Looking on from a distance I vowed that this would not happen to me: I was determined that the fact that I had given birth would not divide me and my single buddies.
But now, several years on the same seems to be happening to me. I do still have non-mummy friends but I rarely see them. I don't tend to have coffees in town with friends, and the last time I had a night out with my old friends was at my friend Elaine's 30th two years ago.
I had a hard pregnancy with my daughter nine years ago, and a terrible birth. So a few months down the line, when I was feeling up to it, I was keen to start socialising again. After all I had just had nine months of not feeling well enough to see anyone.
Determined that having a baby would not change my life completely, I made an effort to keep in touch and at first would make arrangements to go shopping, leaving the baby with my husband.
I think the change occurred as I become more confident as a mum. While at first the concept of hauling a buggy on and off a bus or train was quite daunting, once you get used to it, it becomes second nature.
And by this stage my daughter had turned into an easy baby. I remember on a couple of occasions going for lunch with a friend, where my daughter slept all the way through the meal. It soon became natural to take her with me.
Getting out on your own is hard when you have small children. Or perhaps it is just that taking a small person with you seems so much easier than leaving them. But for those without children it is hard to understand.
My friend Elnette agrees with me and has found friendships change. She says: "One of my oldest friends, who has not yet had any children, came to visit when my daughter was only a year old. This friend likes to have my full attention and wanted to spend many hours of every day just talking. She would talk while I would be distracted by looking after daughter. I was irritated and she was frustrated that I couldn't talk like I used to about ourselves and our thoughts on life. My priorities had changed and my time was no longer solely my own. That was four years ago and we are still friends but I go to see her on my own for a visit."
But perhaps as Elnette has done, it is better to adapt friendships. My friend Cathy has stayed in touch with friends from her pre mummy days and counts these friends as her close friends, closer than those with children. "Perhaps it is a case of needing to be more selective and making more of an effort with closer friends" she suggests.
There are key times in a person's life when as well as making new friends, some current friendships are shed. Leaving school, finishing university, getting married – they are all events in our lives which potentially take us down different paths from our friends.
My youngest child is nearly two and I am currently planning a weekend away visiting two of my oldest friends who I have kept in touch with but due to distance haven't seen much of for the past 10 years. I have also started socialising with new friends, some mums, some not.
Have you kept in contact with pre-children friends?
Or does your life slowly become more centred around children and local activities?