When I had my son I was lucky enough to have a few friends who were all at a similar stage of life as me. We were all married, settled down and either already had babies, were trying for babies or were planning for babies.
However, there were one or two friends who did not fit into the latter categories. Because they were such good friends, I didn't think that a baby would surely come between us.
How wrong I was.
One of my closest friends very slowly slipped out of my life as my son grew. It became apparent very quickly that we no longer had much in common and our priorities were now completely different.
For a long time I was bitter and resentful. After all, having a baby hadn't changed the person I was. I was still 'me', just with a little person attached now.
But over time I accepted that, while it was sad, it's a common occurrence as life takes us all on separate paths.
And I know I am not alone.
Jayne Turner* has experienced a similar situation with a good friend of 14 years.
"Before I had my daughter we would catch up at least once a week, and exercised regularly together as well. But after I had Jess we stopped catching up as much, as she was going through a marriage break up, and I couldn't string a sentence together with a newborn."
Turner said that over time the friendship became more and more effort. The small idiosyncrasies she used to overlook began to irritate her.
"She always used to forget her wallet so I'd end up paying, she would borrow clothes and not return them, and she was always late," she says.
"I began to resent her. I was on one wage now so why should I always have to spot her for cash on our catch ups? And if I could get somewhere at an agreed time with a newborn to organise, why couldn't she?"
The turning point came when Turner waited for her friend for 90 minutes to go and see a movie. Since then, she has distanced herself and screened her calls.
"I think having children has taught me that not all friendships, even long-term ones, are supposed to be forever - and not all friendships are healthy for me," she says.
"Some friends are only meant to be in your life for a period of time, and once you have children and your perspective and priorities change, those old friends and their values or priorities don't necessarily match yours anymore."
Melissa Henry* can relate to the other side. She admits that when a good friend got pregnant, she started to slip away.
"I felt like what was happening in my life was all so boring and pointless. She was growing a baby and having this amazing experience, and I was single and going out and doing all the same things," she says.
"I saw her a few times after her son arrived, but I felt hopelessly out of my depth. We just kind of drifted apart - she was so busy getting used to her new life that I kind of used that as justification. I still feel bad about it."
Parenting expert Dr Karen Phillip says it's common for friendships to change this way.
"For a friendship to work, there must be some give and take, and we need to show an interest in each others lives," she says. "The difficulty comes when we have a baby because while we still understand our friend's life, they can no longer understand ours."
Phillip says this is one of the most common reasons for a friendship breakup after a baby. She also says it stems from us not having as much time to invest in our friends and not being as interested in their issues or events as we once were.
So, as the new parent, is there a way we can save a flagging relationship?
"If you can remain interested in your friend and ensure you spend some quality time with them to listen, support and laugh with them, this could be all it takes," advises Phillip. She adds that you may need to expand the conversation to outside the baby world.
On the flipside, Phillip says that it's important to know when to call it a day.
"If a friend seems continually dismissive of you, your baby stories or current experiences, this may be a red flag to the friendship."
Despite this, the fading of a friendship because of a baby doesn't always mean it's completely the end, as Karen Rings* explains.
"Charlotte and I were really close friends and even during my pregnancy we still saw a lot of each other, although boozy nights out dancing turned into cups of hot chocolate in cosy cafes," she says.
"But when Lola was born, she started acting differently. I guess that I was totally absorbed in my new baby and maybe not as much fun as I used to be."
Rings said that over time the friends drifted apart, and eventually lost contact. She felt unsupported by her friend and felt changed by motherhood.
Five years later, however, when they bumped into each other at a mutual friend's birthday party, Rings says she was genuinely happy to see her.
"We talked for a while catching up, and it was hard to remember why we had drifted apart. I thought that I didn't need friends like her, because she wasn't there when I needed her, but really, I did need her, to remind me who I was before I had kids."
"We are catching up for lunch next week."