The menstrual cycle Flashcards
Menstrual cycle
refers to the cyclical processes occurring in the female reproductive tract in preparation for pregnancy
Ovary
site of ovulation -egg is produced and is intrinsic to the menstrual cycle ad is the reason that the ovary itself produces hormones
Uterine cavity
site of endometrium and then woman get menstruation which takes it down through cervix to then the vagina
what is the hormonal control of the menstrual cycle dependent on
release of different hormones
4 phases of menstrual cycle
1.menstruation
2.the follicular phase, 3.ovulation
4. the luteal phase.
follicular phase
post menstruation , hypothalamus release gonadotrophin- releasing hormone activates anterior pituitary releasing the stimulating (FSH) and luteinising hormone(LH)
What do the FSH and LH hormones do in the follicular phase?
wake up ovary and produces follicle(dormant egg) one egg will become dominant and supress the others and woman will only stimulate and release egg
folliculogenesis
one of the ovams start to grow and gets the ovary to produce estrogen
Theca cells
express LH receptors throughout the cycle and synthesise androgens which are transported to granulosa cells which take the androgenand stimulate them and turn them into oestrogen.
Granulosa cells
to stop producing other eggs it secrete inhibits to regulate FSH release supress the hormones to ensure only one egg is produced
Oestrogen
secretion by developing follicle promotes rapid proliferation in endometrium and stimulates endometrium
what happens after there is rapid proliferation in endometrium
Creates positive feedback loop-LH production resulting in LH surge which triggers ovulation
Luteal phase- corupus luteum
follicle releases an egg and when follicle releases an egg is supported by. The oestrogen and itself is producing
what happens after follicle releases the egg and produces oestrogen in luteal phase?
starts to produce progesterone which helps endometrium itself to prepare for pregnancy.
Progesterone
maintains that endometrium at thickness and helps it prepare for pregnancy
forms from the remains of the ovulated follicle and promotes endometrium differentiation by secreting- has negative feedback
Menstruation
progesterone stops being produce endometrium sheds away,
fertilization occurs the embryo will begin to implant.
Human chorionic gonadotrophin(hCG)
produced by the embryo which maintains the corpus luteum.
where does the endometrium sit?
Endometrium sits inside the uterus
what 2 layers does the endometrium compose of?
1.base layer: stays same with the cycle
2.functional layer: changes with the menstrual cycle
Endometrium surface epithelium
bit of the apathy of the endometrium that would face into the cavity of the uterus.
Endometrial stroma
spaces in between
endometrial glands
big spaces in between, the glands are big
Secretary phase
baby implants because glands provide the early nutrients to the baby
endometrium cycle 1
- regeneration:Every month the endometrium sheds away and manages to grow without scarring .Stem cells that go to the endometrium sit there and help generate the scar free healing
2 chances of conception
changes oestrogen levels
-consistency of the cervical fluid-to allow sperm to go through
Decidualisation
occurs in response to progesterone-occurs in response to progesterone
what are the 3 things decidualisation change how the endometrium looks`/
-generates these long glands within the endometrium and builds up glycogen(complex sugar) within the endometrium to feed the baby
-formation of these long spiral arteries-babies need blood supply
Stroma: bits between the gland -round cells are ready for everything
-recruitment of immune cells
what are the three things when the fertile window knows the body knows it wants to get pregnant?
1.changes the position of the cervix
2.consistency of the cervical fluid changes -go allow the sperm through
3.body temperature increase-because of progesterone
Implantation
The embryo comes in and fertilisation occurs in the tube and travel down to the uterus and embryo embeds itself within the endometrium
Embryo selection
interplay between the embryo and the endometrium, place the embryo next to endometrial cells and endometrial cells are growing and the individual cells try reach up and grab the embryo
live birth
Genetically normal embryo and endometrial function perfectly
miscarriage
Genetically abnormal embryo endometrium
Recurrent miscarriage
genetically normal embryo but endometrium doesn’t work
Menstruation
during this the functional layer breaks down- which is the top layer of the endometrium breaks away .This causes a influx of matric metallic proteases(enzymes that eat tissue and influx of immune cells which eat away whole functional layer of endometrium which then sheds as blood.
