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2002 Assisted Reproductive Technology (ART) Report: Introduction
to Fertility Clinic Tables |
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The first table in this section is the
national summary of combined data from all clinics. Individual clinic
tables follow, with each clinic’s data presented in a one-page table
that includes the types of ART used, patient diagnoses, success rates
that each clinic reported and verified for 2002, and individual program
characteristics. Clinics are listed in alphabetical order by state,
city, and clinic name.
Many people considering ART will want to
use this report to find the “best” clinic. However, comparisons between
clinics must be made with caution. Many factors contribute to the
success of an ART procedure. Some factors are related to the training
and experience of the ART clinic and laboratory professionals and the
quality of services they provide. Other factors are related to the
patients themselves, such as their age and the cause of their
infertility. Some clinics may be more willing than others to accept
patients with low chances of success or may specialize in various ART
treatments that attract particular types of patients. These and other
factors to consider when interpreting clinic data are discussed below.
Important
Factors to Consider When Using These Tables to Assess a Clinic
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These statistics are for 2002. Data for cycles started in 2002
could not be published until 2004 because the final outcomes of
pregnancies conceived in December 2002 were not known until October
2003. Additional time was then required to collect and analyze the
data and prepare the report. Many factors that contribute to a
clinic’s success rate may have changed, for better or for worse, in
the 2 years since these procedures were performed. Personnel may be
different. Equipment and training may or may not have been updated. As
a result, success rates for 2002 may differ from current rates.
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No reported success rate is absolute. A clinic’s success rates
will vary from year to year even if all determining factors remain the
same. However, the more cycles that a clinic carries out, the less the
rate is likely to vary. Conversely, clinics that carry out fewer
cycles are likely to have more variability in success rates from year
to year. As an extreme example, if a clinic reports only one ART cycle
in a given category, as is sometimes the case in the data presented
here, the clinic’s success rate in that category would be either 0% or
100%. For further detail, see the explanation
of confidence intervals.
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Some clinics see more than the average number of patients with
difficult infertility problems. Some clinics are willing
to offer ART to most potential users, even those who have a low
probability of success. Others discourage such patients or encourage
them to use donor eggs, a practice that results in higher success
rates among older women. Clinics that accept a higher percentage of
women who previously have had multiple unsuccessful ART cycles will
generally have lower success rates. In contrast, clinics that offer
ART procedures to patients who might have become pregnant with less
technologically advanced treatment will have higher success rates.
A
related issue is that success rates shown in this report are presented
in terms of cycles, as required by law, rather than in terms of women.
As a result, women who had more than one ART cycle in 2002 are
represented in multiple cycles. If a woman who underwent several ART
cycles at a given clinic either never had a successful cycle or had a
successful cycle only after numerous attempts, the clinic’s success
rates would be lowered.
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Cancellation rates affect a clinic’s success rate.
Cancellation rates for cycles using fresh nondonor eggs or embryos
vary among clinics from less than 1% to about 40%. A high cancellation
rate tends to lower the live birth per cycle rate but may increase the
live birth per retrieval rate and the live birth per transfer rate.
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Success rates for unstimulated (or “natural”) cycles are included with
those for stimulated cycles. In an unstimulated cycle, the
woman ovulates naturally rather than through the daily injections used
in stimulated cycles. Unstimulated cycles are less expensive because
they require no daily injections and fewer ultrasounds and blood
tests. However, women who use natural or mild stimulation produce only
one or two follicles, thus reducing the potential number of embryos
for transfer. As a result, unstimulated cycles are less successful,
and clinics that carry out a relatively high proportion of
unstimulated cycles will have lower success rates. Nationally, fewer
than 1% of ART cycles using fresh nondonor eggs or embryos in 2002
were unstimulated. However, in a very few clinics, more than 5% of
cycles were unstimulated.
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Success rates are calculated per cycle rather than per patient.
Therefore, for patients who undergo both fresh and frozen cycles,
success rates are calculated separately for each cycle. Clinics that
have very good live birth rates with frozen embryos would have higher
ART success rates if these births were included as successes from the
original stimulated cycle. Consumers should look at both rates (for
cycles using fresh embryos and for those using frozen embryos) when
assessing a clinic’s success rates.
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The number of embryos transferred varies from
clinic to clinic.
In 2002, the average number of embryos that a clinic transferred to
women younger than age 35 ranged from two to five for fresh–nondonor
cycles. The American Society for Reproductive Medicine and the Society
for Assisted Reproductive Technology discourage the transfer of a
large number of embryos because it increases the likelihood of
multiple gestations. Multiple gestations, in turn, increase both the
probability of premature birth and its related problems and the need
for multifetal pregnancy reductions.
In
addition, success rates can be affected by many other factors, including
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Quality
of eggs.
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Quality
of sperm (including motility and ability to penetrate the egg).
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Skill and
competence of the treatment team.
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General
health of the woman.
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Genetic
factors.
We encourage consumers
considering ART to contact clinics to discuss their specific medical
situations and their potential for success using ART. Because clinics did
not have the opportunity to provide narratives to explain their data,
such conversations could provide additional information to help people
decide whether to use ART.
Although ART offers important
options for the treatment of infertility, the decision to use ART involves
many factors in addition to success rates. Going through repeated ART
cycles requires substantial commitments of time, effort, money, and
emotional energy. Therefore, consumers should carefully examine all
related financial, psychological, and medical issues before begin-ning
treatment. They also will want to consider the location of the clinic, the
counseling and support services available, and the rapport that staff
members have with their patients.
See an explanation of how to read a fertility clinic
table for more information.
Previous ART Reports
Implementation
of the Fertility Clinic Success Rate and Certification Act of 1992
Assisted
Reproductive Technology: Embryo Laboratory
Date last reviewed:
03/23/2006
Content source: Division
of Reproductive Health,
National Center for Chronic Disease
Prevention and Health Promotion
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