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Ultrasound scan
 
 
 
 
 
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Ultrasound Scan
 
 
 
Breast scan

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Female Physiology

Every woman will have menstrual cycle which recurs regularly from puberty until menopause except when pregnancy takes place. Although each woman has an indivudual cycle which varies in length, the average cycle is taken to be 28 days long. The first day of the menstrual cycle is the first day of menses.

The menstrual cycle consists of 3 main phases, the menstrual phase, proliferate phase and secretory phase. The cycle is regulated by 4 hormones, follicle stimulating hormone (FSH), luteinizing hormone (LH), oestrogen and progesterone. FSH and LH are produced by the anterior pituitary gland, while oestrogen and progesterone are produced by follicle and corpus luteum respectively.

The menstrual phase is characterised by vaginal bleeding, which lasts for 3 to 5 days, at the begining of a menstrual cycle. During this period, a few primordial follicles (sac that contains egg) are recruited to grow. This recruitment is regulated by FSH.

The proliferative phase follows menstruation and lasts until ovulation (egg released from the ovary). During this period, a few eggs are stimulated to grow by the FSH and oestrogen. However, usually only one dominant egg will reach full maturation. When the LH levels exceed certain threshold, ovulation occurs. It usually takes place on the day 14 of a 28-day-long menstrual cycle. On the other hand, the endometrium (lining of the uterus) regrow and thicken so that it is well-prepared to accept the resulting embryo if fertilisation occurs. The growth and development of both egg and endometrium are stimulated by oestrogen which is produced by the follicle.

If there is no fertilisation occurs after ovulation, the empty follicle (the egg was released into fallopian tube at ovuation) will switch to corpus luteum. Now, the proliferative phase is switched to secretory phase which lasts for 14 days until the next menstrual cycle. The corpus luteum no longer produces oestrogen, but it produces progesterone which makes the endometrium thicker with more glands and spongy in appearance.

The drop of oestrogen levels cause the degeneration of corpus luteum and decreased of progesterone. Consequently, the endometrium can no longer be maintained. It sheds and vaginal bleeding takes place again.