococcus (GBS) Preterm Labor Definition uterine contractions ≥ 4 every 20 minutes or ≥ 8 every 60 minutes cervical dilation ≥ 3 cm Symptoms menstrual-like cramps low back ache discharge of mucous from vagina spotting contractions Physical exam digital cervical examination (after transabdominal ultrasound (US)) speculum exam (after digital exam) Imaging transabdominal US transvaginal US Studies fetal fibronectin testing rectovaginal GBS culture urine culture substance use testing sexually transmitted infection (STI) testing Management gestational ages 34 weeks to 36 weeks and 6 days delivery by induction if necessary penicillin if GBS culture is positive or unknown 32 weeks to 33 weeks and 6 days expectant management unless fetal lungs have reached maturity betamethasone penicillin if GBS culture is positive or unknown antimicrobials if no contractions 24 weeks to 31 weeks and 6 days expectant betamethasone penicillin if GBS culture is positive or unknown tocolytics with indomethacin magnesium sulfate < 24 weeks patient counseling expectant management or induction