Generally, the types of leave differ from establishment to establishment depending on the leave provisions either contained in the service regulations of the individual establishment or the establishment-specific employment law applicable.
When and to what extent a newly appointed employee can avail of such leave cannot be specifically stated for the reason that any leave can not be claimed as a matter of right. Again the scale of each type of leave and the manner of accrual are different too. For instance, Casual Leave is fixed as a certain no per year and the extent of its availment at a stretch is a matter of discretion of the employer whereas EL/ PL is earned by the employee by working for certain minimum no of days in the current year to be availed of only in the succeeding years subject to prior application by the employee and sanction by the employer. Normally, new employees, during their probationary period, are allowed CL only on pro rata basis.
To my knowledge, there is no such leave called as " Medical Leave " either in industrial employment or State employment. Of course there is sick leave for the purpose of recuperation from sudden illnesses which last for a day or two and may not require medical evidence,if any in the opinion of the employer. Naturally sudden illnesses can not be predicted and the employer can not be indifferent so as to deny it outright merely on the length of service. In Government Service both at the Central and State, there is a special type of leave called as Unearned Leave on medical grounds subject to a maximum limit during the entire service. In the absence of such a leave provision in any private establishment, medical leave naturally would refer to the leave on loss of pay availed of by the employee due to any chronic disease or personal accident supported by proper medical evidence so that his lien on employment is not lost.
There is another type of leave called Sabbatical Leave implying extended absence from work place by certain employees for achieving life goals. It can be granted to employees to pursue higher studies or to acquire new skills. It can be a paid or unpaid leave at the discretion of the employer depending on the relevance of the course of study to the post held by the employee and the assurance of the employee of a specific length of service in the organization post the sabbatical leave sanctioned. Here, it is to be noted that such leave is generally granted to long serving employees only and not to new entrants.