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Infertility/Fertility/Blastocyst vs 3 day embryo


I wanted to ask if using blastocysts is ideal.
Is this the norm?
Are day 3 embryos that don't turn into blastocysts genetically abnormal or just not strong?
I produced 16 eggs ( I had 15 follicles) I wanted to ask, how do women produce more eggs than their follicle count? Reading on boards it seems this can happen and I'm wondering if I was under stimulated. I had 7.5 mg letrozole for 2 days. Then I had 225 gonal and later added in one menopure and then eventually ovadrill.
I asked to do SET cause I do want twins, I am 5 feet and 100 pounds and am very concerned about carrying two.  I was told only 8 eggs were mature. Is that typical. Is that from under stimulation? I was told this is common. There are labs that let eggs mature in the lab, do you consider that an option in the future? I was told my fsh Amh and afc are all right for my age and good for ivf. But I was told we only got 6 embryos, 4 blastocysts and I sprung for pgs only to find out one embryo was euploid. It was so much money. I guess it's better I know the others weren't good but then I feel unhappy about doing the blastocyst thing. Having only one good one out of FOUR seems horrible for my age, 36 and a half. They told me the blasts looked perfect, goes to show you.  It seems so many women get pregnant from 3 day embryos, not clear what's better. Might I ask what's the average number of cycles people go through? I was told I have about a 50% chance of pregnancy. If it doesn't work I will be mortified that I paid so much for pgs and chose blastocyst.  I was counting on having some to freeze. Also wanted to ask how do blastocysts thaw? Worse or better than day 3 embryos because other people seem to just freeze all the extra day 3 embryos? Is that better? What's the average number of ivf cycles? Do you think ivf itself may compromise egg development? I guess I could've had zero good blastocyst but one of four is so so disappointing. I think maybe I needed more eggs to start. No one explained to me what to expect until AFTER all this and then they reassured me all my numbers were normal including having just one blast,  PGS is flat cost up to 6 blasts so I feel like maybe I could've done two cycles and saved on PGS though I don't know if they can thaw and refreeze blasts. I had to pay for Icsi also because they said if I didn't the pgs would be a lot more because the sample can contain extra sperm and you have to take blood from both parents. I wanted to not do Icsi because natural seems better. Any thoughts here? Thanks so much. Also following up on another post from someone else, you said you rarely had genetically abnormal babies born from blasts, were these things that could've been detected in amniocentesis. I was advised that doing pgs doesn't mean you shouldn't do cvs or amnio

Hello Jen from the U.S. (New York),

In general I don't answer when there are more than 5 questions, but since some of your questions are short, I'll go ahead in this case.  Let me take them question by question.
1.  Previously I have been a disbeliever that blastocysts were better than D#3 embryos, but this year I have been doing lots of blastocyst transfers and my pregnancy rates seem better.  Blastocysts are only better because they are closer to the implantation stage, and if you are only choose a few (such as SET), this helps to identify which ones to choose.  Embryos that don't progress to blastocyst are, in general, less "strong", but not necessarily genetically abnormal.  Even genetically abnormal embryos can progress to blastocyst.
2.  There are only two ways that I can think of, (1) the number of follicles was undercounted because it is hard to count sometimes an ovaries are three dimensional structures or (2) you had more than 1 egg in a follicle which does occur in nature.
3.  There is no "typical" in IVF as clinic, doctors, protocols and responses vary widely.
4.  Your protocol was definitely a low stim protocol.  You could have been stimulated harder by using a higher dosage of medication but it sounds like your doctor used a "mini-IVF" protocol in order to limit the number of eggs retrieved.
5.  In Vitro Maturation is not a common procedure at this time, and is considered experimental only.  If you wanted that, you would have to go to a specific clinic that offered it.
6.  I can't tell you what the average is Nation or worldwide.  In my practice, only 66% get pregnant on their first try.  Then it goes up to 86% by two tries and 92% by three tries.  This varies from clinic to clinic.
7.  No.  I don't think IVF compromises egg quality.
8.  ICSI is definitely the way to go.  99% of my patients use ICSI.  The down side is that the eggs don't fertilize and then you have nothing.
9.  I am not a strong advocate of PGS in under 36 years old patients because if the embryo is abnormal, you will either not get pregnant (no implantation) or you'll have a miscarriage (natures quality control).  In addition, now a days you can do genetic testing very early in the pregnancy.  In MY EXPERIENCE, the chances of a genetically born child is lower in IVF because the weaker eggs don't make it through the entire process.  In MY EXPERIENCE, I've only had two cases of Down's syndrome pregnancies in 20 years and both were over 40+ years old patients.  Of course, that does not consider the miscarriages that have occurred, which we could not test.

Overall, I think you did everything correctly as you were recommended, but maybe you were shortchanged a little.  If you were my patient and wanted to do PGS, I would NOT have used a low stim or mini-IVF protocol, because I want to have as many blastocysts as possible to test.  This is because I know that there is a high chance that the majority will not be genetically normal.  I think that if you are going to do IVF again, you should do a full stimulation protocol IVF with the goal to retrieve as many eggs as possible (up to 20 so you don't develop OHSS), get as many fertilized as possible, as many embryos to blastocyst as possible then do the PGS to have multiple normal embryos to choose from.  This way, even if you only transfer one at a time, at least you will have embryos frozen to try again and again until you get pregnant, or if you get pregnant, for your next pregnancy without to full expense of a full IVF/ICSI/PGS cycle.  


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Edward Joseph Ramirez, MD, FACOG


I am a specialist in infertility and advanced gynecological care. I can answer questions about infertility, gynecology related ills, menopause...virtually anything that affects women's health. PLEASE tell me where you are writing from as I am always interested.


I have been practicing as an Ob/Gyn and Infertility Specialist for over 23 years. Gynecology, advanced laparoscopic surgery, basic infertility, IUI's, IVF, reproductive surgery, and ovulation induction are all areas of my expertise. I am Board Certified. I have been doing In Vitro Fertilization in my clinic for 19 years.

American College of OB/GYN, American Board of Obstetrics and Gynecology, American Society of Reproductive Medicine, California Medical Association, American Association of Gynecologic Laparoscopists, Fellow of The American College of Obstetricians & Gynecologists

American Journal of Obstetrics and Gynecology, Wall Street Journal, Monterey Herald, SERMO, Women's Health and Fertility Blog

Medical Degree from Stanford University, Residency at Tripler Army Medical Center, Reproductive Training at Pacific Fertility Center, San Francisco

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