1. Provisions contrary to the principle of equal treatment shall include those based on sex, either directly or indirectly, for:

(a) determining the persons who may participate in an occupational social security scheme;

(b) fixing the compulsory or optional nature of participation in an occupational social security scheme;

(c) laying down different rules as regards the age of entry into the scheme or the minimum period of employment or membership of the scheme required to obtain the benefits thereof;

(d) laying down different rules, except as provided for in points (h) and (j), for the reimbursement of contributions when a worker leaves a scheme without having fulfilled the conditions guaranteeing a deferred right to long-term benefits;

(e) setting different conditions for the granting of benefits or restricting such benefits to workers of one or other of the sexes;

(f) fixing different retirement ages;

(g) suspending the retention or acquisition of rights during periods of maternity leave or leave for family reasons which are granted by law or agreement and are paid by the employer;