Some people are afraid of having the hero or protagonist rescue their love interest because it reinforces the old stereotype of a woman needed to be rescued by a man.
I may point out that there is a lot of truth in the old stereotype of a woman needing to be rescued by a man. Countless millions of men, women, and children have been in danger in history and each of those countless millions of endangered persons needed to be rescued by one or more men, women, children, or animals. Certainly many millions more people needed to be rescued than actually were rescued, so if someone is rescued there seems to me no reason to quibble about who rescues them.
And there is no shame in a man, woman, or child in a dangerous situation needing to be rescued by someone bigger and stronger than them, or even needing to be rescued by someone smaller and weaker than them.
For example, in 272 BC, in street fighting in Argos, an Argive warrior was losing to King Pyrrhus of Epirus when the warrior's old mother on a rooftop grabbed a heavy roof tile and flung it down on Pyrrhus's head. Pyrrhus fell down, living or dead, and another Argive warrior beheaded him.
At the Battle of Antietam, September 17, 1862, a officer of Battery B, 4th US Artillery was wounded and the much smaller 15-year-old Bugler John Cook helped helped him to the rear. When Cook returned to the battery he found an abandoned cannon and loaded and fired it by himself.
At the Battle of the Rosebud, June 17, 1876, Sergeant John Van Moll of Company A, Third US Cavalry, "a brave and gigantic soldier", was so eager to fight that he accompanied a mounted charge by the Crow and Shoshone allies against the Sioux and Cheyenne while he was on foot. After fighting for a while, the mounted warriors withdrew, as was their custom, and Sergeant Van Moll was left alone and on foot and easy pickings for the Sioux and Cheyenne.
Major Randall and Lieutenant Bourke, who had probably not noticed him in the general melee, but who, in the crisis, recognized his stature and his danger, turned their horses to rush to his rescue. They called on the Indians to follow them. One small, misshapen Crow warrior, mounted on a fleet pony, outstripped all others. He dashed boldly in among the Sioux, against whom Van Moll was dauntlessly defending himself, seized the big sergeant by the shoulder and motioned him to jump up behind. The Sioux were too astonished to realize what had been done until they saw the long-legged sergeant, mounted behind the little Crow, known as Humpy, dash toward our lines like the wind. Then they opened fire, but we opened also, and compelled them to seek higher ground. The whole line of our battalion cheered Humpy and Van Moll as they passed us on the home-stretch. There were no insects on them, either.
https://www.astonisher.com/archives/museum/rosebud/john_finerty_rosebud.html1
Also at the Battle of the Rosebud June 17, 1876, a Cheyenne warrior named Chief Comes in Sight was wounded and was left behind by retreating warriors. His sister, Buffalo Calf Road Woman (c. 1844-1879) rode out to him, picked him up on her horse and rode away with him to safety.
Those few examples I could think of at the moment show that chance events can put even a brave and competent warrior in a situation where he needs to be rescued by someone, and sometimes that someone might even be smaller and weaker than them.
(added 09-12-19. There actually have been all female military combat units, including the dreaded Dahomey "Amazons" who fought with spears and swords as well as with rifles, Paraguayan female units in the War of the Triple Alliance, and Russian female units in World War II. So historically there have been military situations with rather increased probability of females rescuing males who were on their side.)
I can also point out that the original question supposes that the protagonist and/or hero of the story will be male and the love interest who the protagonist and/or hero might need to save during the story would be female.
But it is perfectly possible to write a story with a female protagonist, and even a story where a female protagonist rescues her boy friend or husband from danger. J.R.R. Tolkien's Beren and Luthien (2017) contains various versions of the story of Beren and Luthien written over several decades starting about 1920, and in them Luthien sometimes rescues her lover Beren from various dangers.
So a story where a women rescues a man from danger would not exactly be a brand new idea in 2019.
Furthermore, it is perfectly possible for a real person or a fictional character to fall in love with a person of the same gender as themselves, and thus possibly rescue their lover of the same gender.
For example, in the 4th century BC the elite military unit of the Greek city state of Thebes was the Sacred Band, composed of 150 pairs of male lovers. It fought at the Battle of Tegyra in 375 BC, where they defeated a Spartan force, the Battle of Leuctra in 371 BC, which was a historic defeat for the Spartans, and were wiped out at the Battle of Chaeronea in 338 BC. I imagine that some members of the Sacred Band saved their lovers in battle.
Furthermore, while the vast majority of humans are either male or female, a small proportion of humans are not. I know of at least one military unit composed of members of a "third gender", the eunuch bodyguards of the eastern Roman or "Byzantine" Emperor in the 6th century.
And in fantasy and science fiction stories it is possible to have nonhuman alien protagonists who might not be either male or female. And in science fiction stories there can be intelligent robot and computer protagonists who may be gender less.
