reproduction and contraception Flashcards
laparoscopy
a minimally invasive surgical procedure that allows a surgeon to examine and treat the organs inside the abdomen and pelvis
two main functions of the ovaries
Gametogenesis: oogenesis & folliculogenesis
Steroidogenesis (production
of hormones: Estrogens and
Progesterone)
Oogenesis is the process of creating eggs, or ova, in the female body
sertoli cell and leyding cell function
Sertoli cells provide the environment for germ cells to develop into sperm. They secrete molecules like androgen binding protein (ABP), inhibin B, and activin, which help with spermatogenesis.
leyding cells produce testosterone
spermatogonia
Spermatogonia are stem cells in the testes that produce sperm cells, or spermatozoa, through a process called spermatogenesis
the relevant hormones involved in the ovarian cycle
GnRH(hypothalamus)
LH (pituitary)
FSH (pituitary)
Oestradiol(ovarian cells)
Progesterone(luteal cells)
how many phases of the ovarian cycle are there and what happens during these phases
4
Proliferative phase
After shedding of the endometrial layer during menses, regeneration of the epithelium occurs (luminal epithelium). Estrogens prime/prepares the endometrial epithelial cells (gland regrowth) and stromal cells to proliferate.
ovulation
the luteal phase : here the follicular tissue transforms into the corpus luteum, which is responsible for producing large quantities of progesterone and oestrogen. This suppresses gonadotropin release, thereby restricting further follicular growth
Secretory phase
Early Secretory: Both Progesterone and Estrogens help the cell proliferation and epithelial cell invagination. Glands will start secreting various factors like nutrients, growth factors..etc to improve endometrial receptivity and embryo adhesion. Stromal cells will differentiate into decidualised cells to prepare for embryo support post-implantation.
Late Secretory: if failure of fertilisation (or implantation), drop in estrogens and progesterone leads to spiral arteries constriction (necrosis) and start of endometrial shedding
The endometrium is the tissue that lines the inside of the uterus.
Decidualized cells are cells in the endometrium that support the developing embryo during pregnancy.
Proliferative Phase Ovulation Luteal Phase Secretory Phase (part of the luteal phase), in that order
if the egg produced during ovulation is fertilised, what happens to the corpus luteum
what happens to the corpus luteum if no fertilisation occurs
it is maintained by Human chorionic gonadotropin( hCG)
corpus luteum degenerates after approx. two weeks.
Progesterone and oestrogen levels fall. Results in increase in gonadotrophinlevels and the start of the follicular phase of the next cycle.
spermicides, what they do, and examples
chemical substances that’s used to prevent pregnancy by killing sperm.
Benxalkonium chloride(BZK)
Menfegol
Nonoxynol-9 (N-9)
name some barrier contraceptives
male condom, female condom, diaphragms, cervical caps
what do you know about diaphragms as a contraceptive
Thin, dome-shaped devices made of latex or silicone
it prevents sperm from entering the uterus and is used with spermicide to increase its effectiveness.
Spermicide jelly usually placed inside the dome before insertion
Inserted into the vagina and positioned over the cervix before intercourse, and left in place for 6 hours afterward.
Usually fitted by a physician, but can be inserted or removed by the individual
what do you know about the cervical cap as a contraceptive
Made of soft rubber. can be made of silicone as well, and is placed over the cervix
prevents the sperm from entering the uterus
Spermicidal gel or cream is often used in conjunction with it
The cap needs to remain in place for 6-8 hours after intercourse to ensure that any sperm present are neutralized. It can be worn for up to 48 hours before being removed
Easy to use especially for those people with weak vaginal muscle tone
smaller than the diaphragm, but similar to it
some hormonal contraceptive examples
the oral contraceptive pills
contraceptive injections
implants, inserted under the skin
patches…etc
how do the hormonal contraceptives generally work
they basically consist of various combinations of oestrogen and progesterone that inhibit gonadotrophin secretion.
lead to non-physiological growth of uterine wall.
In addition, progesterone thickens cervical mucus and helps prevent sperm penetration.
two types of intrauterine devices and how they work
hormonal(intrauterine system): releases synthetic progesterone, example levonorgestrel
non hormonal(aka copper coil IUD): releases copper , which is toxic to sperm and ova, thereby preventing fertilisation. it also prevents implantation
difference between progestin and progestrone
Progesterone is a naturally occurring hormone, while progestin is a synthetic chemical that mimics progesterone’s effects
similarities and differenes in both progestin and oestrogen action as contraceptives
ovarian and pituitary inhibition by both
differences
progestin;
thickens cervical mucus whiles oestrogen thins it
endometrial atrophy by progestin, while endometrial proliferation by oestrogen
thickening cervical mucus makes it harder for sperm to reach the uterus.
progestin-only pills and their mode of action
These pills primarily work by thickening the cervical mucus, thereby preventing sperm from entering the uterus
the minipills do not always prevent ovulation, as very low progestin doses are not as consistent as intermediate-high doses
To work effectively, they must be taken at a certain time every 24 hours. Even missing one pill can greatly reduce effectiveness
note that the transdermal patches are as effective as the pills
note that the pill can prevent cancer in the ovaries, endometrium and colon and rectum
two types of emergency contraception
Emergency contraceptive pill – Levonelle or ellaOne (“morning after” pill)
Non-hormonal - Intrauterine device (IUD) – aka copper coil (Cu-IUD)
how levonelle works
contains levonorgestrel (synthetic version of progesterone) which delays ovulation (delays/suppresses LH peak, follicular rupture) – if taken at least 2 days before
leads LH surge
Human implantation & fertilisation unaffected
how ellaOne works
contains ulipristal acetate which delays follicle development , leading to decrease in estradiol levels
it delays ovulation (follicular rupture) by modulating progesterone receptor (represses the expression of progesterone-dependent genes important for ovulation)
Inhibit uterine decidualization and luteal phase endometrial maturation
oestradiol is a form of oestrogen
. Unlike levonorgestrel, ulipristal acetate may have
some effect even after the start of LH surge – inhibited 100% of follicular rupture when taken prior to LH rise
Both levonelle and ellaOne are not effective post-ovulation
both delay ovulation for 5 days
