Infertility Flashcards
Definition of infertility
Unable to become pregnancy within 1 year of regular unprotected intercourse
Statistically a couple stands an 80% chance of conceiving within 1 year if:
The woman is <40yo
They do not use contraception
They have regular intercourse
The overall probability increases to 90% if considered over 2 years.
Causes of female infertility
Low Ovarian reserve
Ovulation problems
Structural problems of uterus
Tubal problems
Unexplained
hypothalamic pituitary ovarian dysfunction (predominantly pcos)
Hypothalamic pituitary failure (hypogonadotrophic hypogonadism)
Endocrine disorders
Premature Ovarian Failure
Premature Ovarian Failure
loss of function of the ovaries before the age 40.
Causes of Premature Ovarian Failure
Usually idiopathic
Genetic include Turners syndrome and Fragile X Syndrome
Smoking
Radiation/chemotherapy
Autoimmune disease
High FSH/LH, low oestrogen
General Advice for couples trying to get pregnant
The woman should be taking 400mcg folic acid daily
Aim for a healthy BMI
Avoid smoking and drinking excessive alcohol
Reduce stress as this may negatively affect libido and the relationship
Aim for intercourse every 2 – 3 days
Timed intercourse to coincide with ovulation is not necessary or recommended
Female infertility Investigations
BMI
Chlamydia screening
Semen analysis
Female hormonal testing - AMH,LH FSH, TFTs, prolactin
Rubella immunity in the mother
US
Hysterosalpingogram
laparoscopy and dye
Mx of an Anovulation
BMI related ( decrease if PCOS, increase if low BMI)
moderating their exercise levels if they undertake high levels of exercise.
Clomifene may be used to stimulate ovulation
Letrozole may be used instead of clomifene to stimulate ovulation (aromatase inhibitor with anti-oestrogen effects)
Gonadotropins may be used to stimulate ovulation in women resistant to clomifene
Clomifene MOA
anti-oestrogen (a selective oestrogen receptor modulator). It is given on days 2 to 6 of the menstrual cycle. It stops the negative feedback of oestrogen on the hypothalamus, resulting in a greater release of GnRH and subsequently FSH and LH.
Superovulation/controlled ovarian hyperstimulation
process of inducing a woman to release more than one egg in a month
used for PCOS or PCOS with failed clomiphene
tx is started between days 3 - 5 of the cycle, by daily injection with FSH
monitored by US and blood tests to reduce risk of overstimulation/multiple pregnancy
When the biggest follicle reaches 17mm in diameter, with no more than 2 others of this size, an injection of Human Chorionic Gonadotrophin - HCG is given to induce ovulation with planned intercourse
Mx PCOS for fertility
If BMI over 30, to lose weight
Ovarian drilling
Metformin may be used when there is insulin insensitivity and obesity (usually associated with PCOS)
Advice for Unexplained infertility:
clomifene citrate as a standalone treatment does not increase the chances of a pregnancy or a live birth
Advise them to try sexual intercourse for a total of 2 years (this can include up to 1 year before their fertility investigations) before IVF will be considered.
Factors Affecting Semen Analysis
Hot baths
Tight underwear
Smoking
Alcohol
Raised BMI
Caffeine
Causes of male infertility
hypothalamus/pituitary malfunction (low LH and FSH resulting in low testosterone)
tumours
debilitating illness(hemochromatosis, sarcoidosis, tuberculosis),
syndromes:Kallmann’s, Prader-Willi
latent infection possibly prostatis or urethritis
Testicular damage from:Mumps, orchitis , cancer,Undescended testes, Trauma
Post-Testicular Causes: Ejaculatory duct obstruction, Retrograde ejaculation, Scarring from chlamydia,Absence of the vas deferens eg CF
Male infertility Ix
Hormonal analysis with LH, FSH and testosterone levels
Genetic testing
Further imaging, such as transrectal ultrasound or MRI
Vasography, which involves injecting contrast into the vas deferens and performing xray to assess for obstruction
Testicular biopsy
Mx sperm problems
pulsatile replacement of gonadotropin releasing hormone(GnRH) or injections of gonadotropins(FSH/LH) usually hCG or hMG
correction of an obstruction in the vas deferens
Assisted conception treatment strategies:
IVF: own or donor sperm
Surgical sperm retrieval
is used when there is a blockage somewhere along the vas deferens preventing sperm from reaching the ejaculated semen
Intra-uterine insemination
involves collecting and separating out high-quality sperm, then injecting them directly into the uterus
Intracytoplasmic sperm injection (ICSI)
involves injecting sperm directly into the cytoplasm of an egg, useful when there are significant motility issues, a very low sperm count
Donor insemination with sperm from a donor
IVF
In vitro fertilisation involves fertilising an egg with sperm in a lab, then injecting the resulting embryo into the uterus
Each attempt has a roughly 25 – 30% success rate at producing a live birth.
Steps of IVF
Suppressing the natural menstrual cycle (GnRH)
Ovarian stimulation (FSH)
Oocyte collection (hCG works like LH)
Progesterone is used from the time of oocyte collection until 8 – 10 weeks gestation, usually in the form of vaginal suppositories to mimic corpus luteum role
Insemination / intracytoplasmic sperm injection (ICSI)
Embryo culture
Embryo transfer
A pregnancy test is performed around day 16 after egg collection. When this is positive, implantation has occurred.
Ovarian hyperstimulation syndrome
provoked by the “trigger injection” of hCG 36 hours before oocyte collection.
syndrome presents within 7 days of the hCG injection
increase in vascular endothelial growth factors results in oedema, ascites and hypovolaemia.
Clinical presentation Ovarian hyperstimulation syndrome
Abdominal pain and bloating
N,V,D
Hypotension
Hypovolaemia
Ascites
Pleural effusions
Renal failure
Prothrombotic state
renin level correlates with the severity of the condition
Mx Ovarian hyperstimulation syndrome
Oral fluids
Monitoring of urine output
Low molecular weight heparin (to prevent thromboembolism)
Ascitic fluid removal (paracentesis) if required
IV colloids (e.g. human albumin solution)
