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RECURRENT PREGNANCY LOSS (RPL)
Definitions
- RPL Definition: Two to three consecutive spontaneous
abortions (miscarriages) before 20 weeks gestation.
- Sporadic Abortion: A single pregnancy loss is a
common event occurring in 10-20% of all human pregnancies.
Incidence
- How Many Women Are Affected: Approximately 1-5%
pregnant women have a diagnosis of RPL (40,000 - 200,000 U.S. couples/year).
- What Might Happen After Miscarriage: 49% of women
with two consecutive losses and no live-born children will have a loss
in their next pregnancy, whereas 29% of women with two losses and at
least one live-born child will have a loss in their next pregnancy.
- Is Age a Factor in RPL: The incidence of a single
miscarriage increases with female age in both normal and in RPL patients.
The basic normal miscarriage rate is 10% per pregnancy ages 15-29 and
as high as 55% for women >44 years old. This normal age dependent
increasing miscarriage rate compounds the problem for women with RPL.
POTENTIAL CAUSES OF RPL & DIAGNOSTIC TESTS
The expert team of doctors, embryologists and nurses at RBA are highly
adept at diagnosing, counseling, and treating simple and complex RPL
conditions |
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1. PARENTAL GENETIC ABNORMALITIES
The incidence of chromosomal abnormality in couples experiencing RPL
is 3-5%. Diagnosis is made by chromosome testing (karyotype) of a patient’s
blood sample. Most RPL patients with a chromosome abnormality have no
physical evidence of a problem other than their history of RPL itself.
Couples with a family history of genetic abnormality should be offered
genetic counseling. |
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| Figure 1 - Normal Male Karyotype (46 XY) from husband’s
blood sample |
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Known and suspected types of parental chromosomal abnormalities causing
recurrent pregnancy loss include:
- Translocation - A translocation occurs when
genetic material is exchanged between chromosomes. The translocation
is considered balanced if there is no net loss of genetic material
and unbalanced if some material is lost during the translocation
process. A significant percentage of genetically unbalanced (abnormal)
sperm or eggs will form in translocation carriers. Thus, many adult
translocation carriers will experience RPL and some will deliver
babies with an unbalanced translocation causing mental retardation
or other defects.
- Chromosome inversion - A less common chromosomal
abnormality causing RPL is a chromosome inversion. This involves
reinsertion of a segment of a chromosome in the reverse order following
chromosome breakage. This can lead to duplications or deficiencies
of genetic material during sperm or egg formation. Similar to translocations,
carriers of inversions may produce unbalanced embryos causing RPL
and other defects.
- Single-gene mutations - Mutations in genes required
for embryonic, placental, or cardiac development may result in
RPL. There are no specific tests for these genes now, but completion
of the human genome project has set the stage for this area of
molecular diagnosis.
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| Figure 2 - Female karyotype with abnormal exchange of genetic material
between chromosomes 9:22 (Translocation) |
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- Treatment Options for parental genetic abnormalities
include the following:
- Pre-implantation genetic diagnosis (PGD) in combination
with in vitro fertilization may allow some patients with genetic problems
to conceive their own biological child. Since 1996, RBA scientists
and doctors have achieved successful live-born pregnancies for many
patients with chromosomal abnormalities.
- Donor sperm or donor egg may be appropriate for
some couples with a genetic cause for RPL.
2. UTERINE ANATOMIC ABNORMALITIES
It is estimated that 10-20% of RPL results from
anatomic abnormalities of the uterine cavity. Abnormalities
are diagnosed with an X-ray procedure (hysterosalpingogram - HSG)
or an ultrasound
procedure (sonohysterogram – SHG). Examples include:
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Congenital abnormalities
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Congenital abnormalities probably contribute to RPL
through implantation failure or may cause late losses
in some cases. Although some women can have normal outcomes
with an abnormality in place, it is generally believed
that loss rates approach 70% without correction.
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Septate Uterus - The most common uterine abnormality
causing reproductive loss is the uterine septum.
The septate uterus is corrected by hysteroscopic
septoplasty,
an outpatient surgical procedure. Patients with
a uterine septum have excellent outcomes after
repair with delivery
rates approaching those found in the normal obstetrical
population.
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| Figure 3 - HSG film of septate uterus |
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| Figure 4 - Hysteroscopic Uterine Evaluation |
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| Figure 5 - Uterine Septum Prior to Resection |
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- Less Common Abnormalities:
- Cervical incompetence- Responsible for second trimester fetal
loss, this diagnosis is based on clinical history of very early
rupture of membranes without prior uterine contractions. Cervical
cerclage is the treatment of choice. Occasionally, a surrogate
is required.
- DES exposure- DES (diethylstilbestrol, a synthetic estrogenic
compound) was incorrectly assumed to prevent miscarriage from
the early 1950’s until 1973, when it was banned in the
U.S. Exposure to diethylstilbestrol in uteri may be associated
with RPL in “DES daughters”. DES exposure may result
in T-shaped, unusually small (hypoplastic), or irregularly shaped
uteri, cervical incompetence, ectopic pregnancy, and uterine
constriction (hypoplasia). No good treatment other than surrogacy
or adoption exists for patients with multiple confirmed losses
without any other identifying cause.
- Acquired Uterine Abnormalities
- Myomas (Fibroids)- Fibroids are benign growths that can cause
many reproductive problems, including pregnancy loss. Nonetheless,
it is important to note that not all women with fibroids will
experience reproductive problems. Four basic types of fibroids
exist: pedunculated (on a stalk), subserosal (under the uterine
surface), intramural (in the uterine wall), and submucosal (inside
the uterine cavity). Myomas that distort the uterine cavity (usually
submucus or large intramural types) may cause implantation failure,
resulting from decreased vascularization of the endometrium,
and should be surgically removed in RPL patients. Removal is
accomplished via surgical myomectomy either via inpatient laparotomy
(major surgery) or via outpatient hysteroscopic myomectomy (minor
procedure).
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- Asherman’s syndrome- Scarring inside the
uterus resulting from infection, retained products of conception,
D&C, or previous uterine surgery. Treatment consists of hysteroscopic
surgical correction. Several surgeries may be necessary to achieve
a good result. Outcomes are dependent on the amount of original scar
tissue present. At times, a gestational carrier may be necessary.
- A Note About Gestational Carriers (Third Party Reproduction)
(Surrogacy) – For some patients presenting with a uterine problem,
it is not possible to achieve a successful outcome through surgical
means. Use of a gestational carrier may be recommended in these cases.
Both in-state and out-of-state arrangements are handled on a routine
basis at RBA.
3. HORMONAL & METABOLIC PROBLEMS:
The incidence of endocrine abnormality in women with RPL is approximately
10-15% and may be much higher if patients with PCOS are included. Endocrine
factors may include:
- Hyperprolactinemia – This disorder of pituitary
prolactin oversecretion is usually caused by a small pituitary tumor.
Diagnosis relies on hormonal measurements and exclusion of other causes
of hyperprolactinemia (hypothyroidism, medication use). MRI imaging
of the pituitary will reveal a small benign tumor in the majority of
patients. Elevated prolactin may cause breast milk secretion (70% of
patients), anovulation, and possible luteal phase defect.
- Treatment is directed by the diagnostic work-up
of the disorder. Many patients will undergo therapy with one of
several dopamine agonist medications.
- Thyroid dysfunction- Hypothyroidism is a common disorder
found among reproductive age women. Diagnosis relies on demonstrating
an elevated thyroid stimulating hormone (TSH) level. It is now believed
that very minimal thyroid disease (sub-clinical hypothyroidism) may
cause RPL and pregnancy complications nearly as much as more obvious
thyroid disease.
- Treatment consists of normalizing thyroid function
with thyroid hormone replacement therapy. Ovulatory problems and
the possibility of luteal phase defect may be corrected by thyroid
hormone replacement. Pregnancy loss rates are reduced to near normal
levels when the disorder is corrected. Resolution may take several
months after starting therapy. Calcium replacement with 500-1000mg
supplementation while on thyroid replacement therapy is advised
to lower the risk of osteoporosis during prolonged therapy.
- Diabetes mellitus – Untreated and undiagnosed,
diabetes can cause severe birth defects and RPL. Diabetes is an infrequent
cause of RPL. Normalization of blood sugar control prior to conception
is mandatory.
4. ADVANCED REPRODUCTIVE AGE
Defined as female age of 35 and above. Many women assume that reproductive
success will naturally follow a healthy lifestyle. Unfortunately, living
a healthy life will never change the basic fact that a woman is born with
all the eggs she will ever have. The useful lifespan of human eggs is
slightly more than half the normal human lifespan. Aging eggs have been
subjected to a lifetime of unseen environmental reproductive toxins. A
good number of women with unexplained infertility or RPL are experiencing
accelerated reproductive aging. Aging eggs are more likely to be genetically
abnormal. Thus, advancing female age (and increasing male age in some
cases) will cause an increased number of genetically abnormal embryos.
- Diagnosis is based either on age alone on blood testing
for a “day 3 FSH level” or the “clomid challenge test”,
also known as the “CCCT”. These tests may uncover cases
of abnormal ovarian function or “decreased ovarian reserve”
occurring in women younger than expected. Although some patients with
abnormal FSH test results will conceive on their own, many others require
infertility therapy.
- Elevated day 3 FSH levels and reproductive aging
– Both situations increase the risk of embryonic aneuploidy, adding
to the risk of RPL and lowered pregnancy rates. Our physicians and nurses
have a great deal of experience gained through counseling and treating
the many patients with elevated FSH levels who continue to actively
seek out advice and treatment at RBA.
- Treatment - Patients with “elevated Day 3 FSH”
levels can be treated in one of three ways:
- Ovulation Induction – A woman will normally ovulate one
egg per month during a natural cycle. If this single egg is abnormal,
pregnancy will not occur or will result in a miscarriage. Use of
ovulation induction drugs (clomid or gonadotropins) will generally
increase the monthly egg yield so that a woman may have a better
chance of having multiple eggs available for fertilization. Intrauterine
insemination (IUI) is usually performed to further increase pregnancy
rates. The problem with this therapy, especially in women >35,
is that it relies on random chance to get a “normal egg”
and only assumes (but does not prove) that at least one egg may
be normal. Also, this therapy has not been proven to reduce miscarriage
at all. Problems such as fetal Down’s syndrome cannot be screened
prior to pregnancy as could be done with IVF/PGD.
- IVF using the patient’s own eggs – This technique
is most useful if the resulting embryos can be tested with PGD.
If PGD can be performed, this modality eliminates the majority of
reproductive inefficiencies and allows us to select the best embryos
for placement into the correct location. We are then able to get
beyond some of the random chance issues of other therapies so that
outcomes are enhanced.
- Donor egg IVF - RBA established the first egg donation program
in Georgia in 1992 to serve the needs of patients with high FSH
levels, impending reproductive failure, or actual menopause. Generally,
success rates are much greater than seen with therapies using a
patient’s own eggs.
5. POLYCYSTIC OVARIAN SYNDROME (PCOS)
This disorder of androgen excess, anovulation, and altered insulin metabolism,
“insulin resistance” is associated with up to a 50% miscarriage
rate in patients <35 years old. Older patients may have a higher rate
when the effects of PCOS and age are combined. Typical diagnostic tests
include testosterone and DHEAS levels, fasting insulin/glucose ratio,
FSH and LH levels, and ovarian ultrasound evaluation. Abnormalities, such
as thyroid disease or hyperprolactinemia, should also be excluded. Patients
with significant insulin resistance and high testosterone levels may be
at greatest risk of miscarriage, as are obese patients.
- Treatment consists primarily of inducing ovulation
to generate a pregnancy combined with use of Glucophage (Metformin)
1500mg daily. Use of Metformin has been shown to reduce the high miscarriage
rate seen with PCOS to a level found in the general normal population
(10-15%), if <35 years old.
6. IMMUNOLOGIC CAUSES OF RPL
- It is estimated that less than 5% of RPL is related to immune causes.
There are two basic types of immunologic problems associated with RPL:
- Autoimmune (against self): This refers to the
abnormal immunologic response of the woman to her own tissues. This
response may subsequently carry over to produce RPL. Immune causes
of this type include:
- Antiphospholipid syndrome (APS): Characterized
by significant levels of antiphospholipid antibodies (APA, ACA)
and /or lupus anticoagulant (LAC) and one or more clinical features,
including RPL, intrauterine fetal death or thrombosis. APS is
both an autoimmune and thrombophilic disorder. In general, antibody
levels need to be of the IgG (rarely IgM) subtypes and found in
moderate to high levels to be associated with RPL. APS is the
cause of RPL in five percent of women and is most commonly associated
with second trimester pregnancy loss. It may also cause very early
loss in the form of implantation failure. Five percent of the
normal population of reproductive women may be positive for low
levels of antibodies associated with APS.
- Treatment of + ACA and/or +LAC patients consist
of low- dose aspirin (75-81mg daily), beginning after ovulation
and continued throughout pregnancy, combined with injectible Heparin
5000 units twice a day, usually beginning in the mid-luteal phase
or with a positive pregnancy test. Alternative to Heparin includes
Lovenox 40mg injections once daily.
- Alloimmune Response – an abnormal maternal
immune response to pregnancy tissue (placental or fetal). A pregnancy
has tissue unrelated to the mother that should induce a severe maternal
immune response. Complex mechanisms exist to naturally prevent pregnancy
rejection and problems in this system may occur. However, both investigation
and treatment of these disorders is currently considered to be experimental.
7. LUTEAL PHASE DEFECT (LPD)
LPD is a controversial cause of RPL. This can be a disorder of either
low progesterone production by the ovary or low uterine response to progesterone.
Historically, LPD was diagnosed following out–of–phase endometrial
biopsies in at least two different cycles or by determining low luteal
phase progesterone levels. However, both the endometrial biopsy and progesterone
level testing have been shown to provide highly inconsistent results in
numerous studies. Therefore, physicians oftentimes differ in their diagnostic
evaluation of this disorder. Alternatively, it is entirely appropriate
to not attempt diagnosis at all and proceed with treatments that may potentially
correct a possible LPD.
Treatment primarily consists of inducing ovulation to produce improved
egg production (folliculogenesis) which, in turn, will correct a luteal
phase defect in the majority of patients. Patients may also be administered
progesterone supplementation in addition to ovulation induction.
8. TOXIN EXPOSURE
Toxins such as ionizing radiation, mercury, lead and alcohol are confirmed
teratogens, and could contribute to pregnancy loss. Hyperthermia (fever
or high body temperature during early pregnancy) is a suspected teratogen.
Cigarette smoking has been linked to miscarriage, ovarian damage, diminished
ovarian reserve and possible earlier than expected menopause. The teratogenic
effect of pesticides is unknown. It is doubtful that exposure to food
additives, artificial sweeteners, hair dye, nail polish, and herbicides
contribute to recurrent pregnancy loss. It is advisable to eliminate toxins
at least three months prior to conception.
9. RECURRING EMBRYONIC ANEUPLOIDY
Approximately 50% of couples experiencing RPL have no cause identified
after routine testing. Many of these patients may be experiencing recurring
embryonic genetic abnormalities incompatible with normal survival (aneuploidy).
Examples of this situation frequently treated by RBA physicians include
patients who are referred to us for continued losses despite appropriate
treatment of other non-genetic causes of RPL. A significant number of
these patients were subsequently found to have nearly twice the expected
rate of embryonic genetic abnormality during IVF/PGD. The risk of chromosome
abnormalities (aneuploidy) in embryos increases primarily with female
age, and to a much lower extent, with increasing male age. However, with
the increasing use of IVF/PGD, we have seen very high rates of embryonic
aneuploidy in previously unexplained RPL patients starting as young as
their mid to late 20’s. Thus, recurring embryonic aneuploidy appears
to be a common cause of RPL in patients where no other cause has been
identified regardless of age.
- Diagnosis is accomplished by either testing placental
tissue obtained from an actual pregnancy loss specimen or by generating
early embryos through in vitro fertilization (IVF) and testing one to
two cells from each embryo with preimplantation genetic diagnosis (PGD).
A few select embryos with normal results are then transferred into the
patient’s uterus.
- PGD - Since 1996, RBA has been a national leader
in the field of IVF/PGD applied to many causes, including RPL. A 2004
RBA study with forty RPL patients undergoing PGD uncovered a very high
69.3% embryonic abnormality rate. Nonetheless, a 50% pregnancy rate
was obtained for these high-risk patients (avg age = 35.4 years old)
when two genetically tested embryos were replaced.
10. THROMBOPHILIC DISORDERS (Excessive blood clotting)
Hypercoagulable conditions that are either inherited or acquired may
cause RPL and pregnancy complications. Testing is generally performed
if no other cause of RPL can be identified or if there is a significant
family or personal history of thrombosis or early cerebrovascular events
(stroke). Prior unexplained fetal death (loss of heartbeat after 8 weeks),
severe fetal growth restriction with no other identifiable cause, and
early toxemia (preeclamsia) during pregnancy would be another indication
for testing. Diagnosis is based on blood testing for Factor V Leiden mutation,
Prothrombin gene mutation, Protein C and S deficiency, and hyperhomocysteinemia
(MTHFR mutation).
- Factor V Leiden, Prothrombin Factor II, Protein C&S deficiency,
Antithrombin III deficiency, LAC/ACA - We treat these disorders with
low- dose aspirin and Heparin 5000 units subcutaneously twice a day
(or Lovenox injections 40 mg sq/day). Live-born rates are approximately
70- 80% overall.
- Hyperhomocysteinemia (MTHFR mutation) – Treated with increased
folic acid (2-5 mg daily, vitamin B6, B12 – Folgard Rx) prior
to and during gestation.
11. MALE REPRODUCTIVE ABNORMALITIES
Males with significant, persistent abnormal sperm morphology (abnormal
shape) may father a higher number of genetically abnormal embryos. Diagnosis
requires several semen analyses. We also test sperm with the DNA fragmentation
analysis which may also predict the presence of a higher than average
percent of genetically abnormal sperm. It is possible that some cases
of RPL may be related to increasing male age – particularly in men
over fifty years old.
- Treatment - RBA is one of the few fertility centers
in the U.S. to have a full-time, board-certified male factor reproductive
specialist on staff. Varicocele repair has been shown to improve sperm
morphology but it is uncertain if RPL rates can be diminished as a result
of this corrective procedure. Use of antioxidants and vitamins may also
improve sperm parameters but have not been proven to generate an improved
clinical outcome. A new sperm selection device, the PICSI dish, has
been evaluated at RBA for use during IVF/ICSI. It remains unclear if
it will allow selection of more genetically normal sperm. It also remains
unclear if use of intrauterine insemination (IUI) will select more normal
sperm and subsequently improve pregnancy outcomes in RPL patients with
associated male factor.
12. INFECTIOUS CAUSES OF RPL
- Although maternal infections, such as cytomegalovirus (CMV), toxoplasma,
herpes and rubella have been implicated as causes for single pregnancy
losses, they are not implicated in RPL. The same conclusions apply to
mycoplasma, ureaplasma, syphilis, and listeria infections as causes
of human RPL. Therefore, many physicians may elect to exclude these
tests in the RPL evaluation.
- Bacterial infection within the uterine cavity can be diagnosed with
endometrial biopsy and treated with antibiotics. Oftentimes, a two-week
course of antibiotics are prescribed to RPL patients when no other cause
can be found.
OUTCOMES WITHOUT MEDICAL THERAPY
- Approximately 50% of patients experiencing RPL will have a cause identified
through routine medical testing. A higher percentage of abnormalities
will be detected if IVF/PGD is performed.
- Approximately 70% of couples experiencing RPL will have a liveborn
child without medical therapy. Most of these patients will be < 35
years old.
Benefits of medical therapy:
- Provides assistance to the 30% of couples destined to have a low chance
of a liveborn child without therapy.
- Helps to shorten the time interval to a successful outcome.
- May lower the risk of more losses before a successful outcome.
Psychological Aspects and Support Measures
The physicians and staff at RBA are sensitive to the very unique needs of
our RPL patients. We are here to advise you and to listen to your concerns.
Fully trained psychological counselors are available for you to consult
with as part of your treatment protocol. |

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