That is an OLD rule!! It used to be that a member that got married or became pregnant was not allowed to be an active member of the chapter. This was changed, if I'm not mistaken, at the 1993 convention. These members may now remain active OR may go alumnae under the "special circumstances" section of Membership Eligibility. I hope that answers you question.
Loyally,
Tracey
Zeta Alpha Chapter Advisor