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Pregnancy Rates of Human Reproduction & ART
Human reproduction is a relatively unreliable process.
In the average fertile couple, the probability of fertilization
for any particular exposure of egg to sperm may be approximately
80%. But the probability of a live birth is actually 20% on
an average.
Typical Reasons
for Failure in Pregnancy
Usually, by the time of the first expected menstrual period
after ovulation, approximately one-half of the early embryos
usually fail to develop. Many of these lost embryos could
be fundamentally abnormal and therefore incapable of survival.
The menstrual period would occur on time, and an early pregnancy
could be overlooked. If a menstrual period is missed, approximately
one-fourth of the remaining embryos may still die later.
Clinical studies done among population groups who do not use
contraception show that the pregnancy rates in these people
is a staggering 20%.
Infertility
In practical terms, if 10 couples get married and try for
a child, one or two couples will conceive every month. At
the end of one year, nearly 9 out of the 10 couples will have
a baby. The couple who failed to conceive 5 to 10 %.
Infertility
is not an abnormality but a condition, caused by both male
and female reproductive factors.
At the same time, Artificial Reproductive
Techniques are the answer to treat infertility and these
have proven successful all over the world.
Success Rates
ART programs however are man-devised, scientific methods of
reproduction and these too have a success threshold. Hence
choosing an IVF clinic becomes imminent.
IVF
It is unlikely that the rate of establishing a pregnancy from
each egg by fertilization and development In Vitro followed
by embryo transfer can improve the rate of normal reproduction.
Maximum success per egg in any one cycle is likely to be in
the 20-30% range. In most experienced IVF
programs, rates of ongoing pregnancy have usually been in
this range or lower, even though more than one egg is often
fertilized and several embryos transferred back into the uterus
in most patients.
IVF Rates:
IVF pregnancy rates are one of the most misunderstood aspects
of IVF treatment. IVF pregnancy rate statistics can be manipulated
to achieve nearly any desired statistical percentage through:
Patient
selection
Treatment
selection
Cycle
cancellation procedures
Cycle
reclassification
Numbers
of embryos transferred
Transfer
Cryopreservation
criteria
Other
variables.
No amount of
managing of population data, however helps, and it may adversely
effect the care of the individual patient.
Choosing an IVF Clinic
IVF pregnancy rate statistics should never be used as the
primary criterion for determining the actual quality of an
IVF program. What should be kept in mind are factors like:
The total experience
Record
of innovation
Professional
reputation of an organization
Its history
of sensitive caring for patients
The absolute
integrity of its staff are far more useful guides to program
selection.
Successful conception and childbirth for any specific couple
cannot be guaranteed by any IVF program, even if the couple
undergoes multiple attempts. The probability of success depends
on many factors including the patient age, the cause of infertility,
and the talent and experience of the IVF team. IVF is of demonstrated
value for patients with absence of both fallopian tubes or
irreversible tubal blockage (where corrective surgery has
either failed or is inadvisable). Patients who are undergoing ART the cumulative pregnancy rate at the end of 4 attempts is in the region of 80%. The remaining 20% of patients can either opt for egg donation or adoption.
Overall the clinical
pregnancy rates in good IVF units worldwide is in the region
of 20 to 30 % . BabiesandUs Fertility Centre has success rates,
which are comparable to the best units in the world.
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