maternal newborn
FEMALE REPRODUCTIVE SYSTEM
Fallopian Tubes
Each fallopian (uterine) tube is approximately 10 cm in length, extending from near the ovary to the uterus.
Fimbriae (finger-like projections) at the end of each tube draw an ovum into the tube.
Ciliated epithelium within the tube aids in transporting the ovum (or zygote, if fertilized) toward the uterus.
Uterus
The uterus is a muscular organ about 8 cm long and 5 cm wide.
Ligaments help keep the uterus in position, tilted anteriorly over the bladder.
During pregnancy, the uterus significantly increases in size and accommodates the placenta, which nourishes the fetus until birth.
Rising levels of oxytocin stimulate uterine contractions necessary for childbirth.
The uterus comprises three layers:
Perimetrium: the outermost layer.
Myometrium: the muscular middle layer.
Endometrium: the inner mucous membrane, highly vascularized, part of which is shed and regenerated during each menstrual cycle.
During pregnancy, the endometrium contributes to the maternal side of the placenta.
Vagina
The vagina extends from the uterine cervix to the vaginal orifice in the perineum, situated between the urethra and rectum.
After puberty, the vaginal mucosa becomes relatively resistant to infections.
The normal bacterial flora creates an acidic pH that prevents microbial growth.
The hymen, while present, provides mechanical protection.
External Genitalia
Also called the vulva, includes:
Clitoris
Mons pubis
Labia majora and minora
Mammary Glands
Located within the breasts and surrounded by adipose tissue, these glands produce milk following pregnancy.
High levels of estrogen and progesterone during pregnancy prepare the glands for milk production.
Prolactin hormone stimulates milk production post-pregnancy.
Breastfeeding triggers the release of oxytocin, further instigating milk release and uterine contractions.
Ovarian and Menstrual Cycles
Female reproductive cycles are controlled by:
Follicle-stimulating hormone (FSH)
Luteinizing hormone (LH)
Estrogen
Progesterone
These hormones drive changes in ovaries and uterus.
Menstrual Cycle
A menstrual cycle begins with the shedding of the endometrium during menstruation, typically lasting about 5 days.
After menstruation ends, the endometrium proliferates due to estrogen influences, leading to increased secretion of FSH.
Several ovarian follicles begin to develop, although usually only one becomes dominant.
An increase in LH occurs, peaking to induce ovulation.
Post-ovulation, the ruptured follicle transforms into the corpus luteum, which secretes progesterone in addition to estrogen.
Progesterone promotes further endometrial development.
If fertilization does not happen, progesterone levels decrease, resulting in the breakdown of the endometrium and menstruation commencement.
FSH levels increase as estrogen and progesterone levels decline, signaling the start of the cycle anew.
The average menstrual cycle lasts 28 days, with variations possible.
FETAL DEVELOPMENT
Placenta
The placenta functions for metabolic and gas exchange, hormone production, and serves as an endocrine organ.
It produces significant amounts of hCG, progesterone, estrogen, human placental lactogen, and prostaglandins.
Hormones are prominently active during pregnancy, maintaining pregnancy and preparing the body for delivery.
Umbilical Cord
The umbilical cord connects the fetus to the placenta and contains 2 arteries and 1 vein.
The umbilical vein carries oxygenated blood and nutrients to the fetus, while the umbilical arteries carry deoxygenated blood and waste from the fetus to the placenta.
The cord is surrounded by Wharton’s jelly, a gel-like substance preventing compression.
Amniotic Fluid
Amniotic fluid is a clear liquid encapsulating the fetus in the amniotic sac.
It contains electrolytes (sodium, potassium, chloride), proteins, carbohydrates, lipids, hormones, fetal cells, fetal urine, and lung secretions.
In early pregnancy, the fluid is sourced primarily from maternal plasma; as pregnancy progresses, fetal urine becomes the main contributor.
Functions of amniotic fluid include:
Cushioning the fetus from trauma
Maintaining temperature
Facilitating fetal movement (essential for muscle development)
Preventing umbilical cord compression
Aiding in lung development
Normal amniotic fluid is clear, pale yellow, or straw-colored, with no odor or a slightly sweet smell.