This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
In a young female of reproductive age with regular menstrual cycles of 28 days, ovulation occurs around 14th day of periods. When is the first polar body extruded ? 
Select and explain. 
A. 24 hrs prior to ovulation, B. Accompanied by ovulation, C. 48 hrs after the ovulation, D. At the time of fertilization
B: Accompanied by ovulation
Answer: B: Accompanied by ovulation 
Explanation: Most of the standard text books say the first polar body is expelled just before or shortly before ovulation.
Which does not mean that it is released 24 hours before ovulation.
While still in the ovary the ovum is in the primary oocyte stage. Shortly before it is released from ovaria follicle (i.e. shortly before ovulation), its nucleus divides by meiosis and a first polar body is expelled from the nucleus of the oocyte. The primary oocyte then becomes the secondary oocyte. In this process each of the 23 unpaired of chromosomes loses one of its partners which become the first polar body that is expelled. This leaves 23 unpaired chromosomes in the secondary oocyte. It is at this time that the ovum, still in the secondary oocyte stage is ovulated into the abdominal cavity
So, first polar body is released at the time of ovulation i.e. Option “b”