Human Fertility and Infertility Flashcards
What are some key points of human fertility?
20% at peak - contraception at cycle
Declines with age
Inefficient reproductive system compared to other mammals
Why does female age matter in human fertility?
Egg count is determined at birth so over lifespan fertility declines as egg number declines
After 40 - fertility is very low
What 4 factors contribute to conception?
Ovulation
Sperm production
Fertilisation
Implantation
What factors need to be working for normal ovulation to happen?
Functioning of hypothalamus, pituitary gland, ovaries and the hormones
Ovulation happens due to LH surge mid cycle and after ovulation progesterone increases
What is the diagnostic test used for ovulation?
Progesterone levels
What are the ovarian and the menstrual cycles?
Ovarian - follicle development
Menstrual - uterine lining development
What factors have to be working for normal sperm production?
Hypothalamus, FSH and LH from anterior pituitary, testes and the outflow tract of the male reproductive system
Describe fertilisation factors
Egg released from ovary then fimbriae end of fallopian tubes pick up the egg
Fertilisation happens in fallopian tube so needs to be patent
Tubal function needs to drive embryo into uterine cavity
Endometrium has to be prepared by oestrogen and progesterone
What does natural conception rely on?
Functioning hormonal axis and gonads
Ovarian reserve
Regular ovulation
Normal sperm production
Fertilisation - egg and sperm interaction and patent fallopian tubes
Normal uterine cavity for implantation
What are lifestyle factors that can affect fertility?
Age, BMI, smoking, alcohol, recreational drugs and stress
What is the clinical definition of infertility?
Inability to conceive over a 12 month period despite exposure to regular unprotected intercourse
Diagnosis provides practical guidance on when to initiate investigation
What are global infertility trends?
1 in 7 couples in western world and 1 in 4 couples in developing countries are affected
When should a couple be referred for fertility problems?
No conception after one year of regular unprotected intercourse
Age over 35 years and if have known cause of infertility get referred earlier
What is primary infertility?
Never managed to have a pregnancy before or the man has never had a child
What is secondary infertility?
Have had a previous child or in a previous relation but can not get pregnanct
What are the infertility causes?
Male - 30%
Female - 30%
Other - 5%
Combined - 10%
Unexplained - 25%
What are the factors for female infertility?
Ovulatory dysfunction
Diminishing ovarian reserve
Endometriosis
Uterine factor
Tubal factor
What are factors for male infertility?
Hormone production
Issue in testicle itself - drugs, varicocele, radiation, heat
Blockage of sperm transport - infection, prostate, vasectomy
Erection and ejaculation problems - prostate surgery, nerve damage, medication
How can infertility be investigated?
Are eggs available, sperm available, can egg and sperm meet and other factors
How can egg reserve be investigated?
Age
Ovarian reserve test - blood test (FSH in day 1 to 5 of cycle and AMH)
US for antral follicular count
How can ovulation be investigated?
Natural - basal body temp (BBT) and cervical mucus
LH ovulation kits
Ovulation calendar
D21 serum progesterone
Describe the natural method of ovulation detection
Measure temperature
As progesterone rises after ovulation, higher temp can be recorded
Mucus discharge is maximum after ovulation
Describe LH Kits
Peak of LH measured mid cycle - urine test
If LH detected then shows positive result
How is ovulation diagnosed?
Progesterone levels taken at appropriate time - day 21 and level are more than 20 nmol/l show ovulation
Describe semen analysis
In sample normal levels are 15 million sperm and 32% having good motility
4% having good morphology
If below then means lower fertility
What are the factors affecting if the egg and sperm can meet?
Intercourse - pain during sex or erection and ejaculation problems
Patent fallopian tubes
How is fallopian tube patency checked?
If no pelvic infection or gynaecological problem in past - HSG hysterosalpingogram
If any - laparoscopic dye test
Describe HSG
Methylene dye is installed by catheter in cervix and an X-ray is taken - contrast shows the fallopian tubes
Can also be done with similar investigation by US
What are other tests for infertility?
Serum prolactin
Thyroid function test
Chlamydia screening
Pelvic US for uterine problems
Rubella immunity and if cervical smear is up to date
