The Aging Egg: is there any solution? A critical review of causes

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The Spectrum of Ovarian “Aging”:
From birth to menopause
Etiologies and treatment strategies
Amber R. Cooper MD, MSCI
Disclosures
• No relevant financial disclosures
Objectives
• Understand the decline in oocyte quality and
quantity across a woman’s lifespan
• Differentiate between normal and pathologic
ovarian “aging”
• Discuss potential treatment strategies for women
with ovarian “aging” who desire pregnancy
The Ovary
• The human enigma
• Structure discovered
early, normal and
abnormal function
remain elusive
Salvador Dali, 1929
• “Ovarian Aging”
• Natural
• Pathogenic
Natural Ovarian Aging
• Differs from somatic aging (and testicular
aging)
• We tend to focus on the oocyte…but the
follicular unit may be equally important
• Age at menopause has a high heritable
component
•
Twin and Mother/daughter studies
• Individual variability exists in initial follicle pool,
rate of depletion, and age at menopause
Clinical Spectrum of Natural &
Pathologic Ovarian Aging
Recurrent
pregnancy
loss
Fertile
Infertility
Ovarian
aging
Diminished
ovarian
reserve
Primary
ovarian
insufficiency
Early
menopause
Menopause
Oocyte Pool
Quantity vs. Quality
Fixed Pool; peaks at 5-6 mill
80% lost by birth
500,000
Modified from: Speroff. Clinical Gynecologic Endocrinology and Infertility. 7th ed.
25,000
1,000
Declining Oocyte Quantity
 Originally thought to be a simple exponential
decline in number (in the reproductive years)
Mattison DR. Dixon (ed). Reprod Toxicol 1985
Block E. Acta Anat 1952
 Most ultimately believed bi-exponential model of
decline
 Concept of critical mass (25,000)
 Magical age of “37-37.5”
Faddy MJ Hum Reprod 1992
 In reality, more like a constant increasing rate of
loss than a magical number
Hansen K R et al. Hum Reprod 2008
Oocyte Quality = Age
(and maybe a little AMH?)
The Impact of Female Age Alone
(vs. Behavior)
Marital fertility rates by 5-year age
groups in specific populations
ACOG and ASRM Practice Guideline. Fertil Steril 2008
The Impact of Female
Age Alone
•French Study of Female Fecundity
•2193 nulliparous women with azoospermic men
•Donor Inseminations in 11 centers
•Cumulative success rates after 12 cycles
•30 years of age or younger:
74%
•31-35 years old:
61%
•Over 35 years:
54%
Schwartz D, Mayaux MJ. NEJM 1982; 306 (7): 404.
Why does fertility decline with age?
 Ovarian aging ***
 Increased aneuploidy ***
 Endometrial aging
 Behavioral changes
 Increased incidences of other infertility-related
conditions (fibroids, tubal disease, endometriosis,
etc)
 Increased exposure to iatrogenic and
environmental cytotoxic agents
Normal Reproductive Aging
Regular menses does NOT imply normal fertility
Societal and Behavioral
Shifts…
Ovarian
Aging
Reproductive
Delay
Advancing
Technology
Demand
for
“Female
Fertility
Testing”
The term “ovarian reserve”
“Describes a woman’s reproductive potential with
respect to ovarian follicle number and oocyte
quality”
ASRM Practice Committee Aging and Infertility in Women 2006
“A term that is used to determine the capacity of the
ovary to provide eggs that are capable of
fertilization resulting in a healthy and successful
pregnancy”
Wikipedia
Measuring ‘Ovarian Reserve’
Term coined to predict oocyte yield and outcomes
in IVF; Individualize therapies; Not perfect
Serum assays
FSH, Estradiol, Inhibin B
Anti-Müllerian Hormone (AMH)
US measurements
Antral follicle count (AFC)
Ovarian volume
Dynamic Tests
Which population are we
talking about?
All females
Women Delaying
Conception
Infertility
IVF
Antimüllerian Hormone: AMH
• Hot topic of ovarian reserve screens
• Produced by granulosa cells of 2-6 mm follicles
• indirectly reflecting remaining primordial pool
• Seen as the “recruitment regulator”
• Diminishes with age; often undetectable 5+ years
before menopause
• Not cycle day specific
• Beware of assay, storage and handling variability
• Elevated in PCOS patients
• Influenced by BMI and hormonal contraception
Is AMH Nonlinear?
Anti-müllerian
hormone (AMH)
nomogram, based
on a quadratic
model of
log(AMH) on age
Nelson. AMH age nomogram. Fertil Steril 2010.
Antral follicle count (AFC)
Widely used ultrasound measure of
ovarian reserve
Transvaginal, early follicular phase best
studied
Probably the best predictor of ovarian
response to stimulation
Thresholds for a low AFC definition vary
Most use the combined number of 2-9 or
2-10 mm follicles on each ovary
There is an age-related decline in AFC
High AFC may have predictive value
also
10 y/o girl
Abnormal ovarian
aging…
Ovarian Insufficiency
• Probable mechanisms
• Reduced oocyte pool
• Accelerated follicular atresia
• Alterations in follicular processes
** The oocyte is vulnerable in its state of arrest in meiosis I**
• Cumulative exposure ??
Iatrogenic
(Surgery, toxic
therapies
Environmental
(EDC, tobacco)
Autoimmune
Genetic/Epigenetic
• Nuclear
• mtDNA
Idiopathic
Phenotypes of Ovarian Insufficiency
DOR
POI
Cooper AR, Covington SN, Nelson, LM. Primary ovarian insufficiency (POI). In: Santoro N, et. al. ed.
Amenorrhea: A Case-based clinical guide. Humana Press, c2011.
Nelson LM. Clinical practice. Primary ovarian insufficiency. N Engl J Med 2009;360:606-14.
Primary Ovarian Insufficiency
(POI)
 Premature ovarian failure vs Primary ovarian
insufficiency
 Not a dichotomous state
 Much more like a continuum
 Unlike natural menopause Ovarian function is unpredictable
 5-10% may still conceive
 Accelerated physiologic aging or pathologic
reduction through other mechanisms?
Spontaneous POI
 90+% remain idiopathic
 Other etiologies have been proposed
 2% FMR1 premutation (0.7% early menopause; 0.4%
controls)
 4% possible steroidogenic cell autoimmune mechanism
 Abnormal karyotypes
Primary amenorrhea (~10% POI): 50-60%
Secondary amenorrhea: 5-15%
 Other rare genetic mechanisms (e.g. WRN, GALT,
FOXL2)
 10-20% may have familial component
 Associated with autoimmune diseases (thyroid and adrenal)
Nelson L. NEJM 2009
van Kasteren et al Hum Reprod 1999
Murray et at. Genet Med 2014; Voorhuis Hum Reprod 2013
“Diminished ovarian
reserve” (DOR)
• Less severe phenotype than POI or different
pathologic process?
• No clear consensus definition despite hundreds
of publications
Ferraretti et al. Hum Reprod 2011
ESHRE: Defines the poor responder
Need 2 of 3:
(i) advanced maternal age or any other risk
factor for Poor Ovarian Reserve
(ii) a previous POR
(iii) an abnormal ovarian reserve test (ORT).
Using a stricter definition helps create a more crisp
and reliable results from research
Hum Reprod. 2011;The Bologna criteria
Ovarian “responsiveness”
vs “aging”
• Could reduced ovarian “responsiveness” be part
of the aging process?
• Could glycosylation of FSH play a role?
Jiang et al. JCEM 2015
• Or is the ovary itself the master regulator of the
aging process?
X chromosome and Ovarian Aging
 Turner syndrome-ovarian
dysgenesis in 85-90%
 Critical regions
 Xp11.2-22.1
 Xq26-q28; Xq13-q21
 Deletions at/distal to Xq21 usually
secondary amenorrhea/POI
 Smaller deletions Xq27-q28 may
just have early menopause
 Several other candidate genes
Rizzolio et al Hum Reprod 2006 and 2007; Spatz et al Nature Rev 2004
Adapted from Spatz et al. Nature
Reviews 2004
Meiosis is critical to
oocyte development
Adapted from Marston and Amon, Nature Reviews Molec Cell Bio 2005
•
Homologue pairing
and recombination is
vital.
•
Probably-pairing
along the whole X
chromosomes in
order to make viable
oocytes…
•
Examples:
• The mule
• The seedless
watermelon
Genetics of Ovarian Aging
Polygenic and Multifactorial
Complex trait
• Genetic/Heritability
• Environmental
A number of genes throughout the genome have a
suggested role in ovarian function
Past POI studies identified some candidate genes
through FISH/PCR; few through array, linkage, or GWAS
• All small
• Lack power to detect genes with smaller effect sizes
• Most focus on common variants not rare
The Environment and
Ovarian Aging
• Smoking
• 1 to 1.5 years earlier menopause
• Obesity?
• Endocrine disrupting chemicals
• Our recent study found an association between
15 EDCs and earlier menopause; 2-4 years earlier
• 9 PCBs, 3 pesticides, 1 dioxin and 2 phthalates
• Cumulative exposure???
Grindler N, Allsworth J, Macones G, Kannan K, Roehl K,
Cooper AR (2015) PLOS One
Cytotoxic Therapies and
ovarian damage
May be temporary
The majority of past studies focus on the risk of POF/POI
or azoospermia
Many women have diminished ovarian reserve despite
normal menses
Best estimates-risk of infertility
40-80% in females
30-75% in males
Depends on age, cancer site, treatment type and dose
and pretreatment fertility
Lee S et al. J Clin Oncol 2006.; Schover L et al. Cancer 1999.; Sonmezer M and
Oktay. Oncologist 2006.; Wallace W et al. Lancet Oncol 2005.
ASCO guide: Permanent amenorrhea risk
Lee S et al. J Clin Oncol 2006.
Treatment effects on fertility
Ovarian reserve biomarkers have allowed for
further investigation in survivors
Women with childhood cancer therapies show
diminished ovarian reserve despite regular
cycles
AMH and AFC most promising markers
Bath L et al. Hum Reprod 2003.
Larsen et al. Hum Reprod 2003.
AMH in cancer survivors:
Dose-dependent decline
Gracia et al. Fertil Steril 2012.
Can we intervene?
Intervention vs Prevention
• Awareness is key!!!
• Understanding the etiologies is the first step towards
prevention
• Need for better diagnostic tests to intervene prior to
cessation of function
•Fertility preservation options at an earlier age
Nutrition and Ovarian Aging
• Diet
• Composition (fat/carbs)
• Omega 6:3 fats ratio
• Caffeine
• Antioxidants
• Obesity?
• Alcohol, Tobacco
• Exercise/Relaxation
• Supplements
• Environmental exposures…
Oxidative stress
•
Reproductive aging associated with oxidative stress
•
Sources vary: illness, inflammation, smoking, alcohol,
other processes, ?obesity/diet
•
May damage an already fragile aging oocyte or alter the
follicular quality
•
In turn may affect fertilization and embryo growth
processes
•
Antioxidants: Vitamins (A, C, E), nuts/seeds,
fruits/vegetables (5+ servings), herbs (ginger, tumeric,
cloves, cinnamon, oregano)
•
Recent Cochrane review would suggest data still lacking and poor
DHEA
• Metabolic intermediate Androgen
Estrogen
•
Intrafollicular IGF-1 (potentiates gonadotropins?)
•
Own biologic affect?
• Possibly improves oocyte quality, LBR in poor
responders
• DHEA(S) levels decline with age
• JCEM 2013 RCT (China): 16 weeks 25 mg TID in
POI patients (vs placebo), AMH primary outcome
• Kara 2014: DHEA 12 weeks RCT IVF ICSI
showed no increased preg rate.
Casson 2005, Wiser 2010, Yeung et al 2013 JCEM; Kara
2014Eur J Ostet Gynecol Reprod Biol
Co-enzyme Q10
• Important for cell energetics (mitochondrial)
• Antioxidant
• Past “youth drug” used in many subspecialties
• Oocyte energetics
Embryo quality
• Study: Patients with more CoQ10 in follicular
fluid at the time of IVF-more mature oocytes
and better quality embryos (Turi et al; 2012)
• Less aneuploidy too? (Casper’s data)
• Best estimate: 600 mg/day
Oocyte/Follicle development
(not really a “monthly” process)
Antral follicle
recruitment
Gougeon. Hum Reprod 1986
Other supplements
• Myo-inositol (B-complex vitamin)
• Myo + Melatonin antioxidant combo?
• L-arginine amino acid? Mixed data
• Vitamin D deficiencies and IVF?
• Selenium?
• Media supplements or patient diet?
• Most stopped at retrieval, Duration needed for
use to see effect unclear
Ovarian aging and
Tailored IVF Protocols
• Priming with OCPs?
• Less drug and days of FSH?
• Priming with Estradiol?
• Decreased cancellation? More oocytes?
Increased PR?
• Priming with Testosterone?
• Increased sensitivity to FSH, oocytes, IR,
PR, LBR?
Ovarian aging and
Tailored IVF Protocols
• Stimulation regimen
• Antagonist better? Or most equal?
• “Mild” or “Mini” IVF-cost effective and patient
friendly but data on benefit still lacking
• Adding GH? …May be value; meta-analyses
show co-treatment improves outcome (PR/LBR);
? Quality or endometrial improvement rather than
response
Ovarian aging and
Tailored IVF Protocols
• Oocyte retrieval
•
Delaying hCG trigger 0.5-1 hour?
Reichman DE et al. Fertil Steril 2011
• FSH “boost” with hCG ?
Lamb JD et al. Fertil Steril 2011
• Aneuploid screening?
• Time-lapse photography?
Future Intervention?
Experimental options:
Ovarian fragmentation / In vitro
activation study; Kawamura et al
Ovascience technology
Augment; Ovature/OvaPrime
“Ovarian Age” =
AGE +
Ovarian Reserve
(oocyte quantity)
“Reproductive Age” =
Genetics
(Epigenetics)
AGE +
Environment
Transcriptome
Ovarian Health
THANK YOU!
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