Infertility Flashcards
what is infertility
Infertility is the inability to
conceive and produce viable offspring
what can infertility and subfertility be the result of (2)
◦ Non-infectious causes
◦ Infectious causes
non infectious causes of infertility (10)
◦ Poor bitch breeding management
◦ Irregularities of the estrous cycle
◦ Structural anomalies of reproductive tract
◦ Disorders of sexual development (DSDs)
◦ Ovarian disease
◦ Uterine disease
◦ Hypothyroidism
◦ Systemic disease
◦ Nutrition
◦ Stress
most common cause of infertility/subfertility
Poor bitch breeding management (poor/no ovulation timing)
what are some irregularities of the estrous cycle (6)
◦ Anestrus
◦ Anovulation
◦ “Slow rise” in pre-ovulatory
progesterone levels
◦ Split heat
◦ Persistent estrus
◦ Insufficient luteal phase
persistent estrus; what do you have to distinguish it from, what happens
◦ Important to distinguish from vaginitis
◦ If have cornified vaginal cytology for >30 days without rise in progesterone
◦ Likely have repro tract pathology à secreting hormones
what do you need to distinguish split heat from
◦ Need to distinguish between true split heat & shortened diestral /anestrus phase (4 months inter-estrus interval)
what are three common vaginal structural abnormalities and how do they occur
◦ Vaginal septum
◦ Vaginal circumferential stricture
◦ Hymenal remnants
what can vaginal structural anomalies cause
◦ Vaginitis
◦ Infertility/subfertility (Male cannot penetrate (painful or completely unable), Bitch reactive to natural breeding, Can block sperm transport)
◦ UTIs, urinary incontinence
diagnosis of vaginal structural anomalies
◦ History
◦ Digital palpation
◦ Vaginoscopy
treatment of vaginal septum
◦ If small and can place finger around – can use spay hook with sedation + lidocaine gel
◦ Sometimes too large – has to be done under GA
◦ Want to incise the tissue as cranially as possible
◦ If left inside = issues at whelping = dystocia
what does vaginal hyperplasia occur in response to
estrogen (during proestrus & estrus)
what breeds are predisposed to vaginal hyperplasia
brachycephalic bitches
sequelae of vaginal hyperplasia
◦ 2 nd infections
◦ Self mutilation
◦ Interference with urination
◦ Inability to be bred naturally
reccurrence of vaginal hyperplasia
Can reoccur just prior to whelping as estrogen levels rise again =
obstructive dystocia?
Reoccur at each subsequent heat, usually gets worse at each cycle
how can vaginal hyperplasia subside on its own
Subsides on its own post-ovulation as estrogen levels decrease
treatment of vaginal hyperplasia
◦ Keep mucosa moist – lubricant with panties
◦ Can AI around it (genetics; parturition?)
◦ Surgical removal = reoccurrence
◦ Can induce ovulation if really bad to remove estrogen earlier – can’t breed if this is done
vaginal tumors; names and what are they dependent on
◦ Occasionally hormone dependent
◦ Leiomyomas, leiomyosarcomas
are DSDs common in dogs
yes
examples of DSDs in dogs
os clitoris, Persistent Mullerian Duct Syndrome (PMDS), segmental aplasia of uterus, hypoplastic ovaries, etc.
what breeds have hereditary DSDs
mini schnauzers, cocker spaniels
ovarian vs paraovarian cysts, examples
◦ If within the ovary = ovarian cyst
◦ If adjacent to the ovary = parovarian cyst
◦ Examples: follicular cysts, luteal cysts, etc.
what happens with follicular cysts, dx, treatment
Can secrete estrogen
◦ Persistent estrus
◦ Vulvar swelling, discharge
◦ Other signs of hyperestrogenism
◦ Cornification on estrus smear
Diagnosis: ultrasound
Treatment: OHE, or induce ovulation in valuable breeding bitch – may reoccur
how common is ovarian neoplasia in dogs
overall uncommon
what type of neoplasia can occur on the ovaries and what is the sign
Granulosa cell tumor
◦ Often secretes estrogen
◦ Signs of persistent estrus = as in
follicular cysts
◦ Can also secrete progesterone
◦ Can metastasize
treatment of ovarian disease (neoplasia)
◦ OHE
◦ Chemotherapy if metastatic
◦ Histopathology
diagnosis of ovarian disease (neoplasia)
◦ History & clinical signs
◦ Cornified vaginal epithelium
◦ Ultrasound
clinical signs of ORS
◦ Estrous signs
◦ Pseudopregnancy signs
causes for ORS
Ovarian tissue “left behind” re-vascularizes
◦ Anomalous reproductive anatomy
◦ Surgeon error
◦ Abnormal accessory ovarian tissue
what do you have to differentiate ORS from
Important to distinguish from exogenous hormone exposure
diagnostics for ORS
◦ Estrogen detection = vaginal cytology
◦ Progesterone
◦ LH test
◦ AMH
◦ Abdominal ultrasound
treatment of ORS
◦ Surgery; Risk factors
3 types of uterine disease
-endometritis
-cystic endometerial hyperplasia
-pyometra
diagnosis of endometritis
◦ Vaginal cytology
◦ Endometrial culture, biopsy & cytology
◦ Ultrasound?
treatment of endometritis
-Antibiotics at breeding – controversial – currently debated topic
◦ Need pure culture, heavy growth
does endometritis cause overt clinical disease
nope
what is cystic endometrial hyperplasia (CEH)
progressive disease in non pregnant cycles
Abnormal response to uterine stimulants (estrogen, progesterone, irritants)
what does CEH predispose
to uterine infection -> pyometra
what does CEH cause
fluid accumlation within uterine lumen
what does CEH interfere with
with embryo migration and implantation
when is CEH more common
in older bitches
when does pyometra occur? what is it dependent on?
PROGESTERONE DEPENDENT DISEASE = occurs in diestrus
what is pyometra
Uterine infection = purulent (“pyo”) material present in the uterus
dx of pyometra
◦ Ultrasound
◦ Radiographs
◦ Vaginal cytology
pyometra and CEH
Can occur with or without concurrent CEH
◦ CEH “helps” with the infection= fluid + cysts = a nice home for bacteria
◦ E.coli = most common bacteria cultured
is pyometra a medical emergency?
Constitutes a medical emergency
◦ Can present as lethargic, anorexic, vomiting, PU/PD, +/- vaginal discharge (purulent, red tinged)
open vs closed pyometra
◦ If vaginal discharge present = open pyometra
◦ If vaginal discharge is not present = closed pyometra
what do you see on the CBC in pyometra
Leukocytosis with degenerative left shift (neutrophilia)
surgical treatment of pyometra
-Stabilization with IV fluids, antibiotics
-OHE
medical treatment of pyometra
-Usually only reserved for cases where bitch is not too clinically ill or in cases of open pyometras= valuable breeding bitches
-Aglepristone (EDR) – progesterone receptor blocker (Once cervix opens, if was closed, can give PGF2a)
-Risk of uterine rupture if give PGF2a if cervix is closed
-Antibiotics
-Stabilization (IV fluids, hospitalization)
-Requires rechecks = bloodwork, serial ultrasounds to ensure fluid is draining, progesterone assay
-Need to breed next cycle – likely to happen again – antibiotics during next breeding
what does treatment of pyometra depend upon
need to get rid of progesterone so need to cause luteolysis!
three infectious causes of infertility
◦ Brucella canis
◦ Canine Herpes Virus
◦ Mycoplasma & Ureoplasma
transmission of brucella canis
- Aerosol
- Nose to nose
- Venereal/transplacental
- Contact with any tissues/fluids containing Brucella
what does brucellosis cause
◦ Infertility
◦ EED
◦ Abortion (Late term, Classic time frame = 2 weeks prior to whelping)
◦ Metritis
◦ Neonatal deaths
◦ Prolonged vaginal discharge (post-heat or post- whelp)
what do we see in males with brucellosis
- Orchitis
- Epididymitis
- Scrotal dermatitis
- Prostatitis
what happens in general if a dog has brucellosis
- Generalized lymphadenopathy
- Discospondylitis
- Uveitis
is brucellosis zoonotic
yes!!! super important disease
what causes brucellosis
brucella canis
diagnosis of brucellosis
Serology
◦ Rapid slide agglutination test (RSAT)
◦ Low specificity; high sensitivity
◦ Positives need to be confirmed with further testing
Culture
◦ Intermittent shedding
treatment of brucellosis
◦ Difficult!!!
◦ Life-long infection with intermittent shedding
◦ Neuter/spay + long term antibiotics
◦ In kennel situations = euthanasia of all affected animals is often recommended
should we screen dogs for brucellosis
yes, Screening of breeding animals is recommended
◦ Quarantine all new dogs coming into kennel situation while awaiting test results
what does CHV cause
◦ EED
◦ Abortions
◦ Stillbirths
◦ Neonatal death (Usually acute; largest puppies affected)
diagnosis of CHV
◦ Post mortem, histology of tissues, serology, PCR
how many dogs are exposed to CHV in their life
Most dogs are exposed at some point in their life
◦ Latent infections – shed in the environment
when do problems arise with CHV in dogs
Problem arises when naïve bitches are exposed during pregnancy
◦ Typically once bitch develops immunity = subsequent litters are not affected
treatment for CHV
◦ Typically not rewarding once clinical signs are present
prevention of CHV
◦ Isolation of infected animals
◦ Do not expose 1st time bitches to unknown animals
◦ Optimal hygiene
◦ Warming ambient temperature to over 38C; Virus does not replicate well at high temperatures
commensals of the repro tract that can cause infertility
◦ Mycoplasma, Ureoplasma, E. coli, Enterobacter spp., Streptoccus, Pasteurella, etc
sterilization vs contraception
Sterilization is the permanent
termination of reproduction
Contraception is the temporary suppression of reproduction
when is contraception usually used
◦ Typically used pet animals settings; breeders may ask about this type of
treatment
what is the purpose of sterilization and contraception (3)
◦ Prevention of unwanted pregnancies
◦ Prevention of reproductive pathologies
◦ Prevention of undesired behaviors
why would we use contraceptives in stray animals
◦ Stray dogs/cats = logistics of spay & neuters in these areas can be difficult
◦ Alternative methods aimed at being effective, safe & only needs to be
administered once in animal’s life
surgical sterilization methods (5)
Ovariohysterectomy
Ovariectomy
Hysterectomy (ovary-sparing spay)
Castration
Vasectomy
non surgical sterilization methods (4)
Intra-testicular injection
Immunocontraception
Targeted cytotoxins
Gene silencing
benefits vs adverse effects of spaying prior to 1st heat
Benefits of spay prior to 1st heat
◦ Reduced risk of mammary neoplasia (high rate of metastasis)
◦ Removes risk of pyometra (spay in general)
Adverse effects reported
◦ Cancer
◦ Orthopedic disease
◦ Obesity
◦ Urethral sphincter mechanism incontinence
benefits vs adverse effects of neutering
Benefits of neuter
◦ Removes risk for testicular disease
◦ Reduced risk for prostatic disease
◦ Reduces roaming risk
◦ Reduces undesired behaviors (sometimes)
Adverse effects reported
◦ Cancer
◦ Orthopedic disease
◦ Obesity
general age recommendations for spaying and neutering
◦ Generally = recommend 6 months unless large breed
◦ Female = need to ensure owner knows about substantial increase in mammary neoplasia
◦ Male = can wait for skeletal maturity, but dog must be watched
3 categories of contraception
◦ Steroid hormones
◦ Protein hormones
◦ Contraceptive vaccines
efficacy and reversal of contraception
Efficacy is variable
Reversal is variable
when can we use contraception
Can be used for breeding animals that come into heat before owners want them to, or for those that
cannot undergo surgery for medical reasons, or if owners want a trial of if spay/neuter will change
their behavior
use of progesterone as steroid hormone contraceptive; how does it work? when should it be given? side effects?
- Believed to work by negative feedback loop (decrease gonadotropin concentrations)
- Should only be given during anestrus (when estrogen levels are low)
- Return to estrus expected in 9-12 months, but sometimes can take up to 2-3 years
- Side effects: uterine pathology, mammary tumors, diabetes mellitus, acromegaly, immunosuppression,
increased appetite, weight gain, lethargy, restlessness, alopecia, etc. - Using a low dose, and appropriate timing = potentially less side effect
use of androgens as steroid hormone contraceptive; how does it work, side effects
- Negative feedback loop on LH (suppression of LH surge)
- Return to estrus 1-7 months; used up to 5 years but no studies on return to reproductive function
- Side effects: clitoral hypertrophy, vaginal discharge, vaginitis, male-type behaviors
protein hormone contraceptives; gonadotropin releasing hormone antagonists; flare effect? cost? length of effect?
- Get immediate suppression = no “flare” effect
- Injections, high doses are required.
- Not long lasting, $$$
protein hormone contraceptives; gonadotropin releasing hormone agonists; flare effect? duration? products?
- Initially stimulates gonadotropins (LH & FSH) = estrus induction = “flare” effect (Makes it less desirable as a contraception method)
- Continuous usage = down-regulation of LH & FSH= down-regulation of estrogen, progesterone,
testosterone - Products: deslorelin acetate implants (Suprelorin) – available through (EDR)
- Duration of effects is very variable = 2 products available (6 months and 12 months)
- Suppression usually exceeds these time frames
- Side effects similar to spay/neuter
indications for induction of estrus (2)
◦ Prolonged IEI
◦ Breeding around particular time (stud availability, dog sports/shows)
methods for induction of estrus (4)
◦ Dopamine agonists (cabergoline, bromocriptine)
◦ GnRH agonists (Deslorelin)
◦ Gonadotropins (FSH & LH)
◦ GnRH agonists & gonadotropins = associated with premature luteal failure = pregnancy rates
when is induction of estrus most successful
Most successful when bitches are at least 120 days from previous proestrus
