Susan Hibdon opened her front door and saw nothing but white.

It was a day that would go down in tabloid headline history after schools Chancellor Carmen Fariña declared it “absolutely a beautiful day,” despite a forecast calling for 10 inches of snow. For Hibdon, a Brooklyn high school teacher, it was memorable for a different reason. It was exactly six weeks after she had given birth, which meant it was time to go back to the classroom.

She kissed her infant goodbye and headed into the wet February weather.

“If you want to pay your rent, you have to go right back to work,” she said. “That’s not just bad for the mother who just gave birth. That’s bad for everybody.”

New York City teachers have no paid maternity or family leave, a policy that takes a toll on teachers’ paychecks and creates deep gender inequity in an education workforce that is about 77 percent women.

Hibdon and fellow teacher and mother Emily James recently launched an online petition calling on the United Federation of Teachers to negotiate for paid leave, which is not included in any of the city’s contracts with unionized workers. Almost 78,000 people have signed on, and the women will present their request at the union’s executive board meeting on Monday.

“I think the irony of it sticks out to many people: These are women who are paid to raise children and they aren’t paid to raise their own children,” Hibdon said.

As it stands now, teachers who want to take paid time off after having a baby must use their sick days. The policy only applies to birth mothers, putting a strain on those who become parents through adoption or surrogacy, and fathers who want to take a leading role in the earliest moments of parenthood.

“We talk so much about parents being active in their child’s education,” said Rosie Frascella, a teacher who has also pushed for paid leave policies. “Well, let’s let teachers be active in their child’s education.”

For teachers, the policy packs a financial blow on multiple levels.

If a mother wants paid time off after giving birth, the only option is to use sick days. Women are limited to six weeks of sick time after a vaginal birth, and eight weeks after a C-section.

Teachers earn one sick day per school month. In order to save up for an eight-week leave, a teacher would have to work about four years without using any sick days.

Many women haven’t accrued that many days, so they can “borrow” sick days they haven’t yet earned. Teachers run into problems, though, if they actually get sick — or their children do — since they can only borrow up to 20 sick days. Once they hit that number, any additional time off is unpaid. And if a teacher leaves the education department, she must repay any sick days she borrowed.

Hidbon learned that the hard way. She has three children — and precious few sick days in the bank. Hidbon remembers a time that she completely lost her voice, but still had to go to work.

“No one could hear me. I had to conduct my entire class writing notes on the board,” she said. “I’m supposed to be teaching and I can’t do my job because of the way the system is set up — and my students are getting the short end of the stick.”

The crunch for sick time could lead to a financial blow later in a woman’s career. Teachers are allowed to accrue up to 200 sick days, and receive a payout for unused time when they retire. The city could not provide numbers for how many sick days men versus women retire with. But it makes sense that men would rack up far more since women with children are more likely to get stuck with a negative balance.

James, a Brookyln high school teacher and co-starter of the online petition, still has a negative balance of 16 sick days — almost three years after giving birth. The problem is compounded by the fact that women are more likely to take time off when a child is sick or there are other family obligations, a pattern that is seen in professions across the board.

“There were many times when I was so sick at work the kids were like, ‘Why are you here? Miss, go home,’” she said. “But it costs a lot of money to stay home.”

Even when women don’t have to borrow sick days, they can still lose financially. The city only allows women to use up to eight weeks of their banked time. Any additional days off are entirely unpaid.

Amy Arundell, a former director of personnel for the UFT, said many mothers stay home longer because of the federal Family and Medical Leave Act, which provides job protections for 12 weeks of leave.

“The people who don’t take 12 [weeks] obviously have real financial commitments” that make taking unpaid time off impossible, she said.

Women who take that time get hit with a double-punch to their salaries. Because of the way summer pay is calculated, unpaid time off results in a smaller summer paycheck, too. Arundell said the hit is usually equivalent to one paycheck.

Same sex-couples and those who become parents through surrogacy or adoption face many of the same financial setbacks, since only birth mothers are allowed to use sick time after having a baby.

After years on a waiting list, Seth Rader and his wife had only weeks’ notice that their adoptive baby was on the way. Since his wife was in grad school, the couple decided Rader would stay home with their new son — even though Rader, a Manhattan high school teacher, is the primary breadwinner at home.

“In a lot of ways, I’m much more bonded with him as a father, and him to me,” Rader said. “Are we really in a place where we want to discourage fathers from taking that role?”

At the time, the couple were saving for a down payment to buy a place of their own. After the expense of Rader taking off from work, they still are.

“I think all of this has to be affecting the sustainability of teaching,” he said. “If we create a system where people can’t imagine being teachers and parents at the same time, then that’s a loss.”

When it comes to the push for family leave, teachers have been left behind even as strides are made elsewhere. New York State recently passed a mandatory paid leave policy that will cover private employees. Last winter, Mayor Bill de Blasio signed a paid leave act for city employees.

But that benefit isn’t extended to workers with unions, like the United Federation of Teachers. Currently, no union in New York City has paid maternity leave, according to a city spokeswoman.

Teachers across the city are fighting to change that. The petition started by Hibdon and James calls on UFT President Michael Mulgrew to “fight for our teaching mothers.”

“They’re supposed to really care about what teachers are struggling with and they’re our voice,” James said. “I just wish that they would take this seriously.”

Both the city and the United Federation of Teachers say they have held talks to extend similar benefits to teachers. In an emailed statement, Mulgrew called family leave “an important issue for the UFT and its members.”

“In our talks so far, the city has failed to come up with a meaningful proposal,” he said.

In an article published in the UFT journal, which ran shortly after the city passed its parental leave policy, the union pointed out that gaining that benefit came at the cost of a scheduled raise for managers and fewer leave days for veteran employees.

According to the article, Mulgrew said he “looked forward to negotiations with the de Blasio administration for an appropriate way to expand parental benefits for UFT members.”