contraception

see:

• gynaecology
• post-coital emergency contraception
• combined OCP
• progestogens and progesterone-only contraceptives and hormonal Rx
• Sexual Health & Family Planning Australia - handbook on contraception

• unintended pregnancies have a high psychosocial and often financial cost
• most women and their partners, do not consider termination of these pregnancies without enormous psychologic stress at the time or the pregnancy, and later in life in often still raises psychologic issues.
• unintended pregnancy rates in Australia are ~20 per 1000 women aged 15-44 years compared with 17 per 1000 in northern Europe ^{1) 2)}
• ~50% of unintended pregnancies in the US are due to failure of methods which require women to make a decision to use them each day
• adolescents and young adult women are at their most fertile stages of life and at a stage of life when they tend to be less reliable at taking daily contraception or using coital contraceptive methods
• these women in particular should have good access to reliable long acting reversible contraceptive methods (LARC) but uptake in Australia is slow ³⁾
  • a study suggests that if 5% of women in the UK change from using the combined OCP to one of the LARC methods, there would be 7500 fewer unintended pregnancies each year, resulting in a annual net saving cost of almost £10m! ⁴⁾
  • modern methods of LARC are not associated with infertility and are suitable for use in young women, while continuity rates and satisfaction rates are much higher than other methods which suggests lower side effect rates.

• eg. Copper T
• unintended pregnancy rate in 1st year of use 0.6-0.8% ⁵⁾
• if pregnancy occurs, ~50% are ectopic
• usually active for 10 years
• 1yr “very satisfied” rate 66% and 1 year continuation rate 84% ⁶⁾
• RANZCOG guidelines on use of IUCD (pdf)

• unintended pregnancy rate in 1st year of use 0.2% ⁷⁾
• usually active for 5 years
• 1yr “very satisfied” rate 70% and 1 year continuation rate 88% ⁸⁾
• see Mirena intra-uterine device (IUD)

• unintended pregnancy rate in 1st year of use 0.05% ⁹⁾
• etonergestrel subdermal implants last up to 3 years
• 1yr “very satisfied” rate 55% and 1 year continuation rate 83% ¹⁰⁾
• very rarely can migrate in veins to be a foreign body pulmonary embolism¹¹⁾
• eg Implanon
  • does not contain barium sulphate, so will not be visible on plain X-ray
• eg. Implanon NXT/Nexplanon
  • a small, flexible, 4 cm etonogestrel contraceptive rod designed for subdermal insertion in the upper arm
  • contains barium sulphate, making it visible (radiopaque) on plain X-ray

• unintended pregnancy rate in 1st year of use 6% typical use, 0.2% perfect use ¹²⁾
• duration of action usually 3 months
• 1yr “very satisfied” rate 42% and 1 year continuation rate 57% ¹³⁾
• eg. Depo Provera
  • class action against manufacturer Pfizer on claims it may increase the risk of meningiomas - studies suggest it's use increases risk of meningioma by 1.5-5.5 fold, and risk appears to be greatest in those starting over age 31 yr or using it for more than 4 years, and previous studies also link multiple progestins, such as cyproterone acetate (CPA), to meningioma risk ¹⁴⁾

• see combined OCP
• unintended pregnancy rate in 1st year of use 9% typical use, 0.3% perfect use ¹⁵⁾
• 1yr “very satisfied” rate 41% and 1 year continuation rate 55% ¹⁶⁾

• see progestogens and progesterone-only contraceptives and hormonal Rx

• unintended pregnancy rate in 1st year of use 9% typical use, 0.3% perfect use ¹⁷⁾
• 1yr “very satisfied” rate 35% and 1 year continuation rate 49% ¹⁸⁾

• unintended pregnancy rate in 1st year of use 9% typical use, 0.3% perfect use ¹⁹⁾
• 1yr “very satisfied” rate 47% and 1 year continuation rate 54% ²⁰⁾

• see post-coital emergency contraception

• unintended pregnancy rate in 1st year of use 12% typical use, 6% perfect use ²¹⁾

• unintended pregnancy rate in 1st year of use 18% typical use, 2% perfect use ²²⁾

• unintended pregnancy rate in 1st year of use 21% typical use, 5% perfect use ²³⁾

• unintended pregnancy rate in 1st year of use 22% typical use, 4% perfect use ²⁴⁾

• unintended pregnancy rate in 1st year of use 24% typical use, 0.4-5% perfect use ²⁵⁾

• The mechanism of action of hormonal contraceptives and intrauterine contraceptive devices. AmJObGyn. Volume 181(5, Part 1) November 1999  pp 1263-1269
• Female sexual health. Sheila Bryan (RWH). Em. Med. 2003 vol 15: 223-6