There's no simple answer - it totally depends on your individual circumstances. If you have to do a tax return then you can use your existing password to log into the beta government system and see how many years NI contributions you have credited, what pension you will get and whether it's worth making voluntary contributions. (For those of us who RE, it often does work out to be a good idea to make the minimum self-employed contribution, even if the business is in name only...) You can also get a detailed written statement. Bottom line, if your husband is below the 35 year figure and is already retired, it's probably worth doing.
Anyone who plans to retire in the UK should take the time to get to grips with the complexities of the state pension system, particularly if you plan to do something unusual like retiring early.
Steve Webb, the former pensions minister quoted, is one of those rare people in politics who has a very detailed understanding of the thing he was in charge in, and tried his best to make changes which took a long-term view and treated people fairly. A real shame that he is no longer in post, but I would take anything he say on pensions seriously.