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2006 Assisted Reproductive Technology (ART) Report: Section 4—ART
Cycles Using Donor Eggs |
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Are older women undergoing ART more likely to use donor
eggs or embryos?
As shown in
Figures 14–16,
eggs produced by women in older age groups form embryos that are less
likely to implant and more likely to result in miscarriage if they do
implant. As a result, ART using donor eggs is much more common among
older women than among younger women. Donor eggs or embryos were used in
approximately 12% of all ART cycles carried out in 2006 (16,976 cycles).
Figure 44
shows the percentage of ART cycles using donor eggs in 2006 according to
the woman’s age. Few women younger than age 39 used donor eggs; however,
the percentage of cycles carried out with donor eggs increased sharply
starting at age 39. Among women older than age 47, for example, about
89% of all ART cycles used donor eggs.
Figure 44: Percentage of
ART Cycles Using Donor Eggs, by ART Patient’s Age, 2006.
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Do success rates differ by age for women who used ART
with donor eggs compared with women who used ART with their own eggs?
Figure 45 compares
percentages of transfers resulting in live births for ART cycles using
fresh embryos from donor eggs with those for ART cycles using a
woman’s own eggs, among women of different ages. The likelihood of a
fertilized egg implanting is related to the age of the woman who
produced the egg. Thus, the percentage of transfers resulting in live
births for cycles using embryos from women’s own eggs declines as women
get older. In contrast, since egg donors are typically in their 20s or
early 30s, the percentage of transfers resulting in live births for
cycles using embryos from donor eggs remained consistently high at above
40%.
Figure 45: Percentages of
Transfers That Resulted in Live Births for ART Cycles Using Fresh
Embryos from Own and Donor Eggs, by ART Patient’s Age, 2006.
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How successful is ART when donor eggs are used?
Figure 46
shows percentages of transfers resulting in live births and singleton live
births for ART cycles using fresh embryos from donor eggs among women of
different ages. For all ages, the percentage of transfers resulting in
singleton live births (average 33%) was lower than the percentage of
transfers resulting in live births (average 54%). Singleton live births are
an important measure of success because they have a much lower risk than
multiple-infant births for adverse infant health outcomes, including
prematurity, low birth weight, disability, and death.
Figure 46: Percentages of
Transfers That Resulted in Live Births and Singleton Live Births for ART
Cycles Using Fresh Embryos from Donor Eggs, by ART Patient’s Age, 2006.
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What is the risk of having a multiple-fetus pregnancy or
multiple-infant live birth from an ART cycle using fresh donor eggs?
Multiple-infant births are associated with greater
problems for both mothers and infants, including higher rates of
caesarean section, prematurity, low birth weight, and infant disability
or death.
Part A of Figure 47
shows that among the 6,315 pregnancies that resulted from ART cycles
using fresh embryos from donor eggs, about 54% were singleton
pregnancies, about 37% were twins, and nearly 4% were triplets or more.
About 5% of pregnancies ended in miscarriage before the number of
fetuses could be accurately determined. Therefore, the percentage of
pregnancies
with more than one fetus might have been higher than what was reported
(about 41%).
In 2006, 5,393 pregnancies from ART cycles that used
fresh embryos from donor eggs resulted in live births. Part B of Figure 47 shows that 39% of these live births produced more than one infant. This
compares with a multiple-infant birth rate of slightly more than 3% in
the general population.
Although the total rates for multiples were similar for
pregnancies and live births, there were more triplet-or-more pregnancies
than births. Triplet-or-more pregnancies may be reduced to twins or
singletons by the time of birth. This can happen naturally (e.g., fetal
death), or a woman and her doctor may decide to reduce the number of
fetuses using a procedure called multifetal pregnancy reduction. CDC
does not collect information on multifetal pregnancy reductions.
Figure 47: Risks of Having
Multiple-Fetus Pregnancy and Multiple-Infant Live Birth from ART Cycles
Using Fresh Embryos from Donor Eggs, 2006.
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How do success rates differ between women who use frozen
donor embryos and those who use fresh donor embryos?
Figure 48 shows that the success rates resulting from the transfer
of frozen donor embryos were substantially lower than the success rates
resulting from the transfer of fresh donor embryos. This is similar to
the findings for frozen nondonor embryos (see Figure 42).
The average number of embryos transferred was similar for cycles using
frozen donor embryos and those using fresh donor embryos. (See the
national summary table
for information on the average number of embryos transferred for these
cycles.)
Figure 48:
Success Rates for ART Cycles Using Frozen Donor and Fresh Donor Embryos,
2006.
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Section
1 | Section 2 |
Section
3 | Section 4 |
Section
5
Previous ART Reports
Implementation of the Fertility
Clinic Success Rate and Certification Act of 1992 Page last reviewed: 12/3/08
Page last modified: 12/3/08
Content source: Division
of Reproductive Health,
National Center for Chronic Disease
Prevention and Health Promotion
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