Lecture #3 – Oral and Emergency Contraception



Lecture #3 – Oral and Emergency Contraception

September 19, 2002

Dr. Brown’s new email: tom.brown@utoronto.ca

Amenorrhea

• Can develop when on oral contraceptives like Alesse

• Usually happens over time rather than on very first pack

Side effects of BC pills

1. Amenorrhea

2. Breast tenderness (enlargement)

3. Breast Cancer

4. Nausea

5. Headache

6. Weight gain/bloating

7. Spotting

8. VTE

9. Mood change/libido

1. Amenorrhea

• Develops because not building up endometrial lining

• In some BC pills, you get constant levels of estrogen and progesterone all the time

• The progesterone can continually antagonize the progesterone

• Some individuals do not build enough endometrial tissue in order to get a regular monthly period on the pill

• Not everyone develops it but some may

• No bleeding = no lining (but only if on a BC pill)

Is developing amenorrhea bad?

• Not unhealthy, however it may worry patients

• If develop amenorrhea because of BC pills - it is not bad

• Must warn patient that it is due to the pill and not pregnancy

Management

1. Take previous pill that did not cause the amenorrhea (if pt was on another pill)

2. Give estrogen

• Causes endometrial proliferation

• Can give Premarin 0.625mg 1-21

• eg – In Alesse have a lot of progestin which causes a secretory transformation. When progestin level falls, woman gets a period.

3. Give a higher estrogenic pill

• Eg. Alesse has 20mcg of ethinyl estradiol, therefore can give a pill with 30-35mcg of ethinyl estradiol

• If already on a high estrogenic pill then can give Premarin

2. Breast Tenderness

• Caused by estrogen

• Dose related side effect

• Goes away over time (3-4 months)

• It a patient can put up with the breast tenderness – it will go away

• No medication can alleviate it

• Breast tenderness does not correlate with breast cancer

• Can also be due to enlargement of the breast

Management

o Take a pill with less estrogen content (best method)

o Give it time to go away

o Can restrict caffeine intake

3. Breast cancer

• Controversial

• No definite association between cancer and OCs

• Risk of developing breast cancer for woman by age 35 is 2 in 1000

• This risk gets larger as we get older

• Worst case scenario when taking OCs is 1.5x risk which becomes 3 in 1000

• Risk factor for breast cancer is not having a baby by age 25, therefore since the pill delays pregnancy we don’t know if it is really the pill that is causing the cancer.

4. Nausea

• Due to estrogen

• Goes away with time

Management

o Can take pill with food to decrease the incidence

5. Headache

• OCs can exacerbate headaches

o Don’t want these people on the pill (very strong contraindication)

“Migraine like” headache

o Always occurs in 7 day pill free period

o Therefore it is important to ask patients when their headaches occur

o If it occurs during 7 day pill free interval, then headaches are due to the drop in estrogen

Management

1. Keep taking the pill back to back to 3-4 months

2. Take a pill with less estrogen.

Note – Although estrogen content varies in pills, it is not a significant difference and patient will still get a big drop in estrogen. Therefore this may not work.

3. Give BC pill for 21 days then give Premarin 0.625mg OD x 7 days

o Estrogen doesn’t drop as low

o Patient will still get menstrual period because the progestin still drops and this is what causes the shedding of the endometrium

• Perimenopausal women with fluctuating estrogen levels may also get hot flashes due to the sudden drop in estrogen

o Can give Premarin in this case also

6. Weight gain and bloating

• Mainly due to progesterone content of the pill

Management

o Use a less potent BC pill

o Try a different progestin

▪ Eg Norethindrone to Levonorgestrol

Desogestrel to Ethinoldiol diacetate

▪ People have different side effects with different progestins

7. Spotting

• Common in first 3 months

o 1st month – 25% chance

o 2nd month – 12%

o 3rd month – 10%

• Therefore if patient has spotting, do not make any changes until after 3rd month

Management

o Find out when the spotting occurs

E P

14

o If spotting occurs in first half of cycle (when estrogen high), give a more estrogenic pill

• If estrogen is high in the first half a woman will not spot

o If spotting occurs in the second half of the cycle (when progestin is high), increase the progestational content of the pill

• In practice most just change the pill to something different.

• Pills with the highest amount of spotting are those with low dose steroidal content ie Alesse and Ministran

• If patient is spotting on pills like Marvelon or Ortho-cept which have a higher steroidal dose, do not change to Alesse (low estrogen). Change to a different 30-35mcg pill.

• If spotting occurs after patient has been on pill for years, it may be due to fibroids or hyperplasia

8. Mood

• Change the pill to see if a different progestational agent will have a different effect on mood

9. Libido

• Make sure patient not on a pill that has low androgenic activity, eg – desogestrel, norgestimate and cyproterone acetate

• Make sure patient not on high estrogenic pill since large amounts of estrogen can increase sex hormone binding globulin (SHBG) which ties up testosterone.

Is it safe to use the BC pill in diabetics of hypertensive patients?

• Yes as long as the diabetes and hypertension are controlled.

Breastfeeding

• When woman gives birth she has a high prolactin level which inhibits ovulation

• A woman has amenorrhea after birth due to this high prolactin

• The level of prolactin drops over time and eventually periods will start

• A woman ovulates first and then will have period, therefore, a woman doesn’t know when her period will start again and may need a BC pill to prevent another pregnancy

Is BC pill safe when breastfeeding?

• Estrogen doesn’t get into breast milk in high enough quantities to be harmful to the baby

• Giving increased estrogen after birth will decrease the quantity and quality of milk production

• Rule of thumb: Wait at least 6 weeks and make sure the milk supply is well established

o If mother is having hard time producing enough milk for the infant even after 6 weeks – avoid BC pill

Progestin only pills

Micronor

• minipill

• progestin only (norethindrone acetate)

• take every day with no break

• develop amenorrhea

• primary side effect is spotting

Note:

• there must be a balance somewhere in the endometrium where you get enough estrogen to cause a little proliferation and stabilization of the endometrium but not enough to get shedding.

• Therefore if there is spotting, increase estrogen, not progesterone

Mechanism of action

• Main MOA is not inhibiting ovulation (but can sometimes)

• It increases thick cervical mucous (main MOA)

• It take continuously, can inhibit penetration of the sperm into the cervix

• However, if miss dose by >3hours, the sperm can penetrate through the cervical mucous

• Therefore, very important to take at the same time each day

Main use

• When someone cannot take estrogen

o Eg – Past thromboembolic event

Breastfeeding – doesn’t affect milk supply or quantity

Intolerance to estrogen – increased breast tenderness

• Use for 1 month before begin to get protection

Depo-Provera

• 150mg injection of medroxyprogesterone acetate (MPA)

• given q 12 weeks

Advantage

• convenient

• can use in patients that you don’t want to use estrogen in (ie-past history of VTE)

Disadvantage

1. spotting

• May use Premarin 0.625mg on days 1-21 to prevent (cannot use if CI to estrogen). Only use long enough to stabilize lining, do not use forever.

• Also can shorten interval of injections (give q 8 weeks)

2. Not as reversible as oral contraceptives

• When D/C – 50% people get period back within 6 months

70% within 1 year

90% within 2 years

• Therefore, if want short term contraception, this would not be a good choice.

• Giving injection > 1 week late is equivalent to missing a pill. Therefore if injection occurs >13weeks after previous injection, must do pregnancy test to make sure not pregnant.

3. May cause bone loss and osteoporosis

• Once drug d/c, bone that was lost can be regained. Therefore not permanent effect.

• If used until patient enters peri-menopause, may not get bone back b/c these pts already started to lose bone due to menopause

4. Breast cancer

• Not sure if causes or not

• Will begin to work in 2 weeks (use back up method)

• Contraception on depo-provera is completely reversible even though it takes some time to get period back.

Evra patch

• Contains progestin – metabolite of norgestimate

• Probably has low androgenic activity

• Transdermal patch applied once weekly

Merena IUD

• Has progestin embedded into it

• When use normal IUD, it doesn’t affect menstrual cycle because there is not hormone in it

• Progestin loaded IUD causes amenorrhea (advantage)

Emergency Contraceptive Pill

• Must be used within 72 hours of unprotected intercourse

Unprotected intercourse

1. No contraceptive method

2. Condom breaks

• can break with petroleum bases lubricant

3. Missing >2 pills at any time in cycle

4. Missing 1 pill in first week

5. Greater than 7 day pill free interval

6. Diaphragm removed before 6 hours (must be left for at least 6 hours)

7. Depo-Provera given >13 weeks after previous injection

8. Ejaculation on external genitalia (as Yasser would call it - outercourse)

9. Sexual assault

How does ECP work?

• Primary mechanism is delaying ovulation

A B

P

E

14

A. Line signifies level of E and P in Emergency contraception pill (ECP)

Patient has sex at day 14 (bad time). Pt is given a large amount of E and P at day 14 from ECP. The fall in progestin is not enough to cause a menstrual period because we have endogenous progestin around.

B. If take pill here, progestin level falls and pt will get period because in natural cycle the progestin is low at this time. The ECP did not cause the period. Therefore patient does not need to take the ECP at this time in cycle.

• Therefore if a woman takes ECP and gets period, she didn’t need to take it

• ECP does not cause a period, therefore it does not cause an abortion

• If give to a pregnant woman, it will not cause them to lose the pregnancy nor will it harm the pregnancy.

Other MOAs

• If ovulation has already occurred, the ECP works by other mechanisms

• It may inhibit motility of egg and sperm

• It increases cervical mucous thickness

• It can alter endometrial lining

Contraindications of ECP

• Only 1 absolute CI which is pregnancy

o B/c won’t work if already pregnant and we shouldn’t be prescribing drugs that are known not to work. (however doesn’t harm pregnancy)

• The CIs to estrogen do not apply here because this is a one time high dose only and not chronic high doses of estrogen

Types of ECP

1. Oral medication

• Ovral – E + P

• Plan B – Progestin only

Both used within 72 hours of unprotected intercourse

2. IUD

• Can be used within 5-7 days of unprotected intercourse

• Pt must be a candidate for IUD

• Inconvenient because must see a physician to insert

• MOA – inhibits implantation.

The end!

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