Infertility 1 & 2 (Pphysiology and diagnosis) Flashcards
How efficient is the human reproductive system?
Quite inefficient compared to other mammals
Likelihood of conception per cycle is only 20%
And this decreases with age
How long is a ‘normal’ length of time for a couple to try and get pregnant?
For a couple with no underlying pathologies which would affect their ferility…
80% will be pregnant after 12 months of trying
Of the remaining 20% - half of them will be successful by 24 months (so 90% by 24 months)
What are the key factors of conception that need to work in order for it to be successful?
Ovulation
Sperm production
Fertilization
Implantation
What is the diagnostic test used to determine if ovulation is working?
Ovulation happens under the effect of the LH surge that occurs mid-cycle
After ovulation, progesterone increases - progesterone can be measured to determine if ovulation is normal
What hormones drive the process of implantation?
Estrogen and progesterone
Summarise the factors on which natural conception relies on?
(thus the different areas in which stuff can go wrong and lead to infertility)
- Functioning hormonal axis and gonads
- Ovarian reserve
- Regular ovulation
- Normal sperm production
- Fertilization
- egg / sperm interaction
- patent fallopian tubes
- Normal uterine cavity for implantation
What lifestyle factors affect fertility?
Age
BMI
Smoking
Alcohol
Recreational drug use
Stress
What is the clinical definition of infertility?
(this is the useful one for us)
Inability to conceive over a 12 month period despite exposure to regular , unprotected intercourse
This represents a prognosis based approach and provides practical guidance on when to initiate investigations
What is the epidemiological definition of infertility?
Lack of conception after 2 years in women of reproductive age (15-49) who are at risk of becoming pregnant - ie sexually active but not using contraception
What is the demographic definition of infertility?
Inability to become pregnant with a live birth, within 5 years of exposure, based upon a consistent union status, lack of contraceptive use, non-lactation and continuation of a desire for a child.
What percentage of women globally are affected by infertility?
10% of women based on the demographic definition (criteria) of infertility - this is likely an underestimate
What proportion of couples around the world are affected by infertility?
Western countries = 1 in 7 couples
Developing countries = 1 in 4 couples
When do you refer a couple for infertility?
No conception after 1 year of regular, unprotected intercourse
but refer earlier if:
- Age < 35 (woman)
- known cause for infertility
What are the types of infertility?
How common is each type?
Primary - never been able to have/father a child
Secondary - has previously had/fathered a child
Can also be classified by the cause:
- Male cause - 30%
- Female cause - 30%
- Combined - 10%
- Unexplained - 25%
- Other - 5%
What are the main causes of female infertility?
Ovulatory dysfunction 35%
Tubal factors 30%
Diminishing ovarian reserve 20%
Endometriosis 10%
Uterine factors 5%
What are the causes of infertility in men?
Sperm production problems
Problems in producing the hormones
Erection and ejaculation problems
Blockage of sperm transport
When investigating infertility, what tests can determine if eggs are being produced?
Consider age
- decline after 30, steep after 35
Ovarian reserve test:
- Blood test
- FSH level between day 1-5 of cycle or
- AMH level (at any time of cycle)
- Ultrasound scan
- Antral follicular count
In the ovarian reserve test - what blood test values are considered normal?
Which test is more sensitive?
Follicular stimulating hormone (FSH):
- < 10 iu/L
Anti-Mullerian hormone (AMH):
- 5.0-25.0 pmol/L
- More sensitive
When investigating infertility - how can you determine if ovulation is occuring?
Used by couples:
- Natural methods - BBT, Cervical mucus
- LH ovulation kits
- Ovulation calenders
Clinically used:
-
D21 serum progesterone
- any level > 20 nmol/l is suggestive of ovulation
- done 7 days prior to next expected period (so usually 21st day)
When investigating infertility - what test is done to determine if sperm is avaliable?
Semen analysis
When investigating infertility - what factors may determine whether or not the sperm and egg are able to meet?
Intercourse:
- Male problems with erection or ejaculation
- Couples not engaging in intercourse correctly etc
Patency of fallopian tubes
How can we determine the patency of a woman’s fallopian tubes?
What are the indications for each?
Hysterosalpingogram (HSG):
- only if no pelvic infection or gynae problems in past
Laparoscopic dye test
- if they have hx of pelvic infection/gynae problem
How does hysterosalpingograpy work?
A small, fine plastic catheter inserted into the cervix and a dye is injected
This dye tracks up through the fallopian tubes
Xray is taken and the dye shows up - visualising any abnormalities within the reproductive tract
Can also be done using foam and transvaginal USS
Aside from those previously mentioned, what routine tests are done on couples when investigating infertility?
Serum prolactin
Thyroid function test
Chlamydia screening
Pelvic USS
Also check:
- Rubella immunity
- that Cervical smear up to date
