Officials at Citi Bike say they are attracting a greater share of women than the citywide rate of female cyclists — about 21 percent, according to a study from Hunter College. The bike-sharing service is looking at more than just the safety concerns that seem to nag more at women than men, who insurance actuaries long ago concluded are more likely to engage in risky behavior, such as not wearing a bike helmet.

And there are other perceived obstacles, not unique to women but more commonly cited by them: They cannot ride with small children. They think the cost — $149 for an annual membership or $9.95 for a day pass — is too steep, especially on top of a subway pass. And they worry about arriving at work sweaty.

“I wouldn’t want to be gross the whole day,” said Maeve McCarthy, 21, an intern at an interior design firm in Manhattan, who has not tried Citi Bike but said she would consider taking a nice ride through Central Park, if not commuting to work from Brooklyn.

The report by the Rudin Center said Citi Bike’s planned expansion this year to Long Island City in Queens and further into Brooklyn in Bedford-Stuyvesant and Greenpoint could help diversify its customer base, bringing in less wealthy riders and more women. The current 330 or so bike stations are in Manhattan below 61st Street and in a few Brooklyn neighborhoods near Lower Manhattan, many of which are more affluent.

Women have avoided riding in bustling Midtown Manhattan and often stick to less chaotic neighborhoods on the Lower East Side and in Brooklyn, the report said.

Citi Bike’s gender gap is part of a broader pattern among cyclists across the country; bike-share systems in Chicago and Washington also have more male riders. To woo women, Citi Bike is hosting rides with women’s cycling groups and trying to make cycling seem stylish.