Lange Q&A Obstetrics And Gynecology, 9th Edition.

Contents Student Reviewers Preface Abbreviations USMLE Step 2 CKLaboratory Values 1. Anatomy Questions Answers and Explanations 2. Histology andPathology Questions Answers and Explanations 3. Embryology Questions Answers and Explanations 4. Genetics andTeratology Questions Answers and Explanations 5. Physiology of Reproduction Questions Answers and Explanations 6. Maternal Physiology During Pregnancy Questions Answers and Explanations 7. Placental, Fetal, andNewbornPhysiology Questions Answers and Explanations 8. Prenatal Care Questions Answers and Explanations 9. Diseases Complicating Pregnancy Questions Answers and Explanations 10. Normal Labor and Delivery Questions Answers and Explanations 11. Abnormal Labor andDelivery Questions Answers and Explanations 12. Operative Obstetrics Questions Answers and Explanations 13. Puerperium Questions Answers and Explanations 14. NewbornAssessment and Care Questions Answers and Explanations 15. Infertility Questions Answers and Explanations 16. Clinical Endocrinology Questions Answers and Explanations 17. Contraception Questions Answers and Explanations 18. Gynecology: Common Lesions of the Vulva, Vagina, Cervix, and Uterus; Gynecologic Pain Syndromes; Imaging inObstetrics and Gynecology Questions Answers and Explanations 19. Pelvic Floor Dysfunction: Genital Prolapse and Urogynecology Questions Answers and Explanations 20. The Pelvic Mass Questions Answers and Explanations 21. Gynecologic Oncology: Premalignant and Malignant Diseases of the Lower Genital Tract— Vulva, Vagina, andCervix Questions Answers and Explanations. 22. Gynecologic Oncology: UpperGenital Tract Benign andMalignant Conditions Questions Answers and Explanations 23. Breast Cancer Questions Answers and Explanations 24. Infectious Diseases inObstetrics andGynecology Questions Answers and Explanations 25. Special Topics in Gynecology: Pediatric and Adolescent Gynecology, Sexual Abuse, Medical Ethics, andMedical–Legal Considerations Questions Answers and Explanations 26. Primary HealthCare forWomen Questions Answers and Explanations 27. Practice Test Questions Answers and Explanations References Index Student Reviewers AdamDarnobid, MD Resident Physician UMass Memorial Medical Center Worcester, Massachusetts Class of 2009 Barrett Little Temple University School of Medicine Philadelphia, Pennsylvania Class of 2010 Radhika Lu Sundararajan New York University School of Medicine New York, New York Class of 2010 Preface Education is the kindling of a flame, not the filling of a vessel. —Socrates The ninth edition of Lange Q&A: Obstetrics and Gynecology book has been written, as were the prior editions, to be a study aid for self-examination and review in the field of obstetrics and gynecology. Each chapter has been updated with new questions written to cover new information. These encompass new areas in the field, updates in other areas, and some of the new clinical guidelines from national organizations. The questions are designed to review many topics commonly covered in tests such as the clerkship examination and United States Medical Licensing Examination (USMLE) Step 2 CK. The style and presentation of the questions have been fully revised to conform with the USMLE. This will enable readers to familiarize themselves with the types of questions to be expected and practice answering questions in each board format used in the actual examination. The majority of questions are multiplechoice one best answer-single-item questions. For these questions, you will choose the one best response to the question. Some questions are matching sets consisting of a group of questions preceded by a list of lettered options. For these questions you will select one lettered option that is most closely associated with the question. In some cases, a group of two or three questions may be related to one patient situation. These questions—often called second- or third-order questions—will require you to think through the entire set of questions to reach the correct answers in the patient scenario. Since the USMLE seems to prefer questions requiring judgment and critical thinking, we have attempted to emphasize these questions. In addition, some questions have images that require understanding and interpretation to reach the correct answer. Each chapter of this book presents questions covering important topics in the obstetrics and gynecology specialty. The question sections are followed by a section containing the answers and explanations. These answer sections provide background information on the subject matter and discuss the various issues raised by the question and its answer. After answering a question, we encourage you to review the explanations further—even if you have answered the question correctly—to enhance your study and understanding. These explanations will often discuss not only why one answer is correct, but also why the other choices are incorrect. This reinforces your knowledge and provides feedback to guide further study. At the end of the book we have included a practice test that contains randomly ordered questions of all styles covering all the topics. This test is designed to more closely approximate the form of the USMLE Step 2 CK examination. An answer and comment section follows the practice test and relates to the questions contained in it. We hope that using this review will help you consolidate your knowledge, evaluate your capabilities, and motivate you to continually expand your horizons to levels far beyond this study aid. Abbreviations ABH: A and B are blood antigens; H is the substrate from which they are formed. ACTH: adrenocorticotropic hormone ADH: antidiuretic hormone AFP: alpha1 fetoprotein AP: anteroposterior ATN: acute tubular necrosis B: basophils BMR: basal metabolic rate BP: blood pressure BSO: bilateral salpingo-oophorectomy BSU: Bartholin, Skene& and urethral glands CAH: congenital adrenal hyperplasia CHD: congenital heart disease CHF: congestive heart failure CIN: cervical intraepithelial neoplasia CNS: central nervous system CP: cerebral palsy CPD: cephalic disproportion CSF: cerebrospinal fluid CST: contraction stress test D&C: dilation and curettage DES: diethylstilbestrol DHEA: dehydroepiandrosterone DHEAS: dehydroepiandrosterone sulfate DIC: disseminated intravascular coagulation E: eosinophils E3: estriol EDC: estimated date of confinement ESR: erythrocyte sedimentation rate EUA: examination under anesthesia 5-FU: 5-fluorouracil FHTs: fetal heart tones FIGLU: formiminoglutamic acid FIGO: International Federation of Gynecology and Obstetrics FSH: follicle-stimulating hormone FTA: fluorescent treponemal antibody (test) G6 PD: glucose-6-dehydrogenase deficiency GH: growth hormone GI: gastrointestinal GU: genitourinary HbA: adult hemoglobin HbF: fetal hemoglobin HCG: human chorionic gonadotropin HCS: human chorionic somatomammotropin Hct: hematocrit H&E: hematoxylin and eosin (stain) HLA: histocompatibility locus antigen HPF: hepatic plasma flow HPV: human papilloma virus ICSH: interstitial-cell stimulating hormone INH: isonicotinoylhydrazine IRDS: infant respiratory distress syndrome IVP: intravenous pyelogram KUB: kidneys, ureters, & bladder L: lymphocytes LE: lupus erythematosus LH: luteinizing hormone LHRH: luteinizing hormone-releasing hormone LMP: last menstrual period LMT: left mentotransverse LOA: left occipito-anterior LOP: left occiput posterior LOT: left occiput transverse L/S: lecithin/sphingomyelin LSB: left sternal border LST: left sacrotransverse M: monocytes MCH: mean corpuscular hemoglobin MCHC: mean corpuscular hemoglobin concentration MCV: mean corpuscular volume MeV: mega electron volt MF: menstrual formula MI: maturation index müuuml;llerian-inhibiting factor MmmIF: : muscles MMK: Marshall-Marchetti-Krantz procedure NST: nonstress test OA: occipito-anterior OCT: oxytocin challenge test OD: optical density OP: occiput posterior OR: operating room P: plasma cells PAS: para-aminosalicylic acid PBI: protein-bound iodine PG: prostaglandin PID: pelvic inflammatory disease PIF: prolactin-inhibiting factor PKU: phenylketonuria ROP: right occipitoposterior SGOT: serum glutamic-oxaloacetic transaminase SLE: systemic lupus erythematosus SRT: sacrum right transverse SS: sickle cell anemia TAH: total abdominal hysterectomy TB: tuberculosis TNM: tumor, node, metastasis TRH: thyrotropin-releasing hormone TSH: thyroid-stimulating hormone UA: urinalysis UPD: urinary production (rate) UTI: urinary tract infection WBC: white blood cell count USMLE Step 2 CK Laboratory Values "° Hemogrobln A,. tla1noglobh1, blood lobln,plasma LeUIDC'JIB oount and doifar ntia! llllo:,um Segmented . 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Ii 26-711 i'l10/24 h 2:l s.!µmOl/2,II h 0.a ll Po ssium - 1 S,Qclium Uric t ll'IN S--4011 Vativswid!Olel 150 '2 i'I VaAa· .-nlll I Varies , de'! 9G--4JSµm VilfNIS wdl di91 .15 1, Vaooi I ailll Varifr.;.wlllldi&i CHAPTER 1 Anatomy Questions DIRECTIONS (Questions 1 through 35): For each of the multiple choice questions in this section, select the lettered answer that is the one best response in each case. 1. A healthy 5 ft 6 in. tall, adult female is most likely to have a pelvic inlet that would be classified as which of the following Caldwell-Moloy types? (A) android (B) platypelloid (C) anthropoid (D) gynecoid (E) triangular 2. Hernias occur more commonly in men than in women beneath the thickened lower margin of a fascial aponeurosis extending from the pubic tubercle to the anterior superior iliac spine. This thickened fascia is called which of the following? (A) inguinal ligament (B) Cooper’s ligament (C) linea alba (D) posterior rectus sheath (E) round ligament 3. The inguinal canal in an adult female was opened surgically. Which of the following structures would normally be found? (A) a cyst of the canal of Nuck (B) Gartner’s duct cyst (C) Cooper’s ligament (D) the round ligament and the ilioinguinal nerve (E) the pyramidalis muscle 4. The human pelvis is a complex structure that permits upright posture and being capable with childbirth despite the relatively large fetal head. Which option includes all of the bones that make up the pelivs? (A) trochanter, hip socket, ischium, sacrum, and pubis (B) ilium, ischium, pubis, sacrum, and coccyx (C) ilium, ischium, and pubis (D) sacrum, ischium, ilium, and pubis (E) trochanter, sacrum, coccyx, ilium, and pubis 5. During normal delivery, an infant must pass through the maternal true pelvis. Which of the following most accurately describes the characteristics of the true pelvis? (A) It has an oval outlet. (B) It has three defining planes: an inlet, a midplane, and an outlet. (C) It has an inlet made up of a double triangle. (D) It is completely formed by two fused bones. (E) It lies between the wings of the paired ileum. 6. The part of the pelvis lying above the linea ter-minalis has little effect on a woman’s ability to deliver a baby vaginally. What is the name of this portion of the pelvis? (A) true pelvis (B) midplane (C) outlet (D) false pelvis (E) sacrum 7. The plane from the sacral promontory to the inner posterior surface of the pubic symphysis is an important dimension of the pelvis for normal delivery. What is the name of this plane? (A) true conjugate (B) obstetric conjugate (C) diagonal conjugate (D) bi-ischial diameter (E) oblique diameter 8. During an operation, a midline incision was made at an anatomic location 2 cm below the umbilicus. Which of the following lists (in order) the layers of the anterior abdominal wall as they would be incised or separated? (A) skin, subcutaneous fat, superficial fascia (Camper’s), deep fascia (Scarpa’s), fascial muscle cover (anterior rectus sheath), rectus muscle, a deep fascial muscle cover (posterior rectus sheath), preperitoneal fat, and peritoneum (B) skin, subcutaneous fat, superficial fascia (Scarpa’s), deep fascia (Camper’s), fascial muscle covering (anterior abdominal sheath), transverse abdominal muscle, a deep fascial muscle cover (posterior rectus sheath), preperitoneal fat, and peritoneum (C) skin, subcutaneous fat, superficial fascia (Camper’s), deep fascia (Scarpa’s), fascial muscle cover (anterior rectus sheath), rectus muscle, a deep fascial muscle cover (posterior rectus sheath), peritoneum, and preperitoneal fat (D) skin, subcutaneous fat, superficial fascia (Scarpa’s), deep fascia (Camper’s), fascial muscle cover (anterior rectus sheath), rectus muscle, a deep fascial muscle cover (posterior rectus sheath), preperitoneal fat, and peritoneum (E) skin, subcutaneous fat, superficial fascia (Camper’s), deep fascia (Scarpa’s), fascial muscle cover (anterior rectus sheath), transverse abdominal muscle, a deep fascial muscle covering (posterior rectus sheath), preperitoneal fat, and peritoneum 9. Under the influence of relaxin and the pressure of pregnancy the junction between the two pubic bones may become unstable near the time of delivery. This will result in a waddling gait in the woman to minimize discomfort. What is this junction called? (A) sacroiliac joint (B) symphysis (C) sacrococcygeal joint (D) piriformis (E) intervertebral joint 10. The shape of the escutcheon may change with masculinization. The presence of a male escutcheon in a female is one of the clinical signs of hirsutism or increased testosterone. What is the usual shape of the escutcheon in the normal female? (A) diamond shaped (B) triangular (C) oval (D) circular (E) heart shaped 11. During the performance of a pelvic examination, the area of the Bartholin’s ducts should be inspected. Where do the Bartholin’s glands’ ducts open? (A) into the midline of the posterior fourchette (B) bilaterally, beneath the urethra (C) bilaterally, on the inner surface of the labia majora (D) bilaterally, into the posterior vaginal vestibule (E) bilaterally, approximately 1 cm lateral to the clitoris 12. During a physical examination myrtiform caruncles may be noted. What are they? (A) circumferential nodules in the areola of the breast (B) healing Bartholin’s cysts (C) remnants of the Wolffian duct (D) remnants of the hymen (E) remnants of the Müllerian duct 13. The clitoris is a major sensory sexual organ. Where does it get its major nerve supply from? (A) lumbar spinal nerve (B) pudendal nerve (C) femoral nerve (D) ilioinguinal nerve (E) anterior gluteal nerve 14. In the uterus of a normal female infant, what is the size relationship of the cervix, isthmus, and fundus? (A) The cervix is larger than the fundus. (B) The isthmus is longer than either the cervix or the fundus. (C) They are of equal size. (D) The fundus is the largest portion. (E) The cervix is smaller than either the isthmus or the fundus. 15. How do nabothian cysts occur? (A) Wolffian duct remnants (B) blockage of crypts in the uterine cervix (C) squamous cell debris that causes cervical irritation (D) carcinoma (E) paramesonephric remnants 16. What is the uterine corpus mainly composed of? (A) fibrous tissue (B) estrogen receptors (C) smooth muscle (D) elastic tissue (E) endometrium 17. The uterus and adnexa have some relatively fixed anatomic characteristics that can be noted on pelvic examination or laparoscopic observation. Which of the following characteristics would you most likely find in a normal patient? (A) retroflexion of the uterus (B) ovaries caudad to the cervix (C) round ligaments attached to the uterus posterior to the insertion of the fallopian tubes (D) immobility of the uterus (E) cervix not palpable on rectal examination 18. A patient presents approximately 10 years post-menopausal with complaints of pressure vaginally and the sensation that something is falling out. When told she has a fallen uterus, she wonders if it is due to the damage from her round ligaments since she had a great deal of round ligament pain during her pregnancies. Which of the following ligaments provide the most support to the uterus in terms of preventing prolapse? (A) broad ligaments (B) round ligaments (C) utero-ovarian ligaments (D) cardinal ligaments (E) arcuate ligament 19. Pelvic inflammatory disease (PID) occurs in women because of which of the following characteristics of the fallopian tube? (A) It is a conduit from the peritoneal space to the uterine cavity. (B) It is found in the utero-ovarian ligament. (C) It has five separate parts. (D) It is attached to the ipsilateral ovary by the mesosalpinx. (E) It is entirely extraperitoneal. 20. In a female, which of the following best describes the urogenital diaphragm? (A) includes the fascial covering of the deep transverse perineal muscle (B) encloses the ischiorectal fossa (C) is synonymous with the pelvic diaphragm (D) is located in the anal triangle (E) envelops the Bartholin’s gland 21. The levator ani is the major component of the pelvic diaphragm, which is commonly compromised during pregnancy and delivery with resulting prolapse of uterus, bladder/urethra, and /or rectum. This is especially true if obstetric lacerations are not repaired keeping the normal anatomical relationships in mind. Which of the following is the best description of the levator ani? (A) a superficial muscular sling of the pelvis (B) a tripartite muscle of the pelvic floor penetrated by the urethra, vagina, and rectum (C) is made up of the bulbocavernosus, the ischiocavernosus, and the superficial transverse perineal muscle (D) a muscle that abducts the thighs (E) is part of the deep transverse perineal muscle 22. Which of the following is the best description of the pelvic diaphragm? (A) made up mainly by the coccygeus (B) covered on one side by fascia and on the other by peritoneum (C) a muscle innervated by L2, L3, and L4 (D) an extension of the sacrococcygeal ligament (E) synonymous with the pelvic floor 23. When performing a hysterectomy, the surgeon should be aware that at its closest position to the cervix, the ureter is normally separated from the cervix by which of the following distances? (A) 0.5 mm (B) 1.2 mm (C) 12 mm (D) 3 cm (E) 5 cm 24. When performing surgery, the position of important structures should be well known to avoid injury. What is the ureter’s relationship to the arteries in its course through the pelvis? (A) anterior to the internal iliac and uterine arteries (B) posterior to the iliac artery and anterior to the uterine artery (C) anterior to the uterine artery and posterior to the iliac artery (D) posterior to the uterine artery and medial to the iliac artery (E) posterior to the uterine artery and posterior to the hypogastric artery 25. Urinary incontinence is a major problem for some women. Which of the following characteristics of the female urethra helps prevent incontinence? (A) its 15- to 20-cm length (B) its junction with the bladder at the level of the midtrigone (C) its true anatomic sphincter (D) its upper two-thirds integration with the anterior vaginal wall (E) its intrinsic resting tone 26. The anatomy of the spinal cord and dural space is important when giving regional spinal anesthesia. At what approximate spinal level do the dural space and the spinal cord, respectively, end? (A) T10, T8 (B) L2, T10 (C) L5, T12 (D) S2, L2 (E) S5, S2 27. During a hysterectomy, vaginal bleeding may be a significant complication even after removal of the uterus. Such bleeding would most likely originate from which of the following arteries? (A) internal pudendal (B) superior hemorrhoidal (C) inferior mesenteric (D) superior vesical (E) ovarian 28. Anterior vulvar cancer is most likely to spread primarily to which of the following lymph nodes? (A) inguinal (B) para-aortic (C) obturator (D) femoral (E) ovarian 29. Which artery provides the main blood supply to the vulva? (A) pudendal (B) inferior hemorrhoidal (C) ilioinguinal (D) femoral (E) inferior hypogastric 30. During delivery, which of the following muscles is most likely to be obviously torn? (A) ischiocavernosus muscle (B) bulbocavernosus muscle (C) superficial transverse perineal muscle (D) levator ani muscle (E) coccygeus 31. A patient develops a neurologic disease that destroys components of S2, S3, S4 bilaterally. What clinical manifestation would you expect the patient to have as a result? (A) inability to abduct her thigh (B) rectal incontinence (C) painless menses (D) labor without pain (E) inability to extend her knees 32. A 56-year-old woman comes to your office for a yearly examination. During physical examination, you notice that her left breast has a 2-cm area of retraction in the upper-outer quadrant that can be seen by simple inspection. What is the most likely diagnosis? (A) Mondor’s disease (B) benign fibroadenoma (C) fibrocystic change (D) breast cancer (E) intraductal polyp 33. A woman who is 32 weeks pregnant comes in complaining of lumps in her breasts. These lumps are multiple in number and on inspection are within the areola. By palpation they seem to be small, superficial, uniform in size, nontender, and soft. What is the most likely diagnosis? (A) Mondor’s disease (B) Montgomery’s follicles (C) inflammatory breast carcinoma (D) fibrocystic breast changes (E) lactiferous ducts 34. A woman has a radical hysterectomy and pelvic lymphadenectomy for Stage I carcinoma of the cervix. After surgery she complains that she cannot adduct her left leg and there is an absence of sensation on the medial aspect of her left thigh. What is the most likely explanation? (A) injury to the obturator nerve (B) femoral nerve injury (C) hematoma in the pouch of Douglas (D) injury to the uterosacral nerve (E) injury to the pudendal nerve 35. During delivery of a first twin, a very tight nuchal cord is reduced from the baby’s neck by clamping and dividing it. After this, the second twin (as yet unborn) develops severe fetal distress. Of the following, what is the most likely mechanism for the distress in the second twin? (A) a twin-to-twin transfusion before birth (B) the second twin may no longer be connected to its placenta (C) placenta previa in the second twin (D) amniotic fluid embolism (E) uterine rupture DIRECTIONS (Questions 36 through 59): The following groups of questions are preceded by a list of lettered options. For each question, select the one lettered option that is most closely associated with it. Each lettered option may be used once, multiple times, or not at all. Questions 36 through 39 (A) a thick band of fibers filling the angle created by the pubic rami (B) passes from the anterior superior iliac spine to the pubic tubercle (C) triangular and extends from the lateral border of the sacrum to the ischial spine (D) attaches to the crest of the ilium and the posterior iliac spines superiorly with an inferior attachment to the ischial tuberosity (E) passes over the anterior surface of the sacrum 36. Sacrospinous ligament 37. Sacrotuberous ligament 38. Ilioinguinal ligament 39. Arcuate ligament Questions 40 through 43 (A) obturator foramen (B) greater sciatic foramen (C) lesser sciatic foramen (D) sacrospinous ligament (E) pudendal (Alcock’s) canal (F) sacral foramina 40. Formed by the superior and inferior pubic rami and covered by a central membrane through which a nerve, artery, and vein pass 41. The internal pudendal vessels and pudendal nerve exit the pelvis but then reenter through this structure 42. Divides and demarcates the greater and lesser sciatic foramen 43. A sheath of fascia on the lateral wall of the ischiorectal fossa containing vessels and nerve Questions 44 through 49 (A) anterior hypogastric nerve (T12) (B) posterior iliac nerve (T12–L1) (C) ilioinguinal nerve (L1) (D) genitofemoral nerve (L1–L2) (E) the pudendal nerve (S2, S3, S4) (F) terminal branch of the pudendal nerve 44. Mons veneris and anterior labia majora 45. Gluteal area 46. Anterior and medial labia majora 47. Deep labial structures 48. Main innervation of the labia 49. Clitoris Questions 50 through 56 (A) Battledore placenta (B) bipartite placenta (C) circumvallate placenta (D) multiple-pregnancy placenta (E) placenta accreta (F) placenta previa (G) succenturiate lobe 50. A small central chorionic plate surrounded by a thick whitish ring, associated with increased rates of perinatal bleeding and fetal death 51. An accessory cotyledon that is possible not to remove with the placenta at birth and cause post-partum atony and hemorrhage 52. Divided into two lobes 53. Umbilical cord inserted at the placental margin 54. Placenta abnormally adherent to the myometrium 55. Placenta covers the cervical os 56. May be distinct entities or fused Questions 57 through 59: For each of the following postoperative patients with areas of skin anesthesia, pain, and/or muscle weakness, select the most likely cause. (A) electrolyte imbalance (B) obturator nerve injury (C) pudendal nerve injury (D) femoral nerve injury (E) disruption of peripheral (skin) nerves (F) ilioinguinal nerve injury (G) spinal cord injury (H) sciatic nerve injury (I) diabetes 57. A 56-year-old white woman who had paravaginal suspension and Burch procedure 2 days ago complains of pain over the right mons pubis, right labia, and right medial thigh. 58. A 36-year-old patient who underwent a total abdominal hysterectomy for uterine fibroids complains of weakness of her left leg and numbness of her left anterior medial thigh. 59. A patient, following a pelvic lymphadenectomy for cervical cancer, complains of some numbness in the medial thigh. On examination, she is found to have full range of motion of her leg, but weakness to adduction. Answers and Explanations 1. (D) Pelvises in most U.S. women are gynecoid, but they may be of a mixed type (for instance, having a gynecoid forepelvis and an anthropoid posterior pelvis). The obstetrician has to judge the capacity of the pelvis on the basis of its total configuration, including midplane and outlet capacities, and always in relation to the size and position of the fetus. 2. (A) From the pubic tubercle to the anterior superior iliac spine, the thickened lower margin of the fascial aponeurosis forms the inguinal ligament. This aponeurosis of the external oblique muscle fuses with its counterpart from the opposite side and with the underlying internal oblique fascia. Cooper’s ligament is a thickening of fascia along the pubic bone. The linea alba is in the midline and the round ligament attaches to the uterus. 3. (D) The superficial inguinal ring is just cepha-lad to the pubic tubercle and just lateral to it, the deep inguinal ring passes through the transver-salis fascia. The connection of these rings forms the inguinal canal. The round ligament, the ilioinguinal nerve, and the processus vaginalis pass out of the abdomen through this canal (as does the spermatic cord in the male). Gartner’s ducts are found in the lateral walls of the vagina. One would not normally find a cyst of the processus vaginalis (cyst of the canal of Nuck). 4. (B) The pelvis surrounds the birth passage, provides attachment for muscles and fascia, and includes the ilium, ischium, pubis, sacrum, and coccyx. The ilium, ischium, and pubic bone compose the innominate bone. 5. (B) The true pelvis has three planes: inlet, mid-plane, and outlet. It is made up of the paired ileum, ischium, and pubic bones, and the single sacrum and coccyx. The true pelvis is cau-dad to the false pelvis, which lies between the paired ileum wings. Its inlet is usually gynecoid. 6. (D) The false pelvis or pelvis major lies above the linea terminalis. It seldom affects obstetric management, and measurements of the iliac crest flare do not usually aid in determining the size of the true pelvis. An important measurable indicator of the size of the true pelvis is the inter-spinous diameter. 7. (B) The obstetric conjugate is the shortest line from the inside of the symphysis to the most prominent point on the front two segments of the sacrum. It defines what is often the smallest diameter of the pelvic inlet. It should be estimated during clinical examination (pelvimetry) and considered whenever evaluating a pelvis for possible cephalopelvic disproportion, especially during abnormalities of labor. It differs from the true conjugate, which is measured from the top of the symphysis, and also from the diagonal conjugate, which is measured clinically from the bottom of the symphysis to the sacral promontory. The biischial diameter is on the pelvic outlet. 8. (A) Layers at the midline of the abdominal wall, 2 cm below the umbilicus that would be incised or separated are skin, subcutaneous fat, superficial fascia (Camper’s), deep fascia (Scarpa’s), and the fascial muscle coverings (anterior rectus sheath). The rectus muscles would be separated and the deep fascial layer (posterior rectus sheath), preperitoneal fat, and peritoneum would be incised. The