Session 7- Intro to Contraception Flashcards
what is contraception
any method to prevent pregnancy
what are the three methods to prevent pregnancy
blocking sperm transport to avoid fertilisation
disruption of HPG axis- interfere with ovulation
inhibit implantation of conceptus into endometrium
how do natural fertilty awareness methods work
monitoring and recording fertility indicators throughout menstrual cycle
- cervical secretions and changes in cervix
- basal body temperature
- length of menstrual cycle
what is the lactational amenorrhoea method
breastfeeding after childbirth to avoid pregnancy
delays the return of ovulation by disrupting gonadotrophin release
can be used for up to 6 months postnatally
how do barriers work
examples
provide a physical and/or chemical barrier to sperm entering the cervix
- male/female condoms
- diaphragms
- spermicides
advantages of barriers
STI protection
reliable
diadvantages of barriers
disrupts intercourse
risk of dislodging
how do hormonal birth controls work
examples
interrupt HPG axis and prevent ovulation
- Combined oestrogen and progestogen- COCP
- progesterone only pill- POP
- LARC progestogen depot and implant
what is progestogen
recombinant artificial progesterone
role of progesterone
high levels of progesterone enhance the negative feedback of oestrogen hence
- pre ovulation (reduces FSH and LH)
- inhibit positive feedback of high oestrogen - x LH surge -> x ovulation
what is the effect if lower levels of pregesterone
doesnt inhibiy LH surge -> can still ovulate
will thicken cervical mucus
main action of COCP
prevent ovulation
reducce endometrial receptivity to implantation, thicken cerivial mucus
how is the COCP pill taken
taken for 21 days with a 7 day break OR 21 days + 7 placebo pills
adv of COCP
- reliable
- can relive menstrual disorders
- reduced risk of ovarian and endometrial cancer
- reduced acne in some
disadv of COCP
- user dependant
- no STI protection
- medication interaction
- contraindications -raised BMI migraine and breast cancer
- side effects
- increased risk of CV disease, stroke, VTE breast and cervical cancer
MAIN action of POP
thicken cervical mucus
reduced cilia activity in fallopian tube
doesnt affect ovulatin
adv of POP
reliable
can be used if COCP conraindicated
disadv of POP
no STI protection
strict timing
menstrual irregularities
increased risk of ectopic pregnancy
what is LARC
high fose of progestogen
main action of LARC
inhibit ovulation, thicken cervical mucus and thin endometrial lining
how often do uou have LARC
given intramuscularly every 12 weeks
adv of progestogen
reliable
no known medication interactions
can be used if oestrogen contraindicated and raised BMI
disadv of LARC
no STI protection
not rapidly reversible
menstrual irregularities
what is the progestogen implant
small subcutaneous tube inserted in he arm
