Female Reproductive Systemm Flashcards
What is oogenesis
Development of ova
(mature unfertilized egg cells)
Oogonia = stem cells in embryo (form ova)
Oogonia multiply and undergo meiosis This stops at prophase I (Primary oocytes)
These remain ‘arrested’ in follicles
until puberty
What happens during oogenis
FSH stimulates follicle growth
↓
Completion of meiosis I and the start of meiosis II
Arrested at metaphase II (Secondary oocyte)
What happens when an egg is penetrated by a sperm?
Completion of 2nd meiotic division triggered
Fertilized egg
(oogenesis complete)
regulation of female reproduction
One ovum released per cycle
-regulation is complex and requires hormones
What hormones are involved in the reproduction in females
-oestrogens(oestradiol)+ progesterone released from the ovary
-luteinixing hormone(LH) + follicle stimulating hormone(FSH) released from anterior pituitary gland
-gonadotropin -releasing hormone released from the hypothalamus
Name the phases of the ovarian cycle
Follicular phase
Ovulation
Lute all phase
Name the phases of the menstrual cycle
Menses
Proliferative phase
Secretory phase
The ovarian cycle
-follicular phase: Several follicles begin to grow
Only one continues to develop, others disintegrate! OESTROGEN dominant
-ovulation: Release of the secondary oocyte
-lute all phase: Follicular tissue remaining in the ovary Release of the secondary oocyte develops into the corpus luteum
PROGESTERONE dominant
Menstrual cycle
Refers to uterine changes
Day 1 of the cycle = 1st day of menstruation
Menstrual flow phase 3 – 7 days
Loss of the functional endometrial layer
↓
Proliferative phase 1 or 2 weeks
Regeneration of the endometrium
↓
Secretory phase 2 weeks
Vascularization and glandular development of the endometrium
Menstrual flow phase
-shedding of the previous endometrium(endometrium shedding)
And the corpus luteum(hormone secreting cells In the ovary
What hormones regulate menses
-LH=acts on thecal cells
-testesterone produced in the Theca acts on the granulosa?
-fsh regulates aromatise expression which is converted to oestradiol via aromatase in granulosa cells
Follicicles in the menses phase
-preantral stage of follicle development
-oocyte surrounded by multiple layers of cells
-layers inward to outward =granulosa,theca,stroma
Follicular phase
Watch lecture
Luteal phase
Watch lecture
Female contraceptive
Watch lecture
Amenorrhea
-Is a menstrual disorder where there is absence of menstruation
-primary amenorrhea is where a girl never had a period age 15+
-secondary amenorrhea is more than 3 consecutive missed periods(previously menstruated)
Normal physiological causes of amenorrhea
-pregnancy
-menopause
-breastfeeding
Oligomenorrhea
-menstrual disorder describing infrequent and inconsistent menstruation
-affects around 14% of those who menstruate at some point and 10-20% of those with fertility
-it is a common feature of PCOS
Normal physiological occurrences of oligomenorrhea
-early menstruation
-postpartum
-perimenopausal women
Causes of primary amenorrhea
-genetic abnormalities eg androgen insensitivity
syndrome causing High testosterone
-impaired hypothalamus or pituitary gland function
-hormone imbalance
-anatomical problems(rarer)
>uterine scarring from c section/fibrosis which results In abnormal endometrium shedding
>blocked reproductive tract(appear to not menstruate)
>missing or abnormal development of reproductive Organs
Influence of lifestyle factors on menstruation
-largely due to impaired hormonal regulation(hypothalamic amenorrhea)
>underweight women’s
>athletes=strenuous activity and restricted diet
>low fat reserves resulting in less adipose tissue resulting in less leptin secretion causing less GNRH release subsequently resulting in delayed or no ovulation and menstruation
-psychological stress which alters hypothalamus-pituitary adrenal(HPA) signalling lowering GNRH
-Drugs
>contraceptives
>cancer chemotherapy and radiotherapy which destroy oestrogen producing cells/follicles
>blood pressure drugs as they can raise prolactin and cause a negative feedback on the hypothalamus
>obesity linked with hypertension causing the increase in oestrogen disrupting the ovarian cycle resulting in oligomenorrhea increasing the risk of miscarriage
PCOS
-effects 6% of pre-menopausal woman
-abnormal hormone levels
>LH and FSH imbalance which interferes with ovulation,can cause oligomenorrhea in most cases or hyperinsulinimia which results In weight gain
>High androgen resulting in enhanced,dysfunctional follicular development causing cyst formation and discrete in functional ovarian reserve(infertility)
Male infertility factors
-poor mobility
-low concentration
-poor morphology
Assisted reproductive techniques
-concentrating sperm and selecting best swimmers
-sperm obtained surgically from the testis/male reproductive tract
-intrauterine insemination(IUI)
-In vitrofertilazation(IVF) hyper -stimulate egg production(hormone therapy)
>oocyte retrieval
>fertilise in vitro
>introduction into the uterus
-Intracytoplasmic sperm injection(ICSI) used for cases with severe lack of sperm mobility
List the compartments of the female reproductive anatomy
-uterus(the womb) A thick muscular organ
lined by the endometrium (rich in blood vessels)
-vagina(the birth canal) receives sperm during copulation
-cervical canal(cervix);neck of the uterus
-external features such as labia and vaginal opening
