NCLEX Review Guide: Maternal Newborn Health - Reproductive System, Pelvis and Measurements

External Structures (Vulva)

• Mons pubis: Fatty tissue over symphysis pubis that provides protection during intercourse
• Labia majora: Larger outer folds that protect internal structures and contain sebaceous glands
• Labia minora: Smaller inner folds that are highly vascular and sensitive to hormonal changes
• Clitoris: Erectile tissue with extensive nerve supply, homologous to male penis
• Vestibule: Contains urethral and vaginal openings, Bartholin's and Skene's glands

Internal Structures

• Vagina: Muscular tube 8-10cm long with rugae that allow expansion during childbirth
• Cervix: Lower portion of uterus with internal and external os that dilates during labor
• Uterus: Pear-shaped organ with fundus, body, and cervix; weighs 60g non-pregnant, 1000g at term
• Fallopian tubes: 10cm tubes with fimbriae that capture ovum and provide fertilization site
• Ovaries: Almond-shaped organs that produce ova and hormones (estrogen, progesterone)

Pelvic Types

Critical Pelvic Measurements

• Pelvic inlet (superior strait): Diagonal conjugate ≥11.5cm indicates adequate space for fetal head engagement
• Midpelvis (cavity): Narrowest part where arrest commonly occurs during labor
• Pelvic outlet (inferior strait): Intertuberous diameter ≥8cm allows fetal head to pass through
• True conjugate: Shortest AP diameter (10.5-11cm) from sacral promontory to symphysis pubis

Pelvic Examination Procedure

1. Position client in lithotomy position with proper draping for privacy
2. Inspect external genitalia for lesions, discharge, or anatomical variations
3. Insert speculum to visualize cervix and obtain specimens if needed
4. Perform bimanual examination to assess uterine size, position, and adnexal masses
5. Measure pelvic dimensions using pelvimeter or clinical estimation

Common Abnormalities

• Contracted pelvis: Any diameter 1-2cm smaller than normal, may prevent vaginal delivery
• Pelvic inflammatory disease (PID): Infection causing scarring and potential fertility issues
• Uterine prolapse: Descent of uterus into vaginal canal due to weakened pelvic floor
• Ovarian cysts: Fluid-filled sacs that may cause pelvic pain or rupture

• ☐ Can you identify the four pelvic types and their delivery implications?
• ☐ Do you know the minimum diagonal conjugate measurement for adequate pelvis?
• ☐ Can you explain the difference between true and false pelvis?
• ☐ Do you understand when CPD is suspected and nursing interventions?
• ☐ Can you describe proper positioning for pelvic examination?