Seven days before re-marriage

Hi,

After a man and woman decide to wed, the woman waits for shivah nekiyyim, a seven-day period in which she makes sure that she is not bleeding as a niddah, before they can get married.

In certain communities, there is a custom that a man who believes he is dying issues a bill of divorce [to prevent a chalitzah obligation for his wife], with the understanding that they will re-marry should his health improve. In such a case, there would be no need for the seven-day waiting period.

(Rav Moshe Feinstein, Igrot Moshe Yoreh Deah 1:86)

Have a great day,
Mordechai