Infertility and Contraception Flashcards
How does oestrogen’s feedback change during the menstrual cycle?
Oestrogen has different feedback roles during the menstrual cycle
• Early/middle follicular phase – low oestrogen causing inhibitory effects on the hypothalamus and anterior pituitary
• At ovulation – high oestrogen which causes positive feedback at hypothalamus and anterior pituitary.
How does progesterone affect oestrogen’s feeback
Moderate/High doses of progesterone enhances negative feedback of natural oestrogen causing a reduction of FSH and LH secretion in the follicular phase. It also inhibits the positive feedback of oestrogen in the ovulation phase so there’s no LH surge and no ovulation.
What affect does progesterone have at lower doses?
At lower doses progesterone does not inhibit the LH surge, so ovulation is likely but it will thicken cervical mucus.
Describe how natural contraception works including its advantages, disadvantages?
Natural – use of fertility indicators, no hormones or contraindications but not as effective and unreliable. This is done by measuring cervical secretions, body temperature and length of menstrual cycle. Also, Lactational amenorrhoea method – breast feeding delays the return of ovulation after childbirth but only effective for 6 months
Describe how barrier contraception works including its advantages, disadvantages?
Barrier – physical barrier, preventing entrance of sperm into the cervix. Diaphragm/cap can be inserted any time before intercourse but needs to be used with spermicide. Male female condoms can help prevent STIs but there are allergy risks and female condoms are not as widely available.
Describe how progesterone can be used to prevent ovulation including its secondary actions.
Prevention of Ovulation – progesterone at a moderate or high dose. 3 options COCP combined oral contraceptive pill, progesterone depot and progesterone implant. Progestogen = synthetic form of a progesterone. All progesterone contraception have 2 secondary actions: reduced endometrial receptivity to inhibit implantation and thicken cervical mucus to inhibit penetration of sperm.
What is the combined pill?
Combined Pill – oestrogen and progestogen. Advantages: can relieve menstrual disorders and reduce risk of ovarian cysts and cancer. Disadvantages: user dependant, breakthrough bleeding, breast tenderness, mood disturbance, venous thromboembolism and MI risk and many contraindications.
What is the progesterone depot?
Progesterone Depot – synthetic progestogen injection that lasts 8-13 weeks. Advantages: convenient and can also relieve menstrual disorders. Disadvantages altered and irregular bleeding, delayed return of fertility for up to a year, not quickly reversible and small loss of bone density potentially causing fractures.
What is the progesterone implant?
Progesterone Implant – Advantages long duration of action, convenient and can relieve menstrual disorders. Disadvantages: small procedure required to fit and remove it, local adverse effects and can cause changes in bleeding pattern.
Describe how the progesterone only pill works including its advantages and disadvantages
Using lower doses of progesterone. Progesterone only pill that thicken cervical mucus making it impenetrable to sperm but ovulation is usually not prevented. Advantages: can be used where the COCP is contraindicated but can cause menstrual problems and must be taken at the same time each day within 3 hours.
What is the IUS coil and how does it work
Intrauterine system (IUS lasting 3-5 years) contains progestogen which reduces endometrial proliferation and prevents implantation. Secondary action is to thicken cervical mucus but ovulation is usually not prevented. Advantages: Convenient, long duration and can also relieve menstrual disorders. Disadvantages: insertion may be unpleasant, may become displaced or expulsed, menstrual irregularity and there is a risk of uterine perforation.
What is the IUD coil and how does it work?
Intrauterine Device (IUD lasting 5-10 years) contains copper that is toxic to sperm and ovum, it also causes endometrial inflammatory reaction which prevents implantation and reduced penetration by sperm due to effect of copper on cervical mucus. Advantages: convenient, long duration, can also be used as emergency contraception up to 5 days after intercourse. Disadvantages: insertion may be unpleasant, displacement or expulsion, heavier/longer/more painful periods and risk of uterine perforation.
How do we go about sterilising people and what are the requirements?
Vasectomy – interruption of vas deferens to prevent sperm reaching ejaculate. Performed under local and must be confirmed 12-16 weeks post op. Tubal ligation/clipping – fallopian tubes are cut or clipped and is done under general or local Advantages: permanent and nor hormonal side effects, disadvantages: certain failure rates and should not be chosen if kids in the future is at all possible.
What is the definition of infertility and what are the two types?
Definition – failure of conception in a couple having regular unprotected coitus for one year.
80% of couples will get pregnant after a year of trying
Primary infertility – no previous pregnancy
Secondary infertility – a previous pregnancy
What should you be asking about in a female and male history for infertility?
Female History: Age, duration of infertility, menstrual cycles length, predictability and age of menarche, tubal or pelvic surgery, PID, menorrhagia, pelvic pain and sexual history – infections. Male History: General Health, alcohol/smoking, previous surgery to the testes, drug history, previous infection and sexual dysfunction.
