Contraception Flashcards
Describe the population trend in Canada between 1959 and 2023?
The birth rate in Canada decreased from 116 births per 1000 in 1959 to 10.1 births per 1000 in 2023 (10 fold decrease)
What is the average maternal age at first birth?
30 years old
How does the birth rate in Saskatchewan compare to the national average in 2022?
In 2022, the birth rate in Saskatchewan was 11.9 births per 1000, slightly higher than the national average of 10.1 births per 1000.
What percentage of pregnancies are unplanned?
40-60%
What percentage of unintended pregnancies end in abortion?
50%
Approximately how many individuals have had at least one induced abortion?
1/3 of individuals
What are the four main hormones related to the menstrual cycle?
- FSH
- LH
- Estrogen
- Progesterone
What is the function of GnRH (gonadotropin releasing homone) in menstruation?
GnRH stimulates the pituitary gland to release FSH and LH.
What is the function of FSH in the menstrual cycle?
FSH stimulates the maturation of follicles in the ovaries.
What is the function of estrogen in the menstrual cycle?
Estrogen, predominantly estradiol, stimulates the thickening of the endometrium and suppresses FSH through negative feedback.
What is the function of LH in the menstrual cycle?
LH triggers ovulation 28-32 hours after its levels surge
Describe the role of progesterone in the menstrual cycle
Progesterone, produced by the corpus luteum prepares the endometrium for implantation and signals the hypothalamus and pituitary to stop FSH and LH production through negative feedback.
What is the significance of the corpus luteum in relation to hormones associated with the menstrual cycle?
The corpus luteum produces androgens, estrogen, and progesterone during the luteal phase of the menstrual cycle.
If implantation does not occur, it stops producing progesterone (reducing negative feedback for FSH and LH, resulting in shedding of endometrium lining and menstruation)
What are the two phases of the menstrual cycle?
- Follicular phase (egg development in ovary)
- Luteal phase (egg has left ovary)
How long is the menstrual cycle?
A plurality of menstrual cycles are 28 days long (14 days follicular, 14 days luteal)
Some women may have longer or shorter total cycle, but luteal phase always lasts 14 days the difference is in the follicular phase
Describe the follicular phase of the menstrual cycle
The follicular phase is the first phase of the menstrual cycle, starting from the first day of the period.
- During this phase, a follicle grows and develops (due to the effects of FSH), with one follicle becoming dominant.
- The dominant follicle produces estrogen, which stops menstrual flow and stimulates the thickening of the endometrial lining.
-Additionally, it leads to the production of thin, watery cervical mucus
Describe the luteal phase of the menstrual cycle
The luteal phase is the second half of the menstrual cycle, lasting for approximately 14 days. During this phase, the released ovum travels through the fallopian tubes to the uterus.
What are the different types of contraception?
- Hormonal
- Barrier
- Permanent
- Natural family planning
What are the two main hormones used in hormonal contraceptives?
Estrogen (ethinyl estradiol or estetrol)
Progestins (synthetic hormones that activate progesterone receptors)
What is the mechanism of action for combined hormonal contraceptives?
Combined hormonal contraceptives usually combine ethinyl estradiol and progestins
Estrogen supresses release of FSH (stops ovulation and maturation of eggs in the ovary)
Progestins
- Supress release of LH and FSH (inhibits ovulation)
- Thickens cervical mucus (impedes sperm transport)
- Changes in endometrial lining (not hospitable to implantation)
What are the main three categories of hormonal contraceptives?
- Combined (estrogen + progestin)
- Progestin-only
- Long-acting reversible contraception
What are some types of combined hormonal contraceptives?
- Pill
- Patch
- Ring
What are some types of progestin-only hormonal contraceptives?
- Pill
- Injection
What are some types of long-acting reversible contraception?
- IUS/IUD
- Implant
What is the most common dosing regimen for birth control pills?
They try to mimic the natural menstrual cycle of 28 days. There is often 21 days of hormones and 7 days of placebo pills
What are the differences between three phasic formulations for hormonal contraception?
Monophasic (fixed levels of EE and progestin)
Biphasic (fixed EE levels and increased progestin in 2nd phase)
Triphasic (fixed or variable EE, but increases in all 3 phases)
What are the advantages of continuous hormonal therapy?
- Continuous dosing regimens are more forgiving for missed doses
- May increase effectiveness by reducing time in hormone-free interval
- Reduce the number of periods
How should a contraceptive pill be started?
Most effetcive on Day 1 (first day of period) and taken daily at the same time
If the patient is not starting on Day 1, then use back-up birth control for first 7 days
What is the birth control failure rate for combined pills in the real world?
3-8% (forgetting to take pill, taking pill late)
Why is missing a dose in Week 1 more serious vs. Week 2 or 3?
This is because missing a dose in Week 1 is close to the time when ovulation occurs, in the event that estrogen and progesterone activity was low due to missed dose, unintended ovulation can occur
What should women patients do when they have missed a dose of their birth control pill?
Consider emergency contraceptive, especially in Week 1
The severity of missing a dose is greatest in Week 1, and tapers off in Week 2 and 3
What are the most common side effects associated with starting combined birth control pills?
Breakthrough bleeding (largely due to estrogen component in it only lasts 1-10 days)
- Check for adherence
Breast tenderness
- If lasts longer than the first 3 months, look for other causes
- Change to pill with lower estrogen
Nausea
- Take HS or with food
- Change to pill with lower estrogen
What are some side effects seen with combined birth control that are normally not seen in trials, but seen in practice?
Weight gain
Headache
Mood changes (depression)
Acne
What are the benefits of combined hormonal contraception?
- Simple and effective birth control
- Improve menstrual symptoms and regularity
- Decreases incidences of many woman-specific conditions (endometriosis, ovarian cancer, osteoporosis)
What are the risks of combined hormonal contraceptives?
- Treatment failure (especially if the patient is on 20mcg and missed dose)
- Venous thromboembolism (risk is 2-3x times higher risk, largely due to estrogen, but lower risk for VTE if pregnant)
- MI and stroke (arterial thrombosis)
Which patient profiles that use hormonal contraceptives are especially at risk for blood clots?
Patients who smoke and are over 35 should not use combined hormonal contraceptives (estrogen is responsible for increasing clot risk)
What are some contraindications for combined hormonal contraceptives?
Estrogen is the cause for most contraindications
- Thromboembolic disease
- Ischemic heart disease/stroke
- Known or suspected breast cancer
- Migraine with aura
- Post-partum (wait at least 3-6 weeks bc woman already has a high natural dose of estrogen following birth), can increase VTE risk
What hormones are found in transdermal contraception?
erhinyl estradiol and progestin
When should transdermal contraception be started?
Apply patch on Day 1, if not Day 1 use back-up contraception or avoid sex for 7 days
How should a transdermal contraception patch be applied?
1 patch applied once per week x 3 weeks (rotate site), then no patch for 1 week (HFI)
The patch can be applied to upper arm, buttocks, lower abdomen, upper torso
What are some adverse effects to transdermal contraception?
- Similar to oral hormone contraception
- Local irritation
- Increased spotting i first 2 cycles
- Less effective in patients over 90kg and increased clot risk
What is the brand name for intravaginal contraception?
Nuvarings are a popular choice
How are intravaginal contrecptives inserted?
- Insert anywhere in the vagina between days 1-5 (use backup birth control for 7 days if not started on Day 1)
- Leave in for 3 weeks, remove for 1 week
Whenever a patient has missed a dose from any contraceptive, what is an important question to ask to assess risk?
Have you had unprotected sex in the last 5 days (sperm can last in the vagina for 5 days and still fertilize an egg)
What are some adverse effects associated with intravaginal contraception?
- Similar to oral and transdermal patch
- Vaginitis
- Foreign body sensation/discomfort
What are the storage requirements for Nuvarings?
While at pharmacy, they are stored in the fridge
Patient does not need to refrigerate once Nuvaring has been dispensed
What is the benefit of progestin-only contraceptives?
They are useful in patients who have not been able to tolerate the side effects of estrogen
- Risk of blood clots
- Smoker and over 35yo
- Obese
- Migraine
What are the two main ingredients used in oral progestin-only contraceptives?
Norethindrone 35mcg OD (no HFI)
AND
Drospirenone 4mg OD x 24 days, then 4 placebo pills
What is the mechanism of action for Norethindrone?
Alters cervical mucus and endometrium
How should Norethindrone be dosed most effectively?
Take 35mcg daily at the same time (within 2-3h)
What is the mechanism of action for Drospirenone?
Suppresses ovulation
How should Drospirenone be used most effectively?
Take 4mg daily (more forgiving with timing between doses vs. Norethindrone)
What happens if a Norethindrone dose is missed?
Use back up contraception for 48 hours
What happens if a Drospiredrone dose is missed?
Less serious vs. Norethindrone. Can miss one or two doses, but any more then use back-up contraception for 7 days
What are some adverse effects of progestin-only contraceptives?
- Irregular bleeding
- Headache
- Bloating
- Acne (due to progestin-linked androgenic activity)
- Breast tenderness
What are some contraindications for progestin-only contraceptives?
- Liver disease
- Breast cancer
- Certain drug interactions
What is the active ingredient in injectable contraception?
Medroxyprogesterone 150mg, dosed every 3 months
What is the mechanism of action for injectable contraception?
Prevents ovulation bysupressing LH/FSH surge
Also increases viscosity of cervical mucus
How is injectable contraception used most effectively?
Given IM q 3 months
If injected within Day 1-5, no back-up method
If injected after Day 5, back up method for 3-4 weeks
If injected more than 2 weeks late, perform pregnancy test EC prn, and back up method for contraception
What are the side effects associated with injectable contraceptives?
Unpredictable bleeding in first months
Hormonal associations (acne, headaches, nausea, decreased libido)
Weight gain (2kg)
Delayed return to fertility (average 9 months after shot)
What are the benefits of medroxyprogesterone injectable contraceptives?
- No estrogen (good for smokers, and migraine patients)
- Amenorrhea (in 60% of patients after 12 months of use)
- Less adherence issues because dosing frequqnecy is every 3 months and needs to be done by health professional
What is the difference between IUS and IUDs?
IUS (intrauterine system) contain drug
IUD (intrauterine device) do not contain drug
What is the real life effectiveness of IUS/IUD?
Very good (only 0.6% treatment failure)
Due to long duration of action (replace every 3-10 years depending on product)
What is the mechanism of action for IUDs?
Copper is releases and produces an inflammatory reaction that is toxic to sperm
What is the mechanism of action for IUSs?
Effects are due to release of levonorgesterol (progestin-only)
- Thicken cervical mucus to prevent sperm transport and permeability
- Alters endometrial lining to prevent implantation
- Can supress ovulation in some individuals
Can a patient insert an IUD/IUS insert the device on their own?
No, need trained clinician to insert IUD into the uterus
These devices also need a clinician to be removed safely
What are the adverse effects of IUD/IUSs?
- Increased bleeding and cramping in first few months, but usually subsides
- Pelvic inflammatory disease (less than 1%)
What are some contraindications associated with IUD/IUSs?
- Pregnancy (pregnancy test is given before the device are inserted)
- Breast, cervical, and endometrial cancer
- STI or pelvic infection within 3 months
What drug is in implantable contraception?
Etonogestrel 68mg (rod is implanted into upper arm of non-dominant arm)
The effects of this birth control option lasts up to 3 years
What is the mechanism of action for implantable contraceptives?
Inhibits ovulation
Changes cervical mucous
What is the effectiveness of implantable contraceptives?
99% effective in preventing pregnancy
What is the added benefit of condoms as a contraceptive device?
In addition to preventing pregnancy, they also reduce risk of contracitng STIs
What is the efficacy of condoms?
Lower than hormonal contraceptives (20% real life railure rate)
What are the two types of permanent contraception?
Tubal ligation
Vasectomy
Both are very effective (about 2% failure rate over 10 years)
What is natural family planning?
Some patients may not want to use hormonal/IUD contraceptives
They will avoid having sex during ovulation
How is timing of ovulation tracked in natural family planning?
3 methods:
- Basal body temperature
- Billings method (mucous consistency)
- Calendar method
- Lactation amenorrhea method
What is the basal body temperature method for natural family planning?
Measure changes in basal body temperature
During ovulation, BB temperature increases by at least 0.2*C
After 3 days of elevated BB temperature, fertile period is considered over
What is the Billings method for natural family planning?
Identify fertile period by recognizing change in consistency and volume of cervical mucous
Cervical mucous becomes clearer, slippery and more elastic as ovulation nears
What is the calendar method in natural family planning?
Chart menstrual cycle over 6-12 cycles
Subtract 21 from length of shortest cycle (fertility begins)
Subtract 10 from length of longest cyles (fertility ends)
Avoid having sex during these times in the cycle
What is a potential downfall of the calendar method of natural family planning?
Doesn’t account for shifts in timing of ovulation due to factors like stress and illness
What is the lactational amenorrhea method in natural family planning?
Physiological infertility from breastfeeding caused by hormonal supression of ovulation (reduced suppression after baby is over 6 months)
98% effective
What is emergency contraception?
EC is a form of birth control used after intercourse but before implantation
EC is a woman’s last chance to prevent a pregnancy
What is the definition of pregnancy?
Begins with implantation of fertilized ovum (implantation occurs 6-14 days after fertilization)
What are some indications for emergency contraception?
- Patient is of reproductive age (have had their period)
- Patient does not want to get pregnant
- Patient has had unproteced sex within the past 120 hours (5 days)
When is risk of pregnancy the highest?
It is greatest 5 days before ovulation to 1 day after sex
EC can be offerred at any stage in her period for reassurance
What are some EC options?
Levonorgesterol (OTC)
Ulipristal acetate (pharmacists can prescribe, not OTC)
Combination birth control (Yuzpe method)
Copper IUD
What is the most effective form of emergency contraception?
IUD
Most effective, but there are some accessibility issues. More expensive and need clinician to insert device)
What is the mechanism of action for IUDs as emergency contraceptives?
Prevents implantation by inducing sterile inflammatory reaction in uterus. By-products of inflammation and Cu is toxic to sperm and egg
What are some characteristics of Ulipristal acetate?
- Selective progesterone receptor modulator (delays ovulation by blocking progesterone)
Must be given before LH surge (ovulation)
- Effective for up to 5 days after unprotected sex (no difference in efficacy in the first 5 days)
What are some characteristics of levonorgesterol?
Progestin
Delays ovulation and can inhibit sperm/ova travel
Must be given before LH surge (ovulation)
More effective the earlier it is taken (decreased effect after 3 days following unprotected sex)
Is Uripristal acetate safe in breastfeeding mothers?
UPA is excreted in breastmilk, so discard milk for one week after dose
What is the impact of BMI on emergency contraception treatment?
LNG may be less effective if BMI is above 25
UPA is preferred if patient’s BMI is between 25-30
Copper IUD is preferred if patient’s BMI is above 30
Review slide 93 for review of when to use specific EC agents depending on timing of menstrual cycle
When restarting contraception after EC, what is the processes for levonorgesterol?
- Take same day or next day
- Use back up contraception for 7 days
When restarting contraception after EC, what is the processes for Ulipristal Acetate?
- Wait 5 days after taking UPA
- Use back up contraception for 5+7 (12) days
What are some contraindications for oral emergency contraception?
- No evidence-based contrindications unless patient is pregnant (will need to get medical or surgical abortion)
What is a common abortifacient?
Mifegymiso (Mifepristone + Misoprostol)
Misoprostol is taken 24-48 hours after mifepristone
Accessibility in community pharmacies is an issue
What is Mifepristone?
Progesterone receptor modulator (blocks progestrone binding and promotes uterine wall shedding)
What is the function of Mistoprostol?
Promotes uterine contractions (within a couple of hours after administration)
Does emergency contraception provide protection against STIs?
No protection from STIs, but can use condoms to have safer sex
Can girls under 18 get emergency contracepton?
Yes, girls can recieve EC without parental consent. These girls also have the same level of confidentiality as anyone else
Do pharmacists ever have the duty to report sexual assault?
Not for women over 18, but pharmacists must report the assault of minors
What are the requirements for pharmacists who prescribe contraceptives?
Competency
Environment (most pharmacies have private spaces)
Content (proper education and follow-up)
Review slide 118 for the rules for concientious objection to prescribing contraceptives
What are some good questions to ask before prescribing emergency contraception?
- Date of last menstrual period (evaluate stage of menstrual cycle)
- Time since unprotected sex
- Did any additional unprotected sexual encounter occcur since period
- The individual must consent to taking EC
What are some good questions to ask before prescribing regular hormonal contraception?
- Patient should be at least 12 years old
- Medical history (smoking, anticonvulsansts, bloot clot risk)
- Medication history
- Do they want to become pregnant in the next one year (avoid depo shot if yes)
What are some side effects associated with emergency contraceptives?
Nausea
Vomitting (redose if vomitted with in 2h (LNG) and 3h (UPA))
Breakthrough bleeding (bleeding outside of normal period bleeding, more common in younger patients)
