Let us review the two basic fertility sensing techniques (LH concentration measurement and BBT measurement) before going to the overall system design.
(i) Urine based LH concentration measurement:
Here a test strip is used which has three marked levels:
1. Stop line
2. Test band
3. Reference band
Initially, only the stop line marking is present in the strip.
A small amount of the women’s urine is taken in a cup. The test strip is dipped into the cup in such a way that the urine level does not exceed the stop line marking (refer to Figure 3).
Figure 3: LH testing procedure
This strip is removed after few seconds and kept flat for a few minutes, after which appear the test band and the reference band. The reference band used for comparison, and if the test band is darker than the reference band, this indicates a higher LH hormone concentration. In other words, it indicates that the woman is about to reach her ovulation period. If it is lighter, this means she has not reached the ovulation period yet. (ii) BBT measurement:
Here a good quality temperature sensor is used to measure the woman’s body temperature every morning. As shown in Figure 2, the BBT remains low before the ovulation day. A sudden hike of about 0.2-0.3°C in the basal body temperature measurement indicates that the ovulation day should occur in a day.
An interesting view of the presented work, and something actually does work, such methods are used as an alternative to the pill (not LH measurement, temperature). It also has the benefit of reducing the likelihood of birth defects which given the impact on families and the community is another noble cause. Yes we should be reducing the world population (preferably to around 2billion) but if we don't reinvent our economy I'm afraid the outcome may be almost as undesirable.
@EREBUS: Yes, this system can also be used by women who do not want to get pregnant. This can avoid the usage of contraceptive pills which may have some side effects.
@EEWIZ: Thanks for providing this statistical information. This is absolutely correct. I think designing such gadgets would be of great use in those Asian countries.
@ EREBUS this is not the case in everywhere.. if you look at places like hongkong/japan/korea/singapore the TFR(total fertility rate) is much lower than the replenishment rate of 2.1. ie..these countries can potentially get wiped off in future. Ofcourse the main reason is social and cultural and not medical. but then, there is a small percentage who will have medical/stress related problems to whom things like this could be helpful.
With our current population growth I fail to see how helping more women get pregnant is a benefit. Now if you use it to help women AVOID getting pregnant, we can help lift a lot of people out of poverty.
Just my opinion.