Actress Linda Cardellini feels "lucky to be alive" after she nearly died in childbirth last year (12).

The former Er star was hospitalised with pneumonia and began suffering severe complications when she hit the nine-month mark while pregnant with daughter Lilah-Rose, her first child with partner Steven Rodriguez.

Cardellini then had to undergo an emergency Caesarean section in February 2012 when the time came for her delivery.

She tells, "It was a very traumatic period. I had a really scary pregnancy and a very difficult delivery. My daughter and I are lucky to be alive... (The baby's) heart rate dropped and she had the umbilical cord around her neck. We had to do an emergency C-section. It was very intense and scary."

After Lilah-Rose was born, Cardellini then struggled with a thyroid issue: "I had to go on medication and because of that my weight fluctuated up and down in a really erratic way. It was hard to get a handle on it."

The star has returned to the spotlight with a new role in Mad Men, and feels fortunate to have bounced back from her health scare.

She says, "I'm so grateful that my daughter is alive and so thankful that we've all come out of it. We often forget how dangerous childbirth is... I never realised what an enormous amount of love I could feel for someone. Suddenly now that I have this beautiful, innocent creature to protect, I've become more aggressive and become much more of a mama bear."