Question

Fertility monitors are available that attempt to monitor the ovarian cycle to predict times of highest fertility. Knowing sperm can survive for up to 5 days in the oviduct, which hormone (choose from LH, FSH, Estradiol, and progesterone) should you monitor to find peak periods of fertility? Explain your answer.

Answer 1

LH should be monitired.

The system will delineate three levels of fertility according to changes detected in the concentrations of LH and E3G. Low fertility is displayed when the probability of conception is low and these hormones are at a baseline concentration. Low fertility will be displayed from day 1 of a woman's cycle until rises above the baseline concentrations are detected. The change from Low fertility to High fertility is triggered by detection of elevated E3G concentrations, typically at concentrations between 20–30 ng/ml. The display of High fertility indicates that the woman is approaching a period of maximum fertility. High fertility is also displayed for one day after Peak fertility. The change from High fertility to Peak fertility is triggered by the detection of an LH surge, typically with a concentration >30 IU/l. The display of Peak fertility indicates that ovulation is imminent. Peak fertility is displayed on the day of the LH surge (CPFM peak day) and on the following day. Subsequently High fertility will be displayed for 1 day prior to a return to Low fertility. The changes in fertility are displayed on the monitor's LCD.

The transition from Low to High to Peak fertility is indicated by an increasing number of solid bars on the display; one bar (Level I) for Low fertility, two bars (Level II) for High fertility and three bars (Level III) for Peak fertility. In addition an egg symbol is displayed on Peak fertility days. The %T units are not displayed by the monitor; the monitor uses a built in rule-set to convert the detected changes in LH and E3G %T into the fertility status.

To use the system, on the morning after the start of menses the woman presses a button on the monitor to indicate that this is day 1 of her cycle. She then simply looks at her monitor every morning to check whether she needs to do a test. To perform a test she holds a test stick in her urine stream for 3 s. She then inserts the test stick into the monitor which reads the test stick after 5 min. On completion of the t