Researchers have created the most detailed 3D map of an embryo yet.
The 3D map shows the early structures of major organs in the mouse embryo at 11.5 days past conception (equivalent to 38 days past conception in humans).
To build this map, researchers generated about 90 slices of an embryo and analyzed the gene expression data (RNA transcriptome) for each of the ~8 million cells in these slices.
Each dot shown in the video corresponds to a single cell.
Using this data, the researchers built a model called Spateo, which can one day be used to create 3D embryo maps for any species, including humans.
The researchers believe that these maps could help identify causes of congenital diseases.
Check out more details on Nature, link is in the comments. Want to stay up to date on new IVF research and news? Follow me and send me a DM with your email and I'll sign you up to my weekly newsletter!
Image and video source: Qiu et al. 2024. Spatiotemporal modeling of molecular holograms. Cell. CC-BY-4.0.
Researchers have used high-resolution microscopy to observe ovulation in mice, revealing it occurs in three distinct phases.
Each month, a single follicle from one of the ovaries makes it to ovulation, releasing an egg into the fallopian tube where it can be fertilized by sperm to create an embryo that can implant in the uterus.
Researchers, in a recent Nature Cell Biology study, isolated mouse ovarian follicles to capture the ovulation process in high resolution.
They noted three distinct phases of ovulation:
1) Follicle expansion, where fluid flows into the follicle, causing it to grow.
2) Contraction, where smooth muscle cells in the outer follicle layer contract to squeeze the follicle.
3) Follicle rupture, where contractions push follicular fluid containing the egg out from the follicle, completing ovulation. In the video, you can see the egg emerge.
Check out more details from the Max Planck Institute, link is in the comments. Want to stay up to date on new IVF research and news? Follow Embryoman and send me a DM with your email and I'll sign you up to my weekly newsletter!
Source: Thomas, C., Marx, T.L., Penir, S.M. et al. Ex vivo imaging reveals the spatiotemporal control of ovulation. Nat Cell Biol (2024).
A study published in the journal Cell reveals the proteins responsible for fertilization.
Fertilization begins with the sperm binding to the egg cell, followed by the fusion and combining of their genetic material.
It has been unclear how sperm specifically binds to the egg, but recent research provides insights.
Researchers discovered that three sperm proteinsโTmem81, Izumo1, and Spaca6โwork together to bind to the JUNO protein on the egg cell's surface.
This group of proteins on the sperm acts like a key, fitting into the lock of the egg cell to initiate binding.
The AI technology AlphaFold was used to predict interactions among these proteins, which led to the identification of Tmem81's role.
Animal experiments with zebrafish and mice showed that animals lacking Tmem81 were infertile, despite having normal sperm, confirming the protein's crucial role in fertility.
In the accompanying video, you can see a number of sperm (in orange) binding to the eggโs zona, or shell. This binding occurs through the interaction between the sperm proteins and the JUNO protein on the egg. Once a sperm penetrates the egg, there is a massive release of calcium ions (in blue), which oscillate to activate the egg's mitochondria. This activation boosts energy production, allowing the egg to resume meiosis and complete the fertilization process.
Video used with permission, thanks to Victoria Deneke, Pauli lab, IMP Vienna.
You can read about the full study in The New York Times, link in the comments. Want to stay up to date on new IVF research and news? Send me a DM with your email and I'll sign you up to my weekly newsletter.
Let's walk through this time-lapse of an embryo graded as a 4AB! Check the link in the comments for more info on embryo development and grading, and send me a message if you need help understanding your embryo.
๐๐ก๐๐ญ ๐ค๐ข๐ง๐ ๐จ๐ ๐๐ฆ๐๐ซ๐ฒ๐จ ๐ ๐ซ๐๐๐๐ฌ ๐๐ข๐ ๐ฒ๐จ๐ฎ ๐ซ๐๐๐๐ข๐ฏ๐?
Normally embryos become blastocysts on day 5, but sometimes embryos take longer to develop and may become a blastocyst on day 6, day 7 or even day 8.
Embryos can also develop faster and become blastocysts on day 4!
Generally, the faster an embryo develops into a blastocyst, the better its chances of leading to a live birth.
Many IVF clinics will culture embryos to day 6, but some will extend the culture further to day 7. I think it's important to work with clinics that culture to day 7.
Some studies have found that day 7s have a good chance, without any harm to the baby's health, and it helps patients make blastocysts who otherwise wouldn't.
One study found that about 10% of patients got their blastocysts on day 7. In other words, if these patients didn't culture to day 7, they wouldn't have any blastocysts to transfer!
Sometimes it's possible to go even beyond day 7 -- to day 8. In 2021, the first reported case of a day 8 healthy live birth was reported. It was PGT-A tested and good quality.
Typically, labs won't culture embryos to day 8, but "good quality [PGT-A tested] embryos after 8 days of culture should be considered for embryo transfer," the researchers reported in Fertility & Sterility.
Learn more about embryo grading and success rates on Remembryo, link is in the comments. Want to stay up to date on new IVF research? Send me a DM with your email and I'll sign you up to my weekly newsletter.
๐๐จ ๐ฒ๐จ๐ฎ ๐ก๐๐ฏ๐ ๐๐ง๐ฒ ๐๐๐ฒ ๐, ๐ ๐จ๐ซ ๐ ๐๐ฅ๐๐ฌ๐ญ๐จ๐๐ฒ๐ฌ๐ญ๐ฌ? ๐๐๐ฏ๐ ๐ฒ๐จ๐ฎ ๐ญ๐ซ๐๐ง๐ฌ๐๐๐ซ๐ซ๐๐ ๐๐ง๐ฒ? ๐๐จ๐ฐ ๐๐ข๐ ๐ข๐ญ ๐ ๐จ?
โฌ๏ธโฌ๏ธ New research! โฌ๏ธโฌ๏ธ
In a new study, researchers have captured changes in the maternal brain during pregnancy by MRI scans.
Scientists took 26 brain scans of a woman who had conceived by IVF every few weeks, starting from 3 weeks before IVF to 2 years after birth.
The study revealed widespread reorganization of the brain, including a steady decrease in gray matter in areas involved in social cognition.
This likely reflects neural circuit fine-tuning, comparable to how Michelangeloโs David was chipped away from a block of marble, the researchers said.
One expert described this work as "truly heroic," and may improve our understanding of postpartum depression and the connection between preeclampsia and dementia.
The research was part of the Maternal Brain Project, an effort that aims to gather more data from pregnant women to understand health risks, and was published in Nature Neuroscience.
Check out the full story on The Guardian, link is in the comments. Want to stay up to date on new IVF research and news? Send me a DM with your email and I'll sign you up to my weekly newsletter.
For the first time, researchers have successfully performed an ultrasound-guided egg retrieval in a domestic cat. Note that this is to help extend fertility in cats and for conserving wild cat species. Check the link in the comments for more info.
What's a low- or high-level mosaic embryo? For more information, check out the link in the comments.
How many eggs and embryos should you expect to get, based on your age? In this video, I go over a 2022 study that reports on the median number of eggs retrieved in good prognosis patients, along with the number of mature eggs, fertilized eggs and usable blastocysts, based on age. For more information, check the link in the comments.
This video goes over the 3 types of eggs you can get after a retrieval -- GV, M1 and M2 eggs, and how you might be able to get more mature eggs!
To learn more, head to the link in the comments.
Here I discuss the trophectoderm, the part of the blastocyst that becomes the placenta, and a new study that took some pictures that really help to visualize what it is.
For more info on blastocyst development/grading, check the link in the comments.
Researchers found that excessive bending of a Cryotop, a cryostorage device used to freeze eggs or embryos, can damage embryos and reduce thaw survival rates.
A cryostorage device is a device thatโs used to freeze embryos or eggs. The sample can be frozen within a straw thatโs sealed, or it can be frozen on a stick-like Cryotop or Cryolock device.
Both Cryotop and Cryolock devices have a flexible end where the embryos are deposited for freezing, and this end can be bent.
In a new study, researchers wanted to know if bending this end, which may be accidently done by the embryologist, could damage frozen embryos.
They loaded up Cryotops with embryos, froze them, and then purposely bent the device.
After thawing them, the embryos had visible damage and a lower survival.
The authors recommend that embryologists should be properly trained to avoid bending of the Cryotop device, as this could damage the embryos.
Check out all the details on Remembryo, link is in the comments. Want to stay up to date on new IVF research? Send me a DM with your email and I'll sign you up to my weekly newsletter.
