In the back of the Chumash Shai LeMorah, a list and hierarchy of the the people who are obligated to receive an Aliyah to the Torah. He adds parenthetically as follows:
It is written in the Sefer Avodat Hakodesh of the Chida Z"l that there is a custom in Eretz Yisroel that someone whose wife enters her 9th month of pregnancy should be careful to do the Mitzvah of Opening the Ark. This is a nice custom and has Kabbalistic support.
Here is a link to the Chida (Mareh B'Etzbah 3:90).
Here is an article that extensively covers this topic and brings many places that discuss it.