Reproductive Health & the Family

Overview of Maternity Nursing

• Maternity Nursing Definition: Focuses primarily on the well-being of the mother and the fetus/infant.

• Support Philosophy: Supports the emotional, physical, and spiritual well-being of both clients (mother and infant).

• Care Provision: Provides personalized healthcare and professional advice.

• Family Dynamics: Extends support systems to the entire family unit.

Female Reproductive System: External Genitalia (Vulva)

The external structures of the female reproductive system consist of the following components:

• Mons Pubis: The fatty tissue layer covering the pubic symphysis.

• Labia Majora: The outer, larger folds of skin protecting the vaginal opening.

• Labia Minora: The inner, thinner folds located inside the labia majora.

• Clitoris: Includes the prepuce (hood), the head (glans), and the body; the primary organ of sexual sensation.

• Vestibule: The area enclosed by the labia minora containing several openings.

• Urethral Meatus: The external opening of the urethra where urine is discharged.

• Skene’s Glands: Also known as paraurethral glands; located near the urethral meatus.

• Hymen: A thin membrane that partially covers the vaginal orifice (introitus).

• Bartholin’s Glands: Glands that open into the vestibule to provide lubrication.

• Fourchette: The fold of skin forming the posterior margin of the vulva.

• Perineal Body: The fibromuscular structure between the vaginal opening and the anus.

Female Reproductive Organs: Internal Genitalia

The internal reproductive system is comprised of structures located within the pelvic cavity:

• Vagina: The muscular canal extending from the vulva to the cervix.

• Fornices: Recesses around the cervix within the vagina, divided into the Anterior Fornix and the Posterior Fornix.

• Uterus: The hollow, muscular organ where fetal development occurs.

  • Fundus: The upper, rounded portion of the uterus above the fallopian tube insertions.

  • Corpus: The main body of the uterus.

  • Cornua: The areas where the fallopian tubes enter the uterus.

  • Isthmus: The narrowed lower region of the uterus just above the cervix.

  • Cervix: The lower neck of the uterus, featuring an Internal Os (opening to the uterine cavity) and an External Os (opening to the vagina).

• Uterine Tissue Layers:

  • Endometrium: The inner mucosal lining; sheds during menstruation.

  • Myometrium: The thick, muscular middle layer responsible for contractions.

  • Perimetrium: The outer serous layer covering the uterus.

• Fallopian Tubes: Tubes which transport the ovum from the ovary to the uterus.

  • Interstitial (Intrauterine) Part: The segment within the uterine wall.

  • Isthmus: The narrow portion near the uterus.

  • Ampulla: The wider, middle portion where fertilization typically occurs.

  • Infundibulum: The distal, funnel-shaped end.

  • Fimbriae: Finger-like projections that "sweep" the ovum into the tube.

• Ovaries: Female gonads responsible for producing ova and hormones (Estrogens and Progesterones).

  • Cortex: Contains the ovarian follicles.

  • Tunica Albuginea: The protective fibrous covering.

  • Germinal Epithelium: The outermost layer of the ovary.

Uterine Ligaments and Pelvic Support

Several ligaments maintain the position of the internal reproductive organs:

• Broad Ligament: A wide fold of peritoneum that supports the uterus, ovaries, and fallopian tubes.

• Round Ligament: Extends from the uterine horns to the labia majora; helps keep the uterus in an anteverted position.

• Uterosacral Ligament: Connects the uterus to the sacrum.

• Cardinal Ligament: Provides primary support for the cervix and uterus.

• Ovarian Ligament: Connective tissue connecting the ovary to the uterus.

• Infundibulopelvic (Suspensory) Ligament: Houses the ovarian vessels and attaches the ovary to the pelvic wall.

• Supporting Cavities: Includes the Pouch of Douglas (rectouterine pouch) located between the uterus and the rectum.

The Bony Pelvis

The pelvis is divided into regions based on the Linea Terminalis (pelvic brim):

• False Pelvis: The portion above the pelvic brim; supports the weight of the pregnant uterus.

• True Pelvis: The bony canal through which the fetus must pass.

  • Pelvic Inlet: The upper entry to the true pelvis.

  • Pelvic Cavity: The mid-portion of the true pelvis.

  • Pelvic Outlet: The lower exit of the true pelvis.

• Vital Measurements:

  • Transverse Diameter: Approximately $13.5\,cm$.

  • Interspinous Diameter: Distance between ischial spines, approximately $10.5\,cm$.

  • Obstetric Conjugate: The shortest anteroposterior diameter through which the fetal head must pass, approximately $10\,cm$.

External Structures: The Breasts

Primary structures involved in lactation include:

• Nipple and Areola: The external projections and pigmented area.

• Alveoli: Glandular tissue responsible for milk production.

• Lactiferous Ducts: Tubes that carry milk to the nipple.

• Ampulla: Dilated portions of the ducts that serve as reservoirs.

• Cooper’s Ligaments (Suspensory Ligaments): Connective tissue that provides support and shape to the breast.

• Adipose Tissue: Fatty tissue comprising the bulk of the non-lactating breast.

Female Hormones and Reproductive Cycles

• Key Hormones:

  • Estrogens: Regulate the development of female secondary sex characteristics.

  • Progesterones: Maintain the pregnancy and uterine lining.

  • Prostaglandins: Inflammatory mediators that affect uterine smooth muscle.

  • Follicle-Stimulating Hormone (FSH): Triggers follicle maturation.

  • Luteinizing Hormone (LH): Triggers ovulation.

• Ovarian Cycle (Ideal 28-day cycle):

  1. Follicular Phase (Days 1–14): An immature follicle matures due to FSH; the oocyte grows, and the mature ovum is discharged into the fallopian tube fimbria.

  2. Luteal Phase (Days 15–28): The ovum leaves the follicle. If fertilized, it remains in the ampulla for $12\text{ to }24\,hours$. It reaches the uterus in $72\text{ to }96\,hours$ and secretes Human Chorionic Gonadotropin (hCG). If no fertilization occurs, the corpus luteum degenerates.

• Menstrual (Uterine) Cycle Phases:

  1. Menstrual Phase: Shedding of the functional layer of the endometrial cells.

  2. Proliferative Phase: Endometrial cells enlarge and thicken due to rising estrogen levels; cervical mucus becomes thin, clear, and elastic to facilitate sperm transport.

  3. Secretory Phase: Driven by progesterone; uterine vascularity increases to create a nourishing bed for implantation.

  4. Ischemic Phase: Occurs if implantation fails; hormone levels drop, the corpus luteum degenerates, and bleeding begins (the return to the menstrual phase).

Male Reproductive System

• External Genitalia:

  • Penis: Contains the urethra, corpus cavernosum, and corpus spongiosum.

  • Scrotum: The sac containing the testes.

• Internal Organs:

  • Testes: Site of sperm production.

  • Epididymis: Site of sperm maturation and storage.

  • Vas Deferens: Duct that transports sperm to the ejaculatory ducts.

  • Ejaculatory Ducts: Transfer sperm into the urethra.

  • Accessory Glands: Include the Seminal Vesicles, Prostate Gland, and Bulbourethral (Cowper's) Gland, which contribute to semen volume and alkalinity.

• Spermatozoon Structure:

  • Head: Contains the nucleus and Acrosome (enzymes for penetration).

  • Middle Piece: Packed with mitochondria for energy.

  • Tail (Flagellum): Provides motility.

Cellular Division and Gametogenesis

• Mitosis: Used for somatic growth and tissue repair; creates exact genetic copies of the original cell.

• Meiosis: The specialized division for gamete production; reduces chromosomes by half to ensure a normal number is restored at fertilization.

• Gametogenesis:

  • Oogenesis: Production of the ovum; all ova are present at birth in females.

  • Spermatogenesis: Production of sperm; begins at puberty in males.

Fertilization and Embryonic Development

• Fertilization Logistics:

  • Ova remain fertile for $12\text{ to }24\,hours$ post-ovulation.

  • Sperm can live $48\text{ to }72\,hours$ but are generally only fertile for the first $24\,hours$.

  • Fertilization occurs in the Ampulla of the fallopian tube.

  • A single sperm enters the ovum to form a Diploid Zygote ($XX$ for female, $XY$ for male).

• Embryonic Membranes:

  • Amnion: The inner membrane forming the amniotic cavity.

  • Chorion: The outer membrane with chorionic villi that becomes part of the placenta.

• Twinning:

  • Fraternal (Dizygotic): Developed from two separate ova and two sperm; results in two amnions and two chorions.

  • Identical (Monozygotic): Developed from one ovum and one sperm that splits; typically results in two amnions and one chorion.

Support Structures for the Fetus

• Amniotic Fluid:

  • Functions: Cushions the fetus, controls temperature, allows position changes, and promotes lung and musculoskeletal growth.

  • Composition: Formed from albumin, vernix, fetal urine, uric acid, lecithin, and sphingomyelin.

  • Pathologies: Mention of Polyhydramnios and Oligohydramnios (abnormal fluid levels).

• Umbilical Cord:

  • Contents: 1 vein (carries oxygenated blood to fetus) and 2 arteries (carry deoxygenated blood to placenta).

  • Wharton’s Jelly: Specialist connective tissue protecting the vessels from compression.

  • Innervation: No sensory or motor innervation.

• Placenta:

  • Functions: Respiration, excretion, nutrition, hormone production, and immunologic protection (prevents rejection of the fetal homograft).

  • Two Sides: Fetal side (shiny, umbilical cord attachment) and Maternal side.

Fetal Circulation Bypasses

Fetal circulation uses three specialized shunts to bypass the liver and lungs, which are not fully functional in utero:

• Ductus Venosus: Directs blood from the umbilical vein to the inferior vena cava, bypassing the liver.

• Foramen Ovale: An opening between the right and left atria, bypassing the lungs.

• Ductus Arteriosus: Connects the pulmonary artery to the descending aorta, further bypassing the lungs.

Fetal Development Milestones

• Week 4:

  • Heart begins to beat.

  • Arm and leg buds are visible.

  • Somites develop (beginning of vertebrae).

  • Primary lung buds and eyes/ears begin to form.

• Week 6:

  • Trachea is developed; nares are present.

  • Liver begins producing blood cells.

  • Heart begins circulating blood.

  • Digits develop; the tail begins to recede.

• Week 12:

  • Eyelids are closed; face is well-developed.

  • Tooth buds appear.

  • Genitals are differentiated.

  • Urine production and spontaneous movement begin.

  • Fetal heart tones can be heard (Dop-tone).

• Week 20:

  • Subcutaneous brown fat and vernix form.

  • Lanugo covers the body.

  • Mother feels movement (quickening).

  • Fetal heartbeat can be heard with a fetoscope.

• Week 24:

  • Eyes are structurally complete.

  • Alveoli begin to form; grasping and startle reflexes present.

  • Fingerprints/footprints present.

  • Viability: The fetus is considered viable at this stage.

• Week 28:

  • Rapid brain development; nervous system regulates body functions.

  • Eyelids open.

  • Testes begin to descend.

• Week 36:

  • Increase in subcutaneous fat.

  • Lanugo begins to disappear.

• Week 38:

  • Full Term: Reached at $37\text{ }0/7\text{ weeks}$.

  • Skin is smooth; vernix remains in folds.

  • Head is larger than the chest.