Reproductive Health and the Family

Female and Male Reproductive Systems

• Internal Female Genitalia: Consists of the vagina, uterus (corpus, fundus, cervix), fallopian tubes, and ovaries.

• Uterine Wall Layers:

  • Endometrium: Inner mucosal layer.

  • Myometrium: Muscular middle layer.

  • Perimetrium: Outer serosal layer.

• Uterine Support: Suspended in the pelvis by broad, round, uterosacral, cardinal, infundibulopelvic, and ovarian ligaments; attached only at the cervix.

• Fallopian Tube Sections: Divided into the isthmus, ampulla, infundibulum, and fimbriae.

• Bony Pelvis: Divided by the linea terminalis into the "false" pelvis and "true" pelvis (comprising the pelvic inlet, cavity, and outlet).

• Male Reproductive Organs:

  • External: Penis and scrotum.

  • Internal: Testes, epididymis, vas deferens, ejaculatory ducts, urethra, and accessory glands (seminal vesicles, prostate, bulbourethral/Cowper's glands).

Female Reproductive Cycle

• Hormonal Functions:

  • Estrogen: Stimulates maturation of ovarian follicles and proliferation of the endometrial mucosa.

  • Progesterone: Prepares the uterus for implantation, reduces uterine contractility, and prepares breasts for lactation.

  • Pituitary Hormones: Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH).

  • Prostaglandins: Essential for follicular rupture.

  • Corpus Luteum: Secretes progesterone until placental takeover.

• Ovarian Cycle Phases:

  • Follicular Phase (Days 1–14): Follicle matures under FSH/LH influence; oocyte grows and is discharged into the fallopian tube.

  • Luteal Phase (Days 15–28): Ovum travels through the ampulla; if unfertilized, the corpus luteum degenerates.

• Uterine (Menstrual) Cycle Phases:

  • Menstrual Phase (Days 1–6): Shedding of endometrial lining.

  • Proliferative Phase (Days 7–14): Endometrial and myometrial thickening driven by estrogen; cervical mucus becomes thin, clear, and elastic (Spinnbarkeit $> 5\,\text{cm}$).

  • Secretory Phase (Days 15–26): Progesterone increases endometrial vascularity and swelling to receive the blastocyst.

  • Ischemic Phase (Days 27–28): Estrogen and progesterone levels drop if implantation does not occur, leading to vascular breakdown.

Gametogenesis and Fertilization

• Cellular Division:

  • Mitosis: Replicates body cells into exact genetic copies for growth and tissue repair.

  • Meiosis: Reduces chromosome numbers by half to create gametes ($23$ chromosomes).

• Gametogenesis:

  • Oogenesis: Produces female ova; all primary ova are present at birth.

  • Spermatogenesis: Produces male sperm; initiates at puberty.

• Fertilization Process:

  • Occurs in the ampulla of the fallopian tube within $12\text{--}24\text{ hours}$ of ovulation (sperm remain viable for $48\text{--}72\text{ hours}$).

  • Union of ovum ($23$ chromosomes) and sperm ($23$ chromosomes) restores the diploid set ($46$ chromosomes / $23$ pairs; $XX$ for female, $XY$ for male).

• Twin Classifications:

  • Dizygotic (Fraternal): Fertilization of two separate ova by two distinct sperm (results in two blastocysts, two amnions, and two chorions).

  • Monozygotic (Identical): Splitting of a single fertilized ovum.

Fetal Development and Structures

• Placental Functions and Structure:

  • Provides nutrition, excretion, oxygenation, immunity, and hormone production (hCG, hPL, progesterone, estrogen).

  • Fetal Side: "Shiny" Schultz.

  • Maternal Side: "Dirty" Duncan.

• Amniotic Fluid:

  • Functions to cushion the fetus, regulate temperature, allow musculoskeletal movement, and promote symmetrical growth.

  • Normal Volume: $700\,\text{mL} - 1000\,\text{mL}$.

  • Hydramnios (Polyhydramnios): $> 2000\,\text{mL}$.

  • Oligohydramnios: $< 400\,\text{mL}$.

  • Amniotic Fluid Index (AFI): Low if $\le 5\,\text{cm}$; high if $\ge 20\,\text{cm}$.

• Umbilical Cord: Contains 2 arteries and 1 vein ($2\text{A}1\text{V}$) encased in Wharton's jelly.

• Fetal Circulation Adaptations: Umbilical vein, ductus venosus, foramen ovale, ductus arteriosus, and umbilical arteries.

• Developmental Timeline:

  • 4 Weeks: Fetal heart begins beating; limb buds and primary lung buds appear.

  • 8 Weeks: All essential organ systems are formed.

  • 8–12 Weeks: Fetal heart rate detectable via Doppler ultrasound.

  • 12 Weeks: Genitals are differentiated; urine is produced; spontaneous movement occurs.

  • 16 Weeks: Biological sex identifiable via ultrasound.

  • 20 Weeks: Fetal heart tones audible with a fetoscope; mother feels movement (quickening); vernix caseosa and lanugo coat the fetus.

  • 24 Weeks: Respiratory movements begin; surfactant production initiates; age of viability reached.

  • 28 Weeks: Eyes open and close; lungs are capable of gas exchange.

  • 32–36 Weeks: Subcutaneous fat accumulates; lanugo begins to diminish.

  • 37–40 Weeks: Term gestation; passive maternal antibody transfer occurs.

Infertility and Assisted Reproduction

• Definition: Inability to conceive after $12\text{ months}$ of regular, unprotected intercourse (affects $15.5\%$ of couples in the US).

• Diagnostic Evaluations:

  • Female: Basal body temperature (BBT), Spinnbarkeit test, hormonal assays (FSH, LH), endometrial biopsy, transvaginal ultrasound.

  • Male: Semen analysis, hormone profile, ductal examination.

• Pharmacological Treatments:

  • Clomiphene citrate (Clomid): Stimulates pituitary release of FSH and LH to induce ovulation.

  • Gonadotropins: Direct stimulation of ovarian follicle development.

  • Metformin / Letrozole: Used in polycystic ovary syndrome (PCOS) related anovulation.

  • Bromocriptine (Parlodel): Treats hyperprolactinemia-induced anovulation.

• Assisted Reproductive Technologies (ART):

  • Intrauterine Insemination (IUI): Direct placement of processed sperm into the uterus.

  • In Vitro Fertilization (IVF): Fertilization occurs in a laboratory setting prior to uterine embryo transfer.

  • Gamete Intrafallopian Transfer (GIFT): Unfertilized ova and sperm are placed directly into the fallopian tube for in vivo fertilization.

  • Zygote Intrafallopian Transfer (ZIFT): Eggs fertilized in vitro are transferred to the fallopian tube at the zygote stage.

  • Tubal Embryo Transfer (TET): Embryos transferred to the fallopian tube at the embryonic stage.

Genetic Disorders and Inheritance

• Genetic Terminology:

  • Karyotype: Visual display of an individual's chromosomes ($22$ pairs of autosomes, $1$ pair of sex chromosomes).

  • Phenotype: Observable physical or clinical traits.

  • Genotype: Underlying genetic structure.

• Chromosomal Conditions:

  • Trisomy 21 (Down Syndrome): $47,XX,+21$ or $47,XY,+21$ ($1\text{ in }700$ live births); features hypotonia, epicanthal folds, simian line, and congenital heart defects.

  • Trisomy 18: ($1\text{ in }3000$ live births); characterized by severe hypotonia, overlapping fingers, and rocker-bottom feet.

  • Turner Syndrome: $45,X$ ($1\text{ in }5000$ live female births); presents with webbed neck, short stature, primary amenorrhea, and aortic coarctation.

  • Klinefelter Syndrome: $47,XXY$ ($1\text{ in }1000$ live male births); presents with gynecomastia, small testes, and decreased fertility.

• Inheritance Patterns:

  • Autosomal Dominant: Affected individuals have a $50\%$ chance of transmitting the condition to each child (e.g., Huntington disease, Polycystic kidney disease, Marfan syndrome).

  • Autosomal Recessive: Two carrier parents have a $25\%$ probability of having an affected child and a $50\%$ probability of having a carrier child per pregnancy (e.g., Cystic fibrosis, Sickle cell anemia, Tay-Sachs disease).