Avril Lavigne is reportedly experiencing ''health issues''.

The 'Complicated' singer - who is married to Nickelback frontman Chad Kroeger - hasn't been seen in public since September and has apparently told a Twitter fan that she is unwell with an undisclosed problem.

In a direct message to AvrilMusicChart, she wrote on Sunday (07.12.14): ''I feel bad because I haven't been able to say anything to the fans to let them no why I've been absent.

''I'm not feeling well. I'm having some health issues. So please keep me in your prayers. (sic)''

Though Avril hasn't commented on her problems or confirmed the legitimacy of the messages, she publicly responded to the Twitter account after they sent well wishes, writing simply: ''thank you.''

The 'Girlfriend' hitmaker's health woes come a few months after speculation her marriage to Chad - who she married in July 2013 - was in trouble.

However, the 'This Is How You Remind Me' rocker later laughed off the reports, which were fuelled when he missed Avril's 30th birthday party, but admitted even his family had worried about the status of their relationship.

The 39-year-old rocker said: ''You know my dad calls me up and he's just like, 'I haven't slept in two days, what's going on?' I'm like, 'Dad you're not buying all this c**p are you?' You know, I get to hear all the rumour mill stuff. So it's, it's...I find it very amusing.''