Obstetrics & Gynecology USMLE Practice Questions

A. Embryonal rhabdomyosarcoma

This option implies sarcoma botryoides, which causes grape-like vaginal mass and bleeding, BUT this patient has a normal pelvic exam and no mass described.

B. Endometrial polyp

This option implies a structural lesion causing intermenstrual spotting, BUT adolescents rarely have polyps, and her exam is normal with a pattern typical of anovulation.

C. Decreased thyroxine production

This option implies hypothyroidism, which can cause menorrhagia, BUT she lacks weight gain, fatigue, cold intolerance, or growth delay; exam is unremarkable.

E. Inflammation of the endometrium

This option implies endometritis, which typically presents with pelvic pain, fever, and often postpartum/postabortal history, BUT she has none of these and normal exam.

F. Defective von Willebrand factor

This option implies von Willebrand disease, which causes mucosal bleeding, epistaxis, easy bruising, and often family history, BUT none of these are mentioned and bleeding is tied to cycle irregularity after menarche.

G. Excessive androgen production

This option implies PCOS or androgen-secreting tumor, which causes hirsutism, acne, obesity, or virilization, BUT she has normal exam and is underweight (20th percentile).

H. Uterine fibroid

This option implies leiomyoma, common in older reproductive-age women with enlarged, irregular uterus, BUT a 14-year-old with normal exam is very unlikely to have symptomatic fibroids.

A. Intraductal papilloma

This option implies a benign papillary lesion within lactiferous ducts, typically causing bloody nipple discharge, BUT this patient has a large deep mass with no nipple changes or discharge and stromal atypia, which is not typical for intraductal papilloma.

C. Paget disease of the breast

This option implies DCIS extending to the nipple epidermis, causing erythema, crusting, and ulceration of the nipple/areola, BUT this patient has no nipple skin changes and instead has a large, well-circumscribed mass with stromal papillary projections.

D. Fibroadenoma

This option implies a common benign fibroepithelial tumor in younger women (<35) with small, firm, mobile masses and bland stroma, BUT this patient is older with a large, rapidly enlarging mass and biopsy showing stromal hyperplasia/atypia, which is more consistent with phyllodes tumor.

E. Fibrocystic disease of the breast

This option implies diffuse, often bilateral, cyclically painful nodularity related to menses, BUT this patient has a single, large, painless, well-circumscribed mass and specific stromal papillary projections, not diffuse cystic changes.

F. Invasive ductal carcinoma

This option implies a malignant epithelial tumor often presenting as a hard, irregular, fixed mass with possible skin dimpling or nipple retraction, BUT this mass is smooth, polylobulated, non-tender, with stromal papillary projections and no overlying skin changes or lymphadenopathy, supporting a fibroepithelial tumor instead.

G. Invasive lobular carcinoma

This option implies a malignant tumor with discohesive cells (loss of E-cadherin) often presenting as a poorly defined thickening rather than a well-circumscribed mass, BUT this lesion is well-defined, polylobulated, and shows stromal papillary projections and atypia, features of a fibroepithelial tumor (phyllodes), not lobular carcinoma.

A. Polyhydramnios

This option implies excess amniotic fluid, often due to fetal swallowing problems or maternal diabetes, BUT postterm pregnancies more often have oligohydramnios, not polyhydramnios, and no swallowing issues are described.

B. Acute respiratory distress syndrome

This implies neonatal RDS from surfactant deficiency, typical in premature infants (<34 weeks), BUT this fetus is postterm, where lungs are mature; the respiratory risk is from meconium aspiration, not surfactant deficiency.

C. Caudal regression syndrome

This implies a severe fetal anomaly strongly associated with maternal pregestational diabetes, BUT the mother has no history of diabetes or hyperglycemia; obesity alone without diabetes is insufficient to predict this defect.

E. Placental abruption

This implies premature separation of the placenta with painful bleeding and uterine tenderness, BUT the stem describes a soft, nontender uterus and no vaginal bleeding or pain, arguing against abruption.

A. Granulosa cell tumor

This option implies an estrogen-secreting sex cord–stromal tumor causing endometrial hyperplasia, precocious puberty, or abnormal uterine bleeding, BUT this patient has clear androgenic virilization and elevated testosterone, not estrogenic manifestations.

B. Ovarian thecoma

This option implies a benign sex cord–stromal tumor that usually secretes estrogen and presents with postmenopausal bleeding or endometrial hyperplasia, BUT this patient has testosterone-mediated virilization and laboratory-confirmed androgen excess.

C. Dermoid cyst

This option implies a mature cystic teratoma, which is typically hormonally inactive and presents as an incidental adnexal mass, BUT it does not cause androgen excess, virilization, or isolated testosterone elevation.

D. Ovarian dysgerminoma

This option implies a malignant germ cell tumor that may elevate LDH or hCG, presenting with pelvic mass and pain, BUT it is not an androgen-secreting tumor and does not explain the marked virilization with elevated testosterone.

E. Serous cystadenoma

This option implies a benign epithelial ovarian tumor that is usually hormonally silent and presents with a simple cystic mass, BUT it does not cause virilization or elevated testosterone levels.

A. Measurement of mid-luteal progesterone concentration

This option implies suspected anovulation, which causes irregular or absent menses, BUT she has regular cycles, making ovulatory dysfunction less likely than uterine adhesions.

B. Measurement of antisperm antibody concentration

This option implies immunologic infertility, which is rare and not suggested here; BUT her history of postpartum D&C and scant menses directly points to intrauterine adhesions instead.

C. Estrogen/progestin withdrawal test

This option is used to assess amenorrhea or hypoestrogenism, BUT she is not amenorrheic—she has regular, though lighter, menses, so this test does not address the likely uterine cavity problem.

D. Measurement of serum FSH and LH concentrations

This option implies suspected ovarian failure or hypothalamic dysfunction, which would typically cause cycle irregularity or amenorrhea, BUT her cycles are regular, pointing away from a primary hormonal cause.

F. Dilation and curettage

This option implies treatment for retained products or diagnostic sampling, BUT additional D&C could worsen intrauterine adhesions, not diagnose/treat them safely like hysteroscopic adhesiolysis.