Emergency Medicine EOR: Obstetrics and Gynecology (Smarty PANCE)

What is the first step in evaluating amenorrhea in a reproductive-age female?

Rule out pregnancy with urine or serum β-hCG before any further workup

What are the two categories of amenorrhea and their definitions?

Primary: absence of menses by age 15 with secondary sex characteristics (or age 13 without); Secondary: absence of menses for >3 months in previously menstruating female

What is the most common cause of secondary amenorrhea?

Pregnancy - always check β-hCG first

What lab panel is ordered after negative β-hCG in secondary amenorrhea workup?

TSH, prolactin, FSH, LH; if virilization suspected add testosterone and DHEA-S

How do you differentiate outflow tract obstruction from ovarian failure in amenorrhea?

Progesterone challenge test: withdrawal bleed = anovulation (intact outflow tract); no bleed = either outflow obstruction or ovarian failure; check FSH to differentiate

Elevated FSH + LH with low estrogen in amenorrhea indicates what diagnosis?

Primary ovarian insufficiency (hypergonadotropic hypogonadism); FSH >40 mIU/mL is diagnostic

Low FSH + LH with low estrogen in amenorrhea indicates what diagnosis?

Hypothalamic or pituitary dysfunction (hypogonadotropic hypogonadism); causes include stress, extreme exercise, anorexia, or pituitary tumor

What are classic features of Asherman syndrome and how is it diagnosed?

Intrauterine adhesions (synechiae) after D&C or uterine surgery; no withdrawal bleed on progesterone challenge; diagnosed by hysteroscopy (gold standard)

What is the pathognomonic finding of Kallmann syndrome causing amenorrhea?

Hypogonadotropic hypogonadism + anosmia (absent sense of smell) due to GnRH neuron migration failure

What are the diagnostic criteria for PCOS (Rotterdam criteria) and its relationship to amenorrhea?

Two of three: oligo/anovulation, clinical/biochemical hyperandrogenism, polycystic ovaries on ultrasound; most common cause of secondary amenorrhea after pregnancy

What is the minimum criteria required to diagnose PID?

Cervical motion tenderness (CMT), uterine tenderness, OR adnexal tenderness in a sexually active female with no other explanation

What organisms most commonly cause PID?

Neisseria gonorrhoeae and Chlamydia trachomatis (most common); also polymicrobial (Gardnerella, anaerobes, E. coli)

What is the outpatient treatment regimen for uncomplicated PID?

Ceftriaxone 500 mg IM x1 + Doxycycline 100 mg PO BID x14 days + Metronidazole 500 mg PO BID x14 days

What are the indications for inpatient admission and IV antibiotics in PID?

Tubo-ovarian abscess (TOA), failure of outpatient therapy, unable to tolerate PO, pregnancy, surgical emergency cannot be excluded

What is the inpatient IV treatment regimen for PID?

Cefoxitin 2g IV q6h (or cefotetan) + Doxycycline 100 mg IV/PO q12h; alternative: Clindamycin + Gentamicin

What is the most serious complication of PID and how does it present on imaging?

Tubo-ovarian abscess (TOA); pelvic ultrasound shows complex adnexal mass with internal echoes; CT confirms if ultrasound equivocal

What long-term complications arise from PID (use mnemonic)?

EPIC: Ectopic pregnancy risk (6-10x increased), Pelvic pain (chronic), Infertility (from tubal scarring), Chronic adhesions

What is Fitz-Hugh-Curtis syndrome and what causes it?

Perihepatitis (violin-string adhesions over liver capsule) from ascending PID infection (Chlamydia or Gonorrhea); presents as RUQ pain in a young sexually active female

What is the gold standard diagnostic test for PID when diagnosis is uncertain?

Laparoscopy (direct visualization); not required for clinical diagnosis but definitive

What is the PALM-COEIN classification system used for?

Classification of abnormal uterine bleeding (AUB) etiologies: PALM = structural (Polyp, Adenomyosis, Leiomyoma, Malignancy); COEIN = non-structural (Coagulopathy, Ovulatory, Endometrial, Iatrogenic, Not classified)

What is the most common cause of abnormal uterine bleeding in reproductive-age women?

Anovulatory cycles (ovulatory dysfunction) - most common non-structural cause

What is the most common cause of postmenopausal bleeding and what must always be ruled out?

Atrophic vaginitis/endometritis (most common); but endometrial carcinoma must be excluded - endometrial biopsy or transvaginal ultrasound required

What endometrial stripe thickness on transvaginal ultrasound warrants biopsy in a postmenopausal woman?

>4 mm stripe thickness requires endometrial biopsy to rule out carcinoma

What is the first-line medical treatment for anovulatory AUB?

Combined oral contraceptive pills (OCPs) for cycle regulation; progesterone alone if estrogen is contraindicated

What is the acute management of heavy AUB with hemodynamic stability?

High-dose estrogen (conjugated estrogen 25 mg IV q4-6h) or high-dose combined OCP (monophasic pill 3-4x/day) to stabilize

What is the surgical treatment of last resort for refractory AUB in a patient who desires no future fertility?

Hysterectomy (definitive); endometrial ablation is a less invasive alternative for women who desire no future fertility

When should endometrial biopsy be performed in AUB workup?

Women >45 years, < 45 with risk factors (obesity, PCOS, unopposed estrogen, family history), or failed medical therapy

What is the difference between primary and secondary dysmenorrhea?

Primary: painful menses without identifiable pathology (excess prostaglandins); Secondary: painful menses WITH underlying pathology (endometriosis, fibroids, adenomyosis, PID)

What is the first-line treatment for primary dysmenorrhea?

NSAIDs (e.g., ibuprofen, naproxen) started 1-2 days before menses onset; COX-1/COX-2 inhibition reduces prostaglandin synthesis

What is the second-line treatment for primary dysmenorrhea if NSAIDs fail?

Combined oral contraceptive pills (OCPs) to suppress ovulation and reduce endometrial prostaglandins

What is the most common cause of secondary dysmenorrhea?

Endometriosis

What feature of pain distinguishes secondary from primary dysmenorrhea?

Secondary dysmenorrhea often begins BEFORE menses, persists AFTER menses ends, and worsens progressively over years

What is Mittelschmerz and when does it occur?

Mid-cycle pelvic pain from follicular rupture at ovulation (day 14); unilateral, self-limited, no treatment needed

What is the classic triad of ectopic pregnancy?

Amenorrhea, vaginal bleeding, and unilateral pelvic/adnexal pain

What is the gold standard diagnostic approach for suspected ectopic pregnancy?

Transvaginal ultrasound (TVUS) + quantitative serum β-hCG; ectopic suggested when β-hCG >1500-2000 mIU/mL (discriminatory zone) with no intrauterine pregnancy on TVUS

What β-hCG doubling pattern suggests ectopic vs. normal intrauterine pregnancy?

Normal IUP: β-hCG doubles every 48-72 hours; Ectopic or failing pregnancy: β-hCG rises < 53% in 48 hours or plateaus

What are the criteria for methotrexate treatment of ectopic pregnancy?

Hemodynamically stable, unruptured ectopic, β-hCG < 5000 mIU/mL (relative), no fetal cardiac activity, able to follow up; contraindicated if breastfeeding, immunocompromised, liver/renal disease

What are the signs of a ruptured ectopic pregnancy requiring emergent surgery?

Hemodynamic instability (hypotension, tachycardia), peritoneal signs, shoulder pain (diaphragmatic irritation from hemoperitoneum), syncopal episodes

What is the most common site for ectopic implantation?

Ampulla of the fallopian tube (~70% of ectopics)

What risk factors predispose to ectopic pregnancy (mnemonic PETS)?

Prior ectopic, Endometriosis/PID/STI history, Tubal surgery or ligation, Smoking/IUD/ART use

What is the classic presentation of placental abruption?

Painful vaginal bleeding in the third trimester; uterus is rigid/tender ("board-like"), often with fetal distress; associated with hypertension and cocaine use

What differentiates placental abruption from placenta previa on presentation?

Abruption: PAINFUL bleeding, tender rigid uterus, fetal distress; Previa: PAINLESS bleeding, soft non-tender uterus

What is the most common cause of placental abruption?

Hypertension (chronic or gestational/preeclampsia) is the #1 risk factor; others include trauma, cocaine use, prior abruption, smoking

What lab findings suggest consumptive coagulopathy (DIC) in placental abruption?

Elevated PT/PTT, low fibrinogen (< 200 mg/dL is concerning; <150 mg/dL diagnostic), thrombocytopenia, elevated D-dimer

What is the management of placental abruption?

Stabilize mother (IV access, type & cross, fluids/blood products); continuous fetal monitoring; delivery is definitive - vaginal if stable and fetal status reassuring, C-section if fetal distress or maternal hemorrhage

What is Couvelaire uterus and in what condition does it occur?

Extravasation of blood into uterine myometrium causing a purple, woody uterus; occurs in severe placental abruption; may require hysterectomy

What is the classic triad of endometriosis?

Dysmenorrhea, dyspareunia (painful intercourse), and infertility

What is the gold standard for diagnosing endometriosis?

Surgical laparoscopy with biopsy showing ectopic endometrial glands and stroma

What are the classic findings of endometriosis on laparoscopy?

"Powder-burn" or "gunshot" lesions (blue-black spots), chocolate cysts (endometriomas) in ovaries, adhesions

What is the first-line treatment for endometriosis-related pain?

NSAIDs + combined oral contraceptive pills (OCPs); or progestins (norethindrone, DMPA)

What is the second-line hormonal treatment for endometriosis if OCPs fail?

GnRH agonists (leuprolide) causing medical menopause; add-back therapy with low-dose estrogen/progestin to prevent bone loss

What CA-125 finding is associated with endometriosis and what is its limitation?

CA-125 may be elevated but is NOT diagnostic (low sensitivity/specificity); used to monitor treatment response, not for diagnosis

What is the definitive treatment for endometriosis?

Surgical excision/ablation of lesions; hysterectomy + bilateral salpingo-oophorectomy for severe, refractory cases

What complication of endometriosis can mimic ovarian malignancy on ultrasound?

Endometrioma ("chocolate cyst") - homogeneous low-level echoes on ultrasound ("ground glass" appearance)

What is the hallmark presentation of placenta previa?

Painless, bright red vaginal bleeding in the third trimester (after 20 weeks); uterus is soft and non-tender

What is the diagnostic test of choice for placenta previa?

Transvaginal ultrasound (TVUS) - safe and superior to transabdominal US for placental localization

What is the absolute contraindication in suspected placenta previa?

Digital vaginal examination - can precipitate massive hemorrhage

What are the types of placenta previa?

Complete: placenta covers the entire os; Partial: covers part of os; Marginal: placental edge within 2 cm of os; Low-lying: within 2-3.5 cm of os

What is the management of stable placenta previa at < 37 weeks?

Pelvic rest, hospitalization if bleeding, corticosteroids if 24-34 weeks, magnesium if < 32 weeks for fetal neuroprotection; delivery at 36-37 weeks

What delivery method is required for complete placenta previa?

Cesarean section (C-section) - vaginal delivery is contraindicated

What placental complication is associated with prior uterine scar and placenta previa?

Placenta accreta spectrum (accreta, increta, percreta) - abnormal placental invasion; risk of massive hemorrhage and hysterectomy at delivery

What are the three categories of fetal heart rate decelerations and their significance?

Early (head compression, benign, mirrors contractions); Variable (cord compression, concerning if severe/prolonged); Late (uteroplacental insufficiency, ALWAYS non-reassuring)

What is the definition of fetal distress on cardiotocography?

Non-reassuring fetal heart rate pattern: late decelerations, severe variable decelerations, prolonged deceleration >2 min, absent variability, or sinusoidal pattern

What is the immediate management of non-reassuring fetal heart rate patterns?

LOOP: Left lateral decubitus position, Oxygen (10 L/min by face mask), IV fluid bolus, discontinue Pitocin (oxytocin); if no improvement → emergent delivery

What is the normal fetal heart rate range?

110-160 bpm

What findings on fetal scalp pH indicate fetal acidosis requiring delivery?

pH < 7.20 = acidosis, immediate delivery required; pH 7.20-7.25 = borderline, repeat in 30 minutes; pH >7.25 = reassuring

What is a sinusoidal fetal heart rate pattern and what does it suggest?

Smooth, sine wave-like pattern with no beat-to-beat variability; associated with severe fetal anemia (Rh isoimmunization, vasa previa) - requires immediate delivery

What is the definition of premature rupture of membranes (PROM)?

Rupture of membranes before onset of labor; PPROM = PROM before 37 weeks gestation

How is PROM diagnosed clinically?

Pooling of fluid in posterior vaginal vault, ferning on microscopy (dried fluid on slide), positive nitrazine test (pH >6.5, turns blue); ultrasound shows oligohydramnios

What is the most sensitive/specific test for PROM?

AmniSure (PAMG-1) or ActimPROM (IGFBP-1) immunoassay - more accurate than ferning or nitrazine

What is the management of PPROM at 34-36 6/7 weeks?

Delivery (induction or C-section based on obstetric indications)

What is the management of PPROM at < 34 weeks with no infection?

Expectant management with hospitalization, antibiotics (latency antibiotics: azithromycin + ampicillin), corticosteroids (betamethasone) for fetal lung maturity, GBS prophylaxis

What antibiotic regimen is used for latency in PPROM?

Azithromycin 1g PO x1 + Ampicillin IV x48h then Amoxicillin PO x5 days (Erythromycin if azithromycin unavailable); avoid amoxicillin-clavulanate (↑ NEC risk)

What is chorioamnionitis and what are its diagnostic criteria?

Intra-amniotic infection; diagnosed by maternal fever >38°C AND one of: maternal tachycardia, fetal tachycardia, uterine tenderness, purulent amniotic fluid, maternal leukocytosis

What is the treatment of chorioamnionitis?

Broad-spectrum IV antibiotics (ampicillin + gentamicin ± clindamycin) AND delivery; antibiotics continued until delivery and postpartum

What is Naegele's rule for calculating estimated due date?

EDD = LMP + 9 months + 7 days (or LMP - 3 months + 7 days + 1 year)

What are the landmarks for gestational age assessment by fundal height?

12 weeks: pubic symphysis; 20 weeks: umbilicus; fundal height in cm ≈ gestational age in weeks (±2 cm) from 20-36 weeks

What is the most accurate method for determining gestational age?

Ultrasound crown-rump length (CRL) in first trimester (before 12 weeks) - most accurate within ±5-7 days

What prenatal labs are obtained at the first OB visit?

Blood type/Rh factor, antibody screen, CBC, rubella immunity, hepatitis B surface antigen, HIV, RPR/VDRL (syphilis), urine culture, Pap smear if due, gonorrhea/chlamydia

When is fetal viability generally established?

23-24 weeks gestation

What are the recommended prenatal screening tests by trimester?

1st trimester: cell-free fetal DNA (NIPT), nuchal translucency + PAPP-A + β-hCG (first trimester screen); 2nd trimester: quad screen (AFP, hCG, estriol, inhibin A), anatomy ultrasound 18-20 weeks; 24-28 weeks: 1-hour glucose challenge test

What defines a spontaneous abortion (miscarriage)?

Loss of pregnancy before 20 weeks gestation; most common cause is chromosomal abnormality (50-60%)

What are the types of spontaneous abortion and their key features?

Threatened: bleeding, closed cervix, viable pregnancy; Inevitable: bleeding, OPEN cervix, no tissue passed; Incomplete: tissue partially passed, open cervix; Complete: all tissue passed, closed cervix; Missed: fetal demise without expulsion

What is the management of a threatened abortion?

Pelvic rest, supportive care; if viable IUP on ultrasound, expectant management; progesterone supplementation if progesterone deficiency suspected

What is the management of an inevitable or incomplete abortion?

Uterine evacuation: medical (misoprostol) or surgical (suction curettage/D&C); Rh-negative patients receive RhoGAM

What is the most common cause of recurrent pregnancy loss (≥2 losses)?

Chromosomal abnormalities (most common); other causes: antiphospholipid syndrome, uterine anomalies, thrombophilias, endocrine disorders

What is the workup for recurrent pregnancy loss?

Parental karyotype, antiphospholipid antibodies (lupus anticoagulant, anticardiolipin, anti-β2 glycoprotein), uterine anatomy (hysteroscopy/HSG), thrombophilia panel

What anti-D immunoglobulin (RhoGAM) indication exists in pregnancy loss?

All Rh-negative, unsensitized patients with spontaneous abortion, threatened abortion >10-12 weeks, or any pregnancy loss should receive RhoGAM

What is a septic abortion and how is it managed?

Infected uterine contents after abortion (spontaneous or induced); fever, purulent/foul-smelling discharge, uterine tenderness; management: IV broad-spectrum antibiotics + urgent uterine evacuation

What is the classic presentation of mastitis and who does it most commonly affect?

Lactating women (most common 2-4 weeks postpartum); presents with unilateral breast erythema, warmth, swelling, tenderness, and systemic symptoms (fever, myalgia, flu-like illness)

What is the most common causative organism of mastitis?

Staphylococcus aureus (including MRSA); enters through cracked/fissured nipples

What is the first-line treatment for mastitis?

Continue breastfeeding/pumping (do NOT stop), dicloxacillin 500 mg QID x10-14 days (or cephalexin); if MRSA suspected: TMP-SMX or clindamycin

How do you distinguish a breast abscess from mastitis?

Breast abscess: fluctuant mass, fails to respond to antibiotics in 48-72h; ultrasound shows fluid collection; treatment requires incision and drainage (I&D) + antibiotics

What is the treatment of a breast abscess?

Ultrasound-guided needle aspiration (preferred if < 3 cm) OR surgical incision and drainage (I&D) + antibiotics covering S. aureus; continue breastfeeding if possible

When should mastitis NOT be treated with antibiotics alone?

If fluctuance is present, no improvement after 48-72h of antibiotics, or ultrasound shows abscess - requires drainage

What systemic signs differentiate mastitis from a breast abscess?

Both have fever; abscess more often has localized fluctuant mass, point tenderness, and fails antibiotic monotherapy

What are the most common causes of vaginal discharge by category?

Physiologic (clear, odorless); Bacterial vaginosis (BV): thin gray-white, fishy odor; Trichomoniasis: frothy yellow-green; Candidiasis (yeast): thick white "cottage cheese," no odor

What are the Amsel criteria for diagnosing bacterial vaginosis (BV)?

3 of 4: thin homogeneous gray-white discharge, clue cells on wet prep, vaginal pH >4.5, positive whiff test (fishy odor with KOH)

What is the treatment for bacterial vaginosis (BV)?

Metronidazole 500 mg PO BID x7 days OR metronidazole gel 0.75% intravaginally x5 days OR clindamycin cream 2% intravaginally x7 days

What microscopic finding is pathognomonic for bacterial vaginosis?

Clue cells - vaginal epithelial cells studded with bacteria, obscuring cell borders on wet prep