5.2 Introduction to Contraception Flashcards
What is contraception?
Any method to prevent pregnancy
Blocking transport of sperm
Disruption of HPG axis
Inhibit implantation
What categories can methods of contraception be broadly split into?
Natural Barrier Hormonal Prevention of implantation Sterilisation Emergency
Name three methods of natural contraception
Abstinence
Withdrawal method
Lactational amenorrhoea method
What are three fertility indicators?
Cervical secretions
Basal body temperature
Length of menstrual cycle
What is the principle behind the lactational amenorrhoea method?
Breastfeeding delays return of ovulation after childbirth
Suckling stimulus disrupts release of GnRH
Affects HPG axis
How long is the lactational amenorrhoea method reliable for and what does this rely on?
6 months after giving birth
Exclusive breast feeding
What types of barrier contraception?
Condoms
Diaphragm/Cap
What do low doses of progesterone do in contraception?
Thicken cervical mucus
Does not inhibit LH surge so ovulation still likely
How do contraceptives with high dose of progesterone work?
Inhibit positive feedback of oestrogen
No LH surge
No ovulation
What is the principle action of the COCP?
Prevents ovulation
What are secondary actions of the COCP?
Inhibit implantation
Thicken cervical mucus
Advantages of COCP
Relieve menstrual disorders
Reduced risk of ovarian and endometrial cancer
Disadvantages of COCP
User dependent Interactions with medications Increased risk of breast and cervical cancer Increased risk of MI/stroke No STI protection
What is the principle action of high dose progesterone contraceptives? (Injection and implant)
Prevents ovulation
What are the secondary actions of high dose progesterone contraceptives? (Injection and implant)
Thicken cervical mucus
Prevent endometrial proliferation.
Advantages of progesterone injection
Reliable
Useful for women who can’t have contraception with oestrogen
Disadvantages of progesterone injection
Appointment every 12 weeks
Osteoporosis in low weight patients
Delay in fertility returning
No STI protection
How long does the progesterone implant last for?
3 years
Advantages of progesterone implant
Reliable
LARC
Women who can’t have oestrogen in contraception
Fertility returns quickly
Disadvantage of progesterone implant
Minor procedure
May have unpredictable periods
No STI protection
How should the progesterone only pill be taken?
Every day, without a break
What is the principal action of the progesterone only pill?
Thicken cervical mucus
Which contraceptive pill does not stop ovulation and why?
Progesterone only pill
Because it is low dose progesterone so the LH surge is not inhibited
What are the two types of coil?
Intrauterine system IUS - Progesterone releasing
Intrauterine device IUD - Copper
How long does the IUS work for?
3-5 years
What is the principal action of the IUS?
Prevents implantation
- Reduces endometrial proliferation
What is the secondary action of the IUS?
Thickens cervical mucus
What is the IUD?
Plastic device with added copper
How long is the IUD effective for?
5-10 years
What is the principal action of the IUD?
Copper is toxic to sperm and ovum
What is the secondary action of the IUD?
Endometrial inflammatory reaction
- Prevents implantation
- Changes consistency of cervical mucus
Advantages of the coil
Convenient
Long duration of action
Disadvantages of the coil
Unpleasant insertion Risk of uterine perforation Irregularity in menstruation No protection from STI Displacement
Name for male and female sterilisation
Vasectomy
Tubal ligation/Clipping
How does a vasectomy work?
Vas deferens cut or tied to prevent sperm from entering ejaculate
How does tubal ligation work?
Fallopian tubes cut or blocked to stop ovum travelling from ovary to uterus
Define subfertility
Failure of conception in a couple having regular, unprotected coitus for one year
Difference between primary and secondary infertility
Primary - Never conceived
Secondary - Previously conceived including abortion and ectopic pregnancy
Name the three groups of ovulatory disorders leading to subfertility
Hypothalamic-pituitary failure
Hypothalamic-pituitary-ovarian Dysfunction
Ovarian failure
Broad groups of uterine/peritoneal disorders
Uterine fibroids
Endometriosis
Pelvic inflammatory disease
Causes of tubal damage
Endometriosis Ectopic pregnancy Pelvic surgery Past pelvic infection Mullerian developmental anomaly
How can fertility be increased?
Stop smoking
Reduce alcohol levels
Reduce stress
Healthy diet
Women only- loose weight
Who may be referred to a fertility clinic?
A woman of reproductive age who has not conceived after one year of unprotected vaginal intercourse, in absence of any known cause of infertility
Who may be suitable for an early referral to a fertility clinic?
Women >36yrs
Known clinical cause for infertility
History of predisposing factors for infertility
What are the three main types of treatment for infertility?
Medical treatment to restore fertility
Surgical treatment to restore fertility
ART
