EVEN for the most nauseatingly happy couple, the effect of a new baby can be like throwing a grenade under the relationship.
While your relationship will never be the same again, with a bit of luck and a lot of work, it might even be better.
And a new study by the Murdoch Children's Research Institute suggests the key to lasting emotional (and sexual) satisfaction post birth may lie with the fathers.
The Maternal Health Study investigated the health and wellbeing of over 1500 first time mothers, asking them about sexual pleasure and emotional satisfaction in the first year and a half after childbirth. A smaller group were followed up three years later.
What they found was that while sexual satisfaction appeared to improve in the 18 months following childbirth, emotional satisfaction appeared to decline.
But it wasn't as simple as 'happy sex life, sad emotional life.' Keep in mind that the 'improvement' in sexual satisfaction was actually an improvement on how they felt following childbirth. (If you've ever pushed something the size of a grapefruit out of your nethers, then followed it up with six weeks' sleep deprivation, you'll know any improvement sprang from a pretty low base.)
Importantly, the study findings highlighted the extent to which sexual pleasure and emotional satisfaction are linked.
And what made the number one difference to emotional satisfaction? It wasn't new fathers bringing home flowers once a week. It wasn't fathers telling their partners they were still beautiful with a three-month post-natal belly.
It was fathers who shared the domestic drudgery.
Fathers who play an equal role in the endless wiping, soothing, laundering and organising may not be featured in any Lynx ads anytime soon. But the degree to which they shared involvement in household tasks was what made the most difference to the ongoing emotional satisfaction of the new mothers who took part in the study.
However, women whose partners occasionally 'helped out' with housework as opposed to sharing the load were the least emotionally satisfied, and that dissatisfaction increased as time went on.
None of this is news to Dani, mother of three-year-old Arlo.
"Before we had Arlo, my husband and I had what I thought was a good relationship. But looking back, because we were both independent and working, we never had to really negotiate that domestic space," she said.
"Once Arlo came everything changed. In those first few months you're under siege emotionally and physically, and we never got around to having that conversation about who would do what. I guess we just reverted to the roles we'd seen in our own families during childhood.
"As soon as my then-husband went back to work, in addition to caring for a new baby round the clock, I also became the housemaid, cook and cleaner by default.
"Now that we've separated, I can really see how I lost that sense of being in a partnership. It was less like having a partner, and more like having one more person to take care of."
"Partnership and sharing the workload," says Dr Ellie McDonald, one of the study's co-authors, "emerged as an important theme for mothers. Feeling part of a team really made the difference. And nothing makes you feel more part of a team than when partners share the domestic load."
Dani, who eventually separated when Arlo was two, added: "It's funny the things that end up being important. So much of the household tasks seem unimportant or insignificant, but it represents a larger pattern.
"I'll never forget watching my partner kick the full washing basket out of the way instead of helping. I realised he saw 'that stuff' as women's work, and unless I twisted his arm to get some basic help every single time, that would be our life together. It was at that moment that I realised it was over."
ACKNOWLEDGE THE CHANGES
For women, having a baby also represents an enormous identity shift. Emotional satisfaction was strongly related to how much couples could talk about the changes in their relationship.
"Some of the women we spoke to felt grief and a sense of loss at the change in the emotional connection to their partner," Dr McDonald said.
"There's an imbalance in the role change for women, especially if their partner's work and social life doesn't change as much. Whereas many aspects of women's life can change; physically, emotionally, socially, vocationally.
"Often women have worked in paid roles outside the home prior to becoming a mum, which can feel like a role that doesn't get valued in the same way. So if a partner is sharing the mundane tasks, it's about feeling valued."
It may seem obvious, but it's remarkable how easy it is to neglect those important conversations after a full day of parenting. But Dr McDonald said that couples who were able to talk about the changes to their relationship and negotiate challenges together reported a much stronger emotional bond with their partner.
GIVE MOTHERS TIME TO THEMSELVES
The other important finding was that mothers who had regular timeout to do things for themselves were more likely to be more emotionally satisfied in their intimate relationship.
And not 'time when the father takes the baby out so she can do the vacuuming in peace'.
"Women who had time to themselves at least once a week were also more likely to say that they were extremely or very emotionally satisfied, compared to women who had time to themselves once a fortnight or less," the Maternal Health Study found.
"Having a new baby is a time of enormous change for both men and women," said Dr McDonald. "It can be hard for fathers to know what to do to support their partner or show their love. They may find it reassuring to know how much women appreciate the time they put into contributing to household tasks and caring for their baby."
TOP TIPS FOR DADS:
1. Share the day-to-day domestic load
2. Talk about the changes to the relationship (even if it's uncomfortable at first)
3. Help your partner have a significant amount of time to herself each week
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