Contraception

Last updated 20.09.12

 

Definition

-  Interventions to the female &/or male prior, during or after sexual intercourse to prevent pregnancy +/- STI

 

Features

-  Effectiveness reported as Pearl Index = number of pregnancies in 100 couples using contraception for 1 year

-  OCP most common in Australia: 60%

-  Male condom 27%

-  IUD <5%

-  Natural <5%

-  Some medications induce hepatic enzmes & decrease effectiveness of contraception

-  Anticonvulsants: COC, OCP, Implanon, Depo-Provera

-  Post partum contraception 

 

Methods

-  Natural

-  Barrier

-  Condoms (male)

-  Condoms (female)

-  Diaphragm

-  Oral Contraceptive Pill (OCP)

-  COC

-  POP

-  Depo-Provera

-  Implanon

-  IUD

-  Mirena

-  Copper

-  Permanent/Sterilisation

-  Tubal Ligation

-  Vasectomy

-  Emergency

 

Advice for Contraception

-  Reason for contraception

-  Family planning: not started, break, finished

-  PMH: DVT, PE, Stroke, AMI, DM, Migraines, smoking

-  Menstrual Hx: may be aggravated by some methods

-  Sexual Hx: need for STI protection

 

WHO Classification of Contraceptive Contraindications

-  WHO 1: no restriction for use of method = always useable

-  WHO 2: advantages outweight risks = broadly useable

-  WHO 3: risks usually outweight benefits = cautious use

-  WHO 4: unacceptable health risk = dont use

 

 

 

Post Partum Contraception

 

Definition

-  Contraception used after completion of pregnancy (post partum)

 

Features

-  Fertility may occur on day 28 post partum+/-

-  Recommended usually 21-28 days post partum

-  Initiate planning antenatally

-  Confirm & instigate immediate post partum

-  50% women low level interest in sex for 3/12+

-  May need to exclude pregnancy prior to insertion

 

Methods

-  Lactational Amenorrhoea

-  Breast feeding: demand feeding, all meals

-  If period has occurred ineffective

-  IUD

-  Suitable in 1st 48hrs post delivery OR after 4/52

-  Else increased risk of spontaneous expulsion

-  Increased risk of perforation (possibly only linear types & not T types ie: Mirena)

-  Screen for endometritis/PID

-  4/52 post partum avoids risk of ?pregnancy

-  6/52 post LUSCS allows adequate scar healing

-  COC

-  Should be avoided due to effect on breast feeding & increased risk of DVT/PE

-  If not breast feeding commence day 21 post partum unless increased risk of DVT/PE ie: obesity, PIH, Pre-eclampsia, LUSCS, >35yrs, multiparous

-  +/- wait until fully mobile & FBE, U&E & LFTs are normal

-  If severe Pre-eclampsia wait 8/52 or alternative contraception

-  POP

-  1st choice hormonal method during lactation

-  Do not effect breast milk

-  Can start immediately but often recommended to commence day 21

-  Depo-Provera

-  Crosses into breast milk

-  If breast feeding wait until 5-6/52 post partum

-  If not breast feeding any time prior to 21 days

-  Implanon

-  If breast feeding wait until 4/52 post partum

-  If not breast feeding day 21 to 28

-  Sterilisation

-  Typically after 12/52+ to allow reconsideration

-  15% women will change mind

-  Allows for potential early death of infant

-  For tubal ligation allows tubes to reduce to normal size for more successful application of clips if used

 

 

 

Natural Contraception

 

Withdrawal/Coitus Interuptus

-  Most common technique in Australia for married couples

-  Withdrawing prior to ejaculation

-  No infective protection

-  Failure rate 27%

 

Lactational Amenorrhoea

-  Breast feeding

-  Commenced immediate post delivery

-  Must be demand feeding ie: all meals

-  If period has occurred since delivery method is ineffective

 

Abstinence

-  Avoidance of sexual intercourse

 

Periodic Abstinence

-  Avoids fertile period of cycle

-  Requires a regular period & highly motivated couple

-  Poor choice as does not permit spontaneous sex

-  Not recommended as places too much effort & therefore stress on couple

-  Calander Method

-  3 days pre & post ovulation unsafe

-  Needs a regular cycle

-  Ovulation Method

-  Testing of cervical mucus to determine ovulation

-  Combined w other methods, BBT & calander method

-  Basal Body Temp (BBT)

-  Used w calander method

-  0.9oC change in temp w ovulation

-  Requires highly motivated couple

 

 

 

Barrier Contraception

 

 

 

Male Condom

-  85-98% effective when used correctly

-  Protection from infection

-  Must be used prior to penetration as pre-ejaculate can contain sperm

 

Cervical Cap/Diaphragm

-  Needs to be fitted at Family Planning Clinic

-  Unsuitable for most of population

-  Left in 6 hrs post intercourse

-  Removed every 24hrs for washing

-  Check regularly for holes

-  Use w spermicide

-  No infective protection

 

Cervical Cap

 

Female Condom

-  Infective protection

-  85-98% effective when used correctly

-  Noisy & uncomfortable

 

Female Condom

 

 

 

Permanent Contraception (Sterilisation)

 

Methods

-  Tubal Ligation

-  Hysterectomy

-  Vasectomy

 

Vasectomy

-  0.1% failure rate

-  Cheaper & safer than Tubal Ligation

-  SFA to confirm azoospermia prior to intercourse

-  Possible to reverse but may create Ab to sperm

 

 

 

References

 

RANZCOG College Statement C-Gyn 11, July 2009

Contraception: Your Questions Answered, John Guillebrand

UK MEC Criteria for Contraception