NBME OBGYN Form 5 - Answers & Explanations

Updated: Nov 16, 2019

Authors: Luke Carlson

Editor: Jordan Abrams

1) Hemorrhagic shock

• Active, prolonged vaginal bleeding

2) Endometriosis

• Ectopic implantation of endometrial glands

• Clinical features: dysmenorrhea, dyspareunia, dyschezia, infertility

3) Dicloxacillin

• Lactational mastitis – tenderness of unilateral breast in lactating patient

• Clinical Features: erythema, tenderness, fever, fissures of nipple

• Pathogenesis – skin flora (eg, Staphylococcus aureus) → clogged, inflamed milk ducts

• Tx: frequent breastfeeding, antibiotics (cover for MSSA – penicillin, penicillinase-resistant)

4) Dehiscence

• Disruption or breakdown of a wound, serosanguineous drainage

• Diabetes mellitus → delayed wound healing → ↑ risk of dehiscence

5) ↓ACTH, ↓TSH, ↓LH, ↓FSH, ↓GH

• Sheehan syndrome: obstetric hemorrhage → hypotension → postpartum pituitary infarction

• Clinical features:

• Anorexia, weight loss, hypotension (↓ ACTH)

• Fatigue, dry skin, constipation, cold intolerance (↓ TSH)

• Amenorrhea, hot flashes, vaginal atrophy (↓ FSH, LH)

• ↓ lean body mass (↓ GH)

• Lactation failure (↓ prolactin)

6) Kell typing of the father’s blood

• Kell antigen system – group of antigens found on RBC surface; help determine blood type

• Anti-Kell antibodies (IgG) – transplacental hemolytic disease of newborn

• Mother tested positive for anti-K, therefore father needs to be tested to determine the risk of fetal K antigen

7) Hepatitis B

• Recommended vaccinations during pregnancy for high-risk patients (eg, multiple STDs)

• Hepatitis B, Hepatitis A, Pneumococcus, Haemophilus influenzae, Meningococcus,

Varicella-zoster immunoglobulin

• ⊖ Hepatitis B surface antigen assay = no Hep B exposure

• Live-attenuated vaccine are contraindicated in pregnancy (eg, MMR, live attenuated influenza, varicella)

8) Influenza virus

• Yearly routine health maintenance examination with all childhood vaccinations no high-risk behavior

9) Ectopic pregnancy

• ⊕ pregnancy test with adnexal mass, vaginal spotting and unilateral abdominal pain

10) Gonadal dysgenesis 45,X (Turner syndrome)

• Primary amenorrhea due to small, non-functioning ovaries (streak ovaries)

• Typical short stature, webbed neck, “shield chest” ( minimal breast development - tanner 3)

11) Vaginal miconazole

• Candida vaginitis tx: antifungal (eg, fluconazole)

• Mild erythema and excoriation (pruritus), no vaginal bleeding or discharge

• Microscopy reveals pseudohyphae

12) Urinary retention

• Inefficient detrusor muscle activity → hypotonic bladder (common postoperative complication)

• Soft symmetric mass extending 25cm above symphysis = distended bladder

• ↑ BUN & creatinine

13) Induction of labor

• Intrauterine fetal demise = fetal death ≥ 20 weeks

• Absence of fetal cardiac activity on US

• Management:

• 20-23 weeks: Dilation and evacuation OR vaginal delivery

• 24 weeks or greater: vaginal delivery

• Complication: coagulopathy after several weeks of fetal retention

• Hb 11g/dL, Hematocrit 32%, Platelets 90,000/mm3

• Missed abortion: no vaginal bleeding, closed cervical os, no fetal cardiac activity

14) Fibroadenoma

• Solitary, well-circumscribed, mobile mass

• Most common cause of breast mass in an adolescent (versus a breast cyst, which is most common after age 30)

• Size & tenderness fluctuate with estrogen exposure → cyclic premenstrual tenderness

15) Herpes simplex virus

• Small, painful vesicles or ulcers on erythematous base (can coalesce), mild lymphadenopathy

• Urine contact on ulcers → Pain with urination

• Patient's systemic symptoms indicate this is a primary HSV infection

16) Thrombus within the pulmonary arteries

• Pulmonary embolism (possibly pulmonary saddle thrombus) → pleuritic chest pain, shortness of breath, hypotension, ↓ SaO₂

17) HIV antibody test

• Recent multiple sexual partners, current STI (gonorrhea or Chlamydia)

• Should also screen for HIV (USPSTF recommends HIV antibody screen 1 time for adults 15-65)

18) Breast

• Adenocarcinoma – glandular (milk ducts or lobules)

• Lymph node drainage:

• Axillary lymph node – breast

• Right supraclavicular lymph node – mediastinum, lung, esophagus

• Left supraclavicular lymph node – thorax, abdomen via thoracic duct

19) Cesarean delivery

• Pregnancy in achondroplasia is considered high risk – cesarean section is usual mode of delivery

• Cephalopelvic disproportion

20) Maternal intramuscular administration of Rho (D) immune globulin now

• RhoD immunoglobulin normally given at 28 weeks AND within 72 hours of any procedure in which there is a possibility of feto-maternal blood mixing (eg, after delivery)

• Other indications for RhoD immunoglobulin administration:amniocentesis, chorionic villus sampling, and external cephalic version

21) Increasing catecholamine

• Cocaine → presynaptic norepinephrine (NE) & dopamine (DA) release, and inhibition of NE, DA and serotonin (5-HT) reuptake

22) Undiagnosed maternal diabetes mellitus

• Diabetes mellitus → excessive weight gain, polyhydramnios, fetal macrosomia

23) Chorioamnionitis

• Prolonged rupture of membranes (>18 hours), prolonged labor, maternal fever, GBS +, leukocytosis, fetal tachycardia

24) Depot medroxyprogesterone

• Depot medroxyprogesterone has no risk of DVT (administered IM every 3 months)

• DDx: acute pelvic infection is an absolute contraindication for placement of IUD, patient would like to have children in the future (tubal ligation not appropriate), patient has trouble remembering (no OCPs or vaginal ring), as well as having DVT (OCP contraindicated)

25) Mature teratoma

• Unilateral, complex adnexal mass; echogenicity on U/S likely due to hair

26) Endometrial biopsy

• Endometrial biopsy is indicated for all women >45 with postmenopausal or abnormal uterine bleeding

27) T