Stork Diary.
to Share Stork Life Events

Is ooplasm matured? Polscope, a great helper of IVF

Is ooplasm matured? Polscope, a great helper of IVF

 Spindle of every oocytes is like heart of human. Although we can't see it, it plays the most important role. Stork fertility center list out some groups that are suitable to use polscope to observe spindle.



Under microscope, our embryologists pick out a sperm with great activity and morphology then inject it into an oocyte. During this process, the polar body will be placed at 12 o'clock direction to avoid the invisible heart of oocyte-- spindle. It is formed by microtubules, centrosomes and chromosomes. In the procedure of cell division, spindle leads chromosomes to separate from the middle of cells to bipolar. According to scientific studies, spindles are not right under polar bodies. There are about 30% of oocytes will have the situation of spindle deviation. Therefore, it might be damaged in regular operating mode. Which leads to chromosome abnormal and affect development of embryos. It's like heart of human. We can't see it from outside but it plays the most important role.

Here are the statistic results from other center. It is shared in 2019 annual meeting of Taiwanese Society of Reproductive Medicine.

  • From 2018.09 to 2019.05
  • 31 IVF clients. (31cycles)
  • 114 mature MII oocytes
  • observe the oocyte spindle 4-6 hours after oocyte retrieval
  • With the first polar body as the center, define its left and right 45 degrees as zone A, and the rest as zone B.

The research team finds out the following points.

  1. We can successfully observe 75% oocyte spindle 4-6 hours after oocyte retrieval. And there's no difference for clients above or under 40 years old.

  2. Most of oocyte spindle (81.4%) are under first polar body. But there is still 18.6% possibility that spindle of oocyte will shift and not fall below first polar body.

  3. Compared with those under 40, the probability of spindle falling into zone B is higher (27.8% v.s. 16.9%) among those ≥40 years old. (See the figure and the table below).



 

<40 years old

≥40 years old

cycles

20

11

Matured oocyte number(MII)

86

24

Spindle visible

75.6% (65/84)

75% (18/24)

Spindle invisible

24.4% (21/86)

25% (6/24)

spindle falling into zone A

83.1% (54/65)

72.2% (13/18)

spindle falling into zone B

16.9% (11/65)

27.8% (5/18)

Compare the culture results of those oocytes that use polscope to observe spindle before ICSI and without observation, it shows that there are no difference. However, the group that's over 40 years old have the better fertilization rate. And the division rate can reach to 100% for Day 3.

 

With confirmation of

the spindle position

Without confirmation of

the spindle position

(Assuming it is directly

 below the first polar body)

P-value

Fertilization rate  (normal fertilization number/matured oocyte number)

Total (regardless of age)

72.8% (78/107)

71.4% (85/119)

NS

<40 years old

72.6% (61/84)

71.4% (75/105)

NS

≥40 years old

73.9% (17/23)

71.4% (10/14)

NS

Division rate (division embryo numbers/ normal fertilization numbers)

Total (regardless of age)

6.2% (75/78)

94.1% (80/85)

NS

<40 years old

95.1% (58/61)

94.7% (71/75)

NS

≥40 years old

100% (17/17)

90% (9/10)

NS

Stork Fertility Center introduced spindle polscopes in 2017 to confirm the maturity stage of the oocytes. Because oocyte that just spit out first polar body needs another 2~3 hours to reach the best fertilization time,  Metaphase II. The observation of the spindle can avoid the oocytes which look mature from appearance (the polar body has been spit out), but the ooplasm is still in the late phase of the first meiosis (telophase) or those immature oocytes which are in prophase of second meiosis. So embryologists can control more accurately about the time to do insemination and avoid to freeze oocytes in telophase (the spindle is still framed between the ooplasm and the first polar body). Because the dehydration and shrinkage in the freezing process may cause fracture and damage of the spindle.


It is also used to locate the position of the spindle during fertilization.  For the clients with reduced ovarian function or elderly clients with low number of eggs or low quality sperm. Embryologists will usually choose to do Intracytoplasmic Sperm Injection( ICSI) for insemination. Therefore, using polscope to observe the spindle position in oocytes can avoid accidently injure it during fertilization. In addition, according to the scientist research and the statistics of the above-mentioned team, elderly patients do have a higher spindle deviation phenomenon. So it is more recommended to use a polscope to identify the position of the spindle to grasp every precious oocytes in each cycle. We also found that thawed oocytes are more likely to have higher spindle deviation rate. Because the oocytes have undergone freezing and thawing (shrinkage, retraction) process. With polscope observation, it allows embryologists to get the hang of the best time and the proper position during inserting the needles to do fertilization. Hope that it can maximize the value of each oocyte of our clients.


Register：Oversea Form

Facebook：e-Stork FB Page

E-mail：en_service@icryobank.com

WhatsApp：+886-905-737-501  


Stork Fertility Center Stork Fertility Center Author

POSTS

Stork Fertility Center
Copyright ©
| Distributed By Gooyaabi Templates