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%.
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.
ART programs however are man-devised, scientific methods of reproduction and these too have a success threshold. Hence choosing an IVF clinic becomes imminent.
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 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
- 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:
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.