many of the misconceptions rose against islamic legislation claim that it is inadequate for the modern age. for example, they claim that the verse "and divorced women shall await by themselves for three periods" (al bakara 228) is no longer applicable as medical analysis can easily tell if a woman is pregnant or not. so, for them, there is no need to wait three periods to be sure.
latest studies refuted this misconception discovering that semen contains 62 types of proteins, and those proteins formula changes from man to man. so every man leaves some kind of protein print into his wife's womb. if a woman marries directly after divorce, she might get uterine cancer as a result of the existence of more than one protein print in the womb. studies also showed that the first menstruation after divorce eliminates 32% to 35% of that print, the second menstruation eliminates up to the range from 67% to 72% and the third eliminates up to 99.9% and only then a womb gets ready to receive a new protein print.
considering widows, almighty allah says: " and the ones of you who are taken up, (i.e., those who die) and leave behind (them) spouses, (the spouses) (i.e., the widows. the following verb is in the feminine plural) shall await by themselves for four months and ten (days)" (al bakara 234). studies conclude that a widow's grief and depression makes the print more stuck to her womb and so she needs one more period to be completely eliminated just as allah said.
in conclusion, all what we should do is to glorify allah and reason the verse " and in your selves; do you then not behold?" (ath-tharyat 21)