Saudi Board OB/GYN Part 1 Complete Review Guide 2026–2027

4. Android pelvis: prominent spines, convergent walls and a narrow arch. It predisposes to deep transverse arrest.
5. Platypelloid pelvis: short AP and wide transverse inlet. The head engages transversely and may fail to enter the inlet.
6. Outlet contraction: intertuberous diameter of 8 cm or less. The head is pushed back onto the perineum and tears become more likely.
7. The uterine artery comes from the anterior division of the internal iliac artery. The ovarian artery arises from the aorta below the renal arteries.
8. Ovarian vessels run in the infundibulopelvic ligament. It is secured at oophorectomy after the ureter is identified.
9. The cardinal ligament is the main lateral support of the cervix and vaginal apex, and carries the uterine vessels.
10. The round ligament passes through the inguinal canal to the labium majus. Its stretch causes sharp groin pain in pregnancy.
11. Cervical lymph drains to parametrial, obturator and iliac nodes. Ovarian lymph follows the ovarian vessels to para-aortic nodes.
12. Fundal and cornual lymph can follow the round ligament to superficial inguinal nodes. Vulval lesions within 2 cm of the midline may drain to both groins.
13. The pudendal nerve (S2 to S4) curves around the ischial spine and sacrospinous ligament. Inject just medial and posterior to the spine, aspirating first.
14. Puborectalis slings around the anorectal junction and keeps the anorectal angle. It is maximally stretched at crowning.
15. POP-Q uses the hymen as zero. Point C at +3 means failure of apical (level I) support, the cardinal-uterosacral complex.
16. The right ovarian vein drains into the IVC, so postpartum right ovarian vein thrombosis can extend into it.
17. Near the cervix the ureter passes beneath the uterine artery, 1.5 to 2 cm lateral. Clamping the uterine pedicle here is the commonest cause of injury.
18. At the pelvic brim the ureter crosses the iliac bifurcation, medial to the ovarian vessels. See it before sealing them.
19. A low transverse uterine incision bleeds less and carries a lower later rupture risk than a classical incision.
20. In thin women the aortic bifurcation lies close below the umbilicus, so angle the Veress needle about 45° caudally. After midline laparotomies, use Palmer's point.
21. Pelvic splanchnic nerves (S2 to S4) are parasympathetic and contract the detrusor. Damage to the inferior hypogastric plexus at radical hysterectomy causes retention.
22. Below the arcuate line there is no posterior rectus sheath, only transversalis fascia and peritoneum. A rectus sheath haematoma can spread into the prevesical space.
23. Inferior epigastric vessels lie in the lateral umbilical fold; place lateral ports outside them under vision. Close fascia at ports of 10 mm or more.
24. About 75% of breast lymph drains to axillary nodes. The long thoracic nerve lies on the medial axillary wall; injury causes a winged scapula.

Common mistakes in this chapter

• ✕ The diagonal conjugate is confused with the obstetric conjugate. The diagonal is measured clinically; subtract 1.5 to 2 cm to estimate the obstetric conjugate.
• ✕ The ureter is often placed above the uterine artery. It passes beneath it (water under the bridge), about 1.5 to 2 cm lateral to the cervix.
• ✕ Both ovarian veins are assumed to drain into the IVC. The right drains into the IVC; the left drains into the left renal vein.
• ✕ The ureter is often named as the most injured urinary organ in gynaecological surgery. The bladder is injured more often.
• ✕ Methylene blue test: a wet but unstained tampon means a ureterovaginal fistula; a blue tampon means a vesicovaginal fistula.
• ✕ A T10 to L1 epidural block is assumed to cover the second stage. Perineal pain travels in the pudendal nerve and needs S2 to S4.
• ✕ Internal iliac ligation is thought to stop pelvic flow. It mainly lowers distal pulse pressure, and collateral flow is preserved.
• ✕ More than 50% of the external sphincter torn with an intact internal sphincter is 3b, not 3a; anorectal epithelium involvement is fourth degree.