ATLAS OF IVF EMBRYOS - Day 0 and 1

Atlas Of IVF Embryos. Dr Sai, Senior Embryologist, Malpani Infertility Clinic

Unfortunately, most patients doing IVF treatment are quite clueless about the most important end-result of the IVF cycle - the embryos ! This atlas will help you understand what your eggs and embryos should look like, so you have a better understanding of what happens in the IVF lab !

DAY 0

MATURE OOCYTE CUMULUS COMPLEXES

THESE ARE MATURE OOCYTE CUMULUS COMPLEXES, IDENTIFIED IN THE FOLLICULAR FLUID ASPIRATED DURING EGG COLLECTION.

POST MATURE OCCYTE CUMULUS COMPLEX

STRIPPED EGGS
MATURE EGGS :

THIS IS A MATURE EGG (SURROUNDING CUMULUS CELLS HAVE BEEN STRIPPED OFF)

POLAR BODY AT 12 O CLOCK POSITION INDICATES THAT THIS IS A MATURE EGG AT METAPHASE II
STRIPPING IS MANDATORY FOR PERFORMING ICSI ON THEM.
CUMULUS NEED NOT BE STRIPPED FOR CONVENTIONAL IVF.

THIS EGG IS NOT A MATURE EGG. BUT A TINY POLAR BODY WHICH IS PROTRUDING OUT AT 12 O CLOCK POSITION, INDICATES THAT IT WILL SOON BECOME MATURE.

IMMATURE EGGS

Metaphase I egg

We can perform ICSI on Metaphase I eggs. The fertilization rate for Metaphase I eggs is 50 %.

Egg with Germinal Vescicle

THIS EGG HAS A CLEAR GERMINAL VESCICLE IN IT, WHICH INDICATES IT IS AN IMMATURE EGG. WE CANNOT DO ICSI ON THIS EGG. WE CAN USE IVM ( IN VITRO MATURATION) FOR THESE EGGS. AFTER 24 HOURS, SOME OF THEM MAY MATURE AND BECOME M2 ( METAPHASE II) AT WHICH TIME WE CAN DO ICSI FOR THEM

ABNORMAL EGGS

EGG WITH ABNORMAL ZONA EGG WITH ABNORMAL CYTOPLASM.

EGG WITH 2 POLAR BODIES.

POOR QUALITY EGGS

EGGS WITH DARK CENTRAL GRANULATION IN CYTOPLASM.

EGG WITH VACOULATION IN CYTOPLASM

UNFORTUNATELY, THERE IS NO WAY WE CAN PREDICT THE QUALITY OF EGGS BEFORE WE STRIP THEM.
THIS IS WHY STRIPPING THE EGGS FOR ICSI PROVIDES US WITH VALUABLE INFORMATION ABOUT EGG QUALITY !

DAY 1

DAY 1 EMBRYOS ( ALSO CALLED ZYGOTES) ARE SCORED CONSIDERING

• THE PRESCENCE OF CYTOPLASMIC HALO
• NUCLEAR SIZE AND ALIGNMENT, NUCLEOLI NUMBER AND DISTRIBUTION.

PICTURE A - HALO POSITIVE ZYGOTE PICTURE B - HALO NEGATIVE ZYGOTE

ZYGOTES ARE SCORED ACCORDING TO THE Z-SCORING SYSTEM.

1. • PRESCENCE OF CYTOPLASMIC HALO
   • NUCLEOLI NUMBER AND DISTRIBUTION
   • PICTURE A IS Z1 ZYGOTE WITH EQUAL NUMBER OF NUCLEOLI, ALIGNED AT THE PRONUCLEAR JUNCTION.
   • PICTURE B IS A Z2 ZYGOTE WITH EQUAL NUMBER OF NUCLEOLI, SCATTERED IN THE TWO NUCLEI.
   • PICTURE C IS A Z3 ZYGOTE WITH UNEQUAL NUMBER (DIFFERENCE OF MORE THAN 2 NUCLEUS) AND / OR SIZES OF NUCLEOLI.
   • PICTURE D IS A Z4 ZYGOTE WITH SEPERATED PRONUCLEI AND UNEQUAL NUMBER OF NUCLEOLI SCATTERED IN THE TWO NUCLEI.

NORMAL ZYGOTE

Z1 EMBRYO

POOR QUALITY ZYGOTE

Z3 EMBRYO

ABNORMAL ZYGOTES

ZYGOTE WITH 3 PRONUCLEI

ZYGOTE WITH 2 PRONUCLEI WITHOUT NUCLEOLI

ZYGOTE WITH 1 PRONUCLEUS

To see what your embryos will look like on Day 2 and Day 3, check out  https://www.drmalpani.com/articles/atlas-of-ivf-embryos-day-02-and-03