In my job as a firearms instructor, both NRA and State certified, I am often asked what firearms are the best choices for females. This comes both from females as well as for males looking for a handgun for that special woman in their life.
Here is what I tell them
Who says women are more delicate?
Women may be the fairer sex but there is nothing out there that says they are too delicate to use a handgun. On the contrary, I have instructed several female officers with my agency and they often outshoot the average male officers in combat handgun qualifications. Granted, I have had a few who struggled and a few over the years that I recommended after intensive one-on-one remedial training not to carry a firearm in a law enforcement scenario. However, I have had the same bad luck with roughly the same percentage of male officers. Not everyone is cut out to carry a firearm and it makes no difference what plumbing he or she has. With that in mind you can throw any preconceived notions right out the door. Everyone is different and until you get them some training and see what they can do, you just don't know.
Some of the best competitive shooters for the past 150-years are female. If you don't believe me, Google Annie Oakley, Tori Nonaka, or Julie Golob.
The "makes a good woman's gun" cliche
The standard answer for recommending firearms for women is that a J-frame .38 or a .380 Auto is the way to go. The concept is that the snubby revolver is extremely simple to master, with a 'point and click' type of philosophy. The thinking behind the .380 is that it is invariable a super small frame semi-auto such as a Ruger LCP or a legacy Walther PPK and small equals more controllability and an easier grip on small hands.
(Photo from Lindsay McCrum's new photo book Chicks with Guns. It shows Ellie of Merced, California with her Taurus Titanium .38. Ellie says, ""I bought my gun - the one in the photograph - at the local gun store in Merced, California. It's a .38 titanium revolver made by Taurus. My hands are not strong enough to pull certain guns back, so I need a revolver. It's very lightweight and easy to use.... When I was mayor, I couldn't practice as often as I wanted to, but now that I'm no longer mayor I go a lot more often. The girls usually go on Tuesday nights. We go to our local gun range, hook up our targets, and then all go down and see who's the best shot.")
Well the problem with both of these cliches is that in most cases the .380 ACP in a small frame pistol and the snubby .38 both suffer from excessive muzzle flash, muzzle flip, and are downright unpleasant to shoot. I am a big guy (6'3", 275#) and I would much rather shoot a longslide .45 than a .380, it's just more enjoyable, more accurate, and has a faster follow up shot. I have personally experienced multiple females who share the same feelings. A nice compact 9mm such as a Glock 19 or SIG P229, or even a subcompact Glock 26/Ruger LC9 etc. have much better ergonomics and control with the benefit of increased ballistics envelopes and dual stack magazines.
Sometimes even with reduced recoil loads, full powered handguns such as .380/.38SPL and above are still too much for very small statured people or those with hand control issues such as repetitive stress injury, arthritis, and carpal tunnel, to use comfortably. In these instances, if a handgun is still sought after and the person is dedicated to the use of one, its permissible to look into a smaller caliber such as .22WMR/.22LR, .25ACP, etc. for personal defense.
With increased loads for these mouse guns such as Hornady's Critical Defense, and prospect of some of these lightweight new pistols having very large magazine capacities, this is not as farfetched as it had been in the past.
Therefore, in the end, my recommendation is the same one that I give to a man, "Carry the largest caliber handgun with the largest magazine that you feel comfortable with, can afford, and enjoy to shoot."