For five to six days following fertilization, the developing embryos are cultured in the laboratory until the blastocyst stage of development has been reached. This represents growth of about 200 cells. We at RMA culture embryos exclusively to the blastocyst stage, because published data demonstrates that extended embryo culture results in improved implantation rates and pregnancy outcomes. This means we will never do an embryo biopsy – or an embryo transfer – at three days, or anything less than the blastocyst stage.
When I think back to that time, I recall an almost constant sense of grief. Every 28th day represented another failure, another loss. All around me my friends were having their second and then third babies. My son looked at his classmates with their siblings wistfully, he wished with every birthday candle for a brother or sister and one day he asked, "Can you play tig on your own?"

In contrast, a study in 2016 compared outcomes of IVF and ICSI in patients with unexplained infertility and normal semen quality and showed promising results using ICSI 3. It was found that ICSI oocytes (84.5%) had a significantly higher fertilization rate compared to those inseminated by conventional IVF (67.6%). Moreover, there were no cases of complete fertilization failure (CFF) in the ICSI group, but CFF occurred in 7.9% of the IVF group.
The information on this website is of a general nature and available for educational purposes only and should not be construed as a substitute for advice from a medical professional or health care provider. Should you have any concerns about your health, or of that of your baby or child, please consult with your doctor. You also acknowledge that owing to the limited nature of communication possible on interactive elements on the site, any assistance, or response you receive is provided by the author alone. Parenting.Firstcry.com accepts no liability for any errors, omissions or misrepresentations. Your use of this site indicates your agreement to be bound by the Terms of Use.

During the selection and transfer phases, many embryos may be discarded in favour of others. This selection may be based on criteria such as genetic disorders or the sex.[125] One of the earliest cases of special gene selection through IVF was the case of the Collins family in the 1990s, who selected the sex of their child.[126] The ethic issues remain unresolved as no consensus exists in science, religion, and philosophy on when a human embryo should be recognised as a person. For those who believe that this is at the moment of conception, IVF becomes a moral question when multiple eggs are fertilised, begin development, and only a few are chosen for implantation.[citation needed]


Within the Orthodox Jewish community the concept is debated as there is little precedent in traditional Jewish legal textual sources. Regarding laws of sexuality, religious challenges include masturbation (which may be regarded as "seed wasting"[129]), laws related to sexual activity and menstruation (niddah) and the specific laws regarding intercourse. An additional major issue is that of establishing paternity and lineage. For a baby conceived naturally, the father's identity is determined by a legal presumption (chazakah) of legitimacy: rov bi'ot achar ha'baal – a woman's sexual relations are assumed to be with her husband. Regarding an IVF child, this assumption does not exist and as such Rabbi Eliezer Waldenberg (among others) requires an outside supervisor to positively identify the father.[133] Reform Judaism has generally approved IVF.[129]
As a result, most patients need to undergo multiple cycles, and as we pointed out in a another lesson, no cycle is as likely to succeed as the first one. Below is data out of the UK published in the Journal of The American Medical Association that illustrates that after a few cycles most younger patients succeed with IVF but that is not necessarily true for older patients.
Assisted hatching. About five to six days after fertilization, an embryo "hatches" from its surrounding membrane (zona pellucida), allowing it to implant into the lining of the uterus. If you're an older woman, or if you have had multiple failed IVF attempts, your doctor might recommend assisted hatching — a technique in which a hole is made in the zona pellucida just before transfer to help the embryo hatch and implant. Assisted hatching is also useful for eggs or embryos that have been previously frozen as the process can harden the zona pellucida.
SART, in conjunction with, The American Society for Reproductive Medicine (ASRM), has published guidelines for the recommended number of embryos to transfer (add to link). These guidelines are based on SART-sponsored research which continually evaluates success rates around the country.  This helps to determine the optimal number of embryos to transfer, based on specific patient characteristics, like age and history of prior IVF.  Patients may require several cycles of treatment to have a baby. Success rates remain fairly constant over several cycles, but may vary greatly between individuals.  
For five to six days following fertilization, the developing embryos are cultured in the laboratory until the blastocyst stage of development has been reached. This represents growth of about 200 cells. We at RMA culture embryos exclusively to the blastocyst stage, because published data demonstrates that extended embryo culture results in improved implantation rates and pregnancy outcomes. This means we will never do an embryo biopsy – or an embryo transfer – at three days, or anything less than the blastocyst stage.
Assisted hatching. About five to six days after fertilization, an embryo "hatches" from its surrounding membrane (zona pellucida), allowing it to implant into the lining of the uterus. If you're an older woman, or if you have had multiple failed IVF attempts, your doctor might recommend assisted hatching — a technique in which a hole is made in the zona pellucida just before transfer to help the embryo hatch and implant. Assisted hatching is also useful for eggs or embryos that have been previously frozen as the process can harden the zona pellucida.

Sometimes problems getting pregnant for a second or subsequent time are related to a complication that occurred in a prior pregnancy or prior to delivery (damage to the uterus, for instance). But most often, secondary infertility is caused by the same factors that would cause primary infertility — issues like advanced age, obesity, ovulation problems and so on.
×