A woman who has intercourse when her ovulation test turns from a weak positive to a negative test has a lower chance of becoming pregnant. The reason is that when the test turns negative, it proves that the woman’s egg has been expelled and the egg survives for 48 hours after expulsion, with the highest rate of conception within 24 hours after expulsion. If the eggs have died during this period, the time period is usually two to three days after the eggs have been expelled. Even if the woman has intercourse, pregnancy will not occur because the sperm does not unite with the egg. If the egg has not lost its activity during this period and is able to unite with the sperm, the woman can become pregnant. Therefore, under normal circumstances, it is best for women to have intercourse during this period when they have a strong positive ovulation test, as this will increase their chances of getting pregnant.