Ministers have agreed to lobby the European Union over the controversial "tampon tax" - avoiding a potential third Parliamentary defeat in a single night.
Labour had won cross-party support for an amendment to the Finance Bill which would have forced ministers to challenge the EU over VAT on women's sanitary products.
But the Government managed to get its bill through with a majority of 18 after Treasury minister David Gauke pledged to take the matter to the European Commission.
Women pay a 5% levy on tampons and sanitary pads because they are classified as "non-essential luxury items" by the EU for VAT purposes.
The UK already has the lowest rate among the 28 member states - among which the average is 17%.
Mr Gauke stressed the law was unlikely to change.
He told the Commons: "Without that agreement (of all 28 member states), we are not permitted to lower rates below 5%.
"Nonetheless, as this debate illustrates there is very considerable cross-party support for the UK to abolish VAT on sanitary products.
"To that end, I undertake to the House I will raise this issue with the European Commission and other member states setting out the views reflected in this debate - that it should apply a zero rate to sanitary products."
But he added: "I do not want to conceal from the House we don't have flexibility in this circumstances, nor do I want to conceal from the House the challenge that would exist in reaching agreement.
"Other member states do take a different approach ... I don't want to pretend this is a formality."
The amendment against what has also been called "vagina added tax" was tabled by Labour's Paula Sherriff and was supported by eurosceptic Tories who saw the issue as an example of the loss of UK sovereignty.
Ms Sherriff had told the Commons the 5% VAT charge on tampons "hits the poorest the hardest".
"Imagine, for example, being homeless when that time of the month comes," she added. "Think what it's like to face a period without even having a bathroom."
Campaigners say the average woman will spend £18,450 on sanitary products over the course of a lifetime, of which £922 is tax.
Most goods and services have a 20% VAT rate, with some items having a reduced rate of 5%.
Essential goods such as food, drink and children's clothes have a zero rate of VAT.
The concession by ministers came just hours after the Lords twice defeated the Government over tax credits .