The purpose of cycle monitoring is to determine whether you have an ovarian follicle, ovulation and corpus luteum formation. Normally, an egg cell grows in the follicle every month. After ovulation, the egg cell enters the fallopian tube and is fertilised by a sperm. Only four days later does the fertilised egg arrive in the uterus and implant in the uterine lining. During the first weeks of pregnancy, the corpus luteum, which is formed on the ovary from the ruptured follicle, produces the hormone progesterone to support pregnancy. Women with regular, approximately 28-day cycles, are generally expected to have unremarkable cycles when monitored. Women who have a prolonged cycle, irregular bleeding or the first signs of menopause, should have their follicle growth checked if they wish to have children.
For this purpose, an ultrasound examination (vaginal) is performed on the 10th cycle day. The follicles on the right and left ovaries and the thickness oft he endometrium are measured. Usually, only one larger follicle is seen. If this is not yet large enough, it is checked again after two days. A ripe follicle measures about 20mm. Often a number of smaller follicles (around 10mm) can be seen at the same time. If a larger follicle is present, a blood sample is taken to determine E2 (estradiol) and LH (Luteinizing hormone). The estradiol correlates with the maturity of the egg and the LH surge causes ovulation. An optimal case would be the detection of an 18-22mm follicle at mid-cycle with adequate estradiol and LH levels. There are variations from cycle to cycle, however if you have no follicle growth over multiple cycles, we will recommend hormone stimulation.
