How to Determine the Sex of a Lovebird
There are services that will test your bird's DNA. By doing DNA you can determine Lovebirds sex.
Female lovebirds need more width in the pelvic region in order to pass eggs through it. This means that you may be able to determine a male from a female by comparing the width of several lovebird's pelvic bones.
Take the bird into your less-dominant hand so that it is held upside down and its head is away from you. Take the pointer and middle fingers of your dominant hand and gently feel around the pelvic area of the bird. You should be able to feel the pelvic bones through the feathers and skin.
Some people argue that female lovebirds are generally smaller than male lovebirds. This is only visible in certain breeds of lovebirds.
Some people also assert that a female lovebird's feet are perched wider apart than a male's feet. This has to do with the assumption that a female's pelvis is wider than a male's.This depends on the species.
Unlike many other types of birds, most types of lovebird coloring does not differ based on sex. There are some exceptions, however, such as the Madagascar lovebird. The male Madagascar lovebird has grey on its head, while the females are solidly colored green.
Keep in mind If lovebirds are kept in a pair, they tend to form an intense bond. It does not matter what the sex of the birds are. Birds kept together will become a unit. Bonded pairs of the same sex are even known to work on nesting together.