create ordinal array for multiple groups

I need to categorize a dataset according to different groups. For the example below, I want to create an ordinal array that differs by gender. I first subset the data by gender and then use the ordinal function. My questions are:

1. Is there another way to join the subsets so that I don't get duplicate _Right and _Left variables (last line of code)?
2. Is there an easier way to do this without having to create subsets of the dataset?

I am using Matlab R2012b version.

load hospital;

subset_m=hospital(hospital.Sex=='Male',:);
subset_f=hospital(hospital.Sex=='Female',:);

edges_f=[0 20 max(subset_f.Age)];
edges_m=[0 30 max(subset_m.Age)];

labels_m = {'0-19','20+'};
labels_f = {'0-29','30+'};

subset_m.AgeGroup= ordinal(subset_m.Age,labels_m,[],edges_m);
subset_f.AgeGroup = ordinal(subset_f.Age,labels_f,[],edges_f);

    joinFull=join(subset_f,subset_m,'LeftKeys','LastName','RightKeys','LastName','type','rightouter','mergekeys',true);