Women in their 30s are, numerically, the biggest single group leaving teaching, according to new analysis seen exclusively by the BBC.
More than 9,000 of them are leaving teaching in England in 2022-23, compared with more than 3,400 people of the same age.
In a report called Missing Mothers, researchers called for more family-friendly policies to stop the exodus.
The Labor Government has promised an additional 6,500 teachers.
Retaining teachers remains a challenge. In a profession dominated by women, the report â released on Friday â found workloads, striking a balance between teaching and family, and mothersâ salaries, all need to be addressed.
âTough decisionâ
The New Britain Project, an independent think tank, conducted detailed interviews with 383 women who had either stayed in teaching or left the profession.
Cara Carey is one experienced teacher who stopped teaching, in her case after the arrival of her second child.
âI just donât feel like Iâm a good mother, or a good teacher,â she told the BBC.
Ms Carey teaches music and science, and is also head of sixth form, at the secondary school.
He wept as he explained the âvery difficult decisionâ to stop teaching.
She now works for a charity, which means she can organize sports days, Christmas events or school trips for her son Finley, six, and will be able to do the same with Rafi, who is five.
There is currently a severe teacher shortage in England in most secondary subjects. this week, paid review bodies The report warned that only three subjects have been recruited in sufficient numbers from teachers to the initial training.
A new analysis found women aged 30-39 have been, numerically, the largest group of teachers leaving each year since 2017.
While the number of people in their 30s leaving is lower, the proportion is greater, because the number is smaller.
The data shows that 57% of female teachers between 30-34 have a dependent child under the age of 19, and 77% of female teachers aged between 35-39 have a dependent child under the age of 19.
Currently, many other graduate professions offer hybrid work, with some days at home, which has led to warnings about teacher recruitment crisis.
One of the obstacles is the motherâs salary, which according to the national situation of most schools in the UK is poor compared to other jobs.
Teachers get four weeks at full pay, then two weeks at 90% of pay, then 12 weeks at half pay plus statutory maternity pay.
NHS maternity conditions provide 18 weeks with full pay, civil servants in the Department of Education are entitled to 26 weeks with full pay.
A range of 18 -26 weeks with full pay is seen in both the public and private sectors. Tesco and Sainsburyâs offer 26 weeks with full pay, while Lidl has extended its offer to 28 weeks.
Laura Nwanya said it was ânot an optionâ to have a year off when her children were born, due to financial pressures.
When Eden, now seven, was born, she had to go back to work before she was four months old â and could only take a few more months off with Myles because she inherited money.
Mrs Nwanya explained her âguiltâ for leaving early at 7.30am to go to school to teach other peopleâs children.
As a mother, she often misses birthdays and sports days and says that âitâs really sad that I canât walk to school in the morningâ despite changing schools to find a more flexible job.
The report on Friday called for a number of measures, including giving teachers the same maternity pay as civil servants in the Department of Education.
It also highlights the need for better individual support for returning mothers, and recommends that teachers be given priority for childcare places on school sites.
The most important shift is to allow more flexibility in work patterns, which economists have identified as one of the biggest challenges.
âWaste of talentâ
Some academy trusts have tried to make teaching more interesting.
Dixons Academies Trust said it wanted to offer two nine-day weeks to teachers at 17 schools in the north of England.
In Cambridge, Linton Village College is part of a diverse group of academy schools that have implemented flexible working.
Over a third of teaching staff have arrangements such as slightly different start or finish times, and work part-time.
It uses specific timetabling software to manage requests.
The schoolâs headteacher, Helena Marsh, said it was what was needed to stop the âwaste of talentâ caused by the loss of experienced female teachers in their 30s.
Schools face challenges, not only from the lack of teachers but also tight budget â but teaching union ASCL said addressing the issues raised by the report was âvitalâ.
On mothersâ pay, the Confederation of Schools Trust â which speaks for academy schools â said the challenge was ânot the will to do it, but the financesâ.
This week, the government made a small move for greater flexibility â calling on all schools, rather than just a few, to allow teachers to do lesson preparation time at home.
But Anna McShane said much more is needed to keep experienced teachers, because âif we donât focus on retention, we fill the leaky bathâ.
The government says it has awarded 5.5% to teachers, and explains that teacher lesson preparation time can be spent at home as a start.