One of the factors in where a person puts on weight is gender. The other is body type.
In a person who starts out at his perfect weight and then starts to gain weight, where the weight shows up on most women first is below the waist and above the knees. Where it most often shows up first on men is around the middle. With enough weight gain the weight will eventually "move beyond" where it first showed up and begin to show up more obviously everywhere.
Where body type plays a role is that, man or woman, some people have more of an endomorph body type while others' body type if more mesomorph, regardless of gender. Endomorphs tend to gain weight in the pattern that women do. Mesomorphs tend to gain weight in the pattern that men do. People with extra weight are often said to either be "apple shaped" (like men and mesomorphs) or "pear shaped" (like many women and endomorphs). People can also have an ectomorph body type, and they are the people who tend to be naturally slender and generally not gain weight very easily.
With individual genetic make-ups, however, people may see variations in these common patterns of weight gain. In spite of the fact that women are often pear-shaped (because of their child-bearing role), we've all seen women who are more "apple-shaped".
The person who gains only a small amount of weight may mainly notice it wherever that first place for it to appear is, but more weight gain would eventually result in weight becoming more obvious in other areas.