Male VS Female Pugs
Regarding care, there are a few issues. A female will enter heat unless you have her spayed. It is best for both you and your Pug if you do have this procedure done.
Do keep in mind that having a dog spayed is a bit more expensive than having a dog neutered. If you do not have this done, approximately twice per year she will enter heat.
This can cause some issues such as problem of her bleeding in the home and male dogs running after her.
The biggest difference with females is that those that are not spayed will have heavy sheds - and this breed is already a super heavy shedder - after each heat cycle. It should also be noted that there will be a 'blowing of the coat' after a pregnancy.
When Pugs are fixed, there is no difference in the amount of hair loss and female Pugs will not shed more than males.
When you have a male, he may hump just about everything in existence until you have him neutered. This can make for some rather awkward and embarrassing moments.
Regarding temperament, while every dog has their own personality, it can be said that in general males and females are different. Male Pugs may be a bit defiant during their teenage years, which will be from 6 months old up to 3 years old.
Aside from this time, the male Pug is usually a bit more laid back than the female. The female may be a bit easier to train; however both genders can be trained when you follow strict guidelines.
Before you make a decision, be aware of the other dogs in your neighborhood. If there is a male dog that is left to roam around or immediately next door to your home, you will want to understand that a male Pug may be a target for fighting.
Regarding health, the most significant gender specific health issues that are considered serious or fatal are directly related to reproductive elements. Without being spayed a female may develop ovarian cancer. Without being neutered, a male may develop testicular cancer. Both genders are prone to hip, knee and respiratory issues and this does not occur more often in one gender over the other.
Regarding life span,
females - in general - live slight longer than male Pugs. Females live an average of 13.2 years compared to their male counterparts with a life expectancy of 12.8 years.