maternity

any drug, virus or infections or other exposures that can cause embryonic/fetal development abnormality

during organogenesis, the 1st 8 weeks of gestation

1st day of menstruation and lasts 12-14 days, during this phase the graafian follicle is maturing under the influence of two pituitary hormone: luteinizing hormone (LH) and follicle-stimulating hormone (FSH), the mature graafian follicle produces estrogen

begins when estrogen levels peak and ends with the release of the oocyte (egg) from the mature graafian follicle-referred to as ovulation

• begins after ovulation and lasts approximately 14 days
• -during this phase the cells of the empty follicle undergoes  changes and form into the corpus luteum.

• pertains to the changes in the endometrium of the uterus in responses to the hormonal changes that occur during the ovarian cycle-consists of 3 phases
• -proliferative phase: following mestruation and ends with ovulation, during this phase the endometrium is preparing for implantation by becoming thicker and more vascular-due to the increasing levels of estrogen produced by the graafian follicle.
• -secretory phase: begins after ovulation and ends with onset of mestruation. during this phase the endometrium continues to thicken, primary hormone is progesterone secreted from the corpus luteum.
• -menstrual phase: occurs in response to hormonal changes and results in the sloughing off of the endometrial tissue.

(fertilization) occurs when the sperm nucleus enters the oocyte.

fertilized egg-containing 46 chromosomes (diploid)

single cell zygote undergoes mitotic cell division

when a cell (parent cell) divides and forms 2 daughter cells that contain the same number of chromosomes as the parent cell

3 days after fertilization-16 cell solid sphere

composed of an inner cell mass known as a embryoblast

develops into the embryo and an outer cell mass known as the trophoblast

assists in implantation and becomes part of the placenta

more than one developing embryo such as twins and triplets

identical twins

fraternal twins

embedding of the blastocyte into the endometrium of the uterus-begins around day 5 or 6

progesterone

upper part, posterior wall of the uterus

developing human from time of implantation to 8 weeks

formation and development of body organs-during the critical time of human development

ectoderm (outer layer), mesoderm (middle layer), and endoderm (inner layer)-form the different organs, tissues and body structure of the developing human

3rd gestational week to the 4th week-beats at 4 weeks

week 9-birth (when organ systems are growing and maturing)

develops within the first few weeks of gestation

connects the umbilical vein to the inferior vena cava-allows the majority of the high levels of oxygenated blood to enter the right atrium

opening btwn the right and left atria-blood high in o2 is shunted to the left atrium via the foramen ovale-may take up to 3 months after birth for this to close

connects the pulmonary artery with the descending aorta-the majority of the o2 blood goes to the aorta via the ductus arteriosus and the other little bit of blood goes to the lungs

projections from the chorion that embed into the dicidua basalis and later form the fetal blood vessels of the placenta

• -decidua basalis
• -decidua capsularis
• -decidua vera

the portion directly beneath the blastocyte, forms the maternal portion of the placenta

compartments or lobes of the maternal side of the placenta

metabolic and gas exchange, hormone production (progesterone, estrogen, human chorionic gonadotropin, human placental lactogen)

• -progesterone: facilitates implantation and decreases uterine contractility
• -estrogen: stimulates the enlargement of the breasts and uterus
• -hCG: stimulates corpus luteum so it will continue to secrete estrogen and progesterone, this hormone is detected in preg. tests (rapid increase in 1st trimester then rapid decline)
• -hPL: promotion of fetal growth by regulating glucose available to the developing human, stimulates breast development in preparation for lactation

btwn 8th and 10th week

amnion and chorion

develops from trophoblast

develops from the embryoblast

cushion, prevents adherence, allows freedom of movement, consistent thermal environment

• excess amount of amniotic fluid which increases neural tube disorders, gastrointestinal, cardiac, and chromosomal disorders
• -1,500-2,000 ml

• -decreased amount of amniotic fluid
• - >500 ml
• -because of decrease in placental function
• -newborns will experience congenital renal problems

• 2 arteries-carries deoxygenated blood
• 1 vein- carries oxygenated blood

collagenous substance, protects the vessels of the cord from compression