A womens ovary has 6 million oocytes at puberty. At every menstrual cycle a group of antral follicles, 10-15 in number start growing. An antral follicle consists of an oocyte (female egg) surrounded by granulosa and theca cells (two types of cells)- which nourishes the oocyte and secrete female hormone called estrogen. As estrogen collects around the oocyte the antral follicles look like small fluid filled cysts.
They grow at a rate of 2 mm per day, by the 5th or 6th day of menstrual cycle, majority of these antral follicles undergo artesia and only one grows. This growing follicle can be seen by Transvaginal ultrasound daily- This is called follicular study. The study starts around 8th to 10th day of menstrual cycle and continues till the follicle ruptures. It usually ruptures after it achieves 20 mm size.
In regularly menstruating women, follicle ruptures 14 days before expected menses; that is follicle will rupture on 16th day in a women who has 30 days cycle. With rupture of the follicle, oocyte with few granulosa cells falls out of the ovary and is picked up by the fallopian tube.
What is follicular study?
Follicular study is the procedure in ehich the follicle size is checked on ultrasound from the 2nd day to 14th or 15th day of periods. this is done to track thr growth of the follicle in the ovaries. Only a follicle above the size of 20mm will release a mature egg which will help us achieve pregnancy.
How many times do i have to visit the clinic during folicular study?
There will be 4 to 5 visits to the clinic in a span of 15 days. If you have done follicular study beforew the doctors will know the growth pattern of the follicle hence number of visits can be reduced.
How is follicular study done?
The best way to perform folicular study is through a transvaginal sonography, during this the ultrasound picks up the images of the follicle and gives us the most accurate size of the growing follicles. Thew image below shows how the scan is seen
As seen in the picture on the left circular black structures are the follicles in the ovaries. They grow by 2mm everyday and this is verified on follicular study.
Is follicular study painful?
You might feel little discomfort but it is not at all painful.
Who needs follicular study?
Patients who have recently planned to have a pregnancy and want to know their ovulation days(Fertile period), follicular study is the best option.