Watching one’s beloved go through pregnancy can be a bizarre and bewildering experience. It is also one that I assumed might be easy for me because we are the same sex.

From the day we met, almost nine years ago, Bella was adamant that she wanted a child – and that she wanted to carry it. She loved the idea of pregnancy with the same vehemence with which I hated it. I wasn’t convinced about having children. Finally, though, after seven years together, when I was 33, I felt ready. We began searching for a sperm donor.

Although our journey towards a child has thus far been relatively short in comparison to that of many couples (heterosexual or otherwise), it has not been easy. First, there were the difficult conversations with certain family members, next the “matchmaking” websites, followed by awkward phone interviews with prospective donors, and then several unsexy artificial inseminations. We were disappointed when not just our first but also our second donor moved abroad. Luckily, we found a generous-spirited, rational man whom we liked and trusted very much to be our third and final donor. Within five months, Bella was pregnant.

Sadly, however, she miscarried at 10 weeks, last June. It was a traumatic experience that has marked her deeply, the true extent of which neither of us could have predicted. Yet we were keen to try again, and three months later she fell pregnant for the second time.

This time things were different – not only did the baby “stick”, but for Bella the first trimester was full of extreme sickness, lethargy and anxiety. The other major difference was that I began to experience all sorts of unexpected emotions: fear, confusion and a sense of being completely set apart from my wife and the baby growing inside her. I was filled with overwhelming self-doubt and a strong desire to run away from everything that spelled out parent.

So much for my lofty ideas about the myriad ways in which I might be more attuned to my partner during the pregnancy, and more invested in our baby, than any man could be.

The reality was far more humbling. I floundered – I totally freaked out. I racked my brains to find the reason for this frightening wobble. Was it an environmental issue, perhaps? Friends spoke earnestly about how this was not a good world into which to bring a child and, in principle (if not in my heart), I agreed. However, I knew that this wasn’t an ethical or political crisis, but a far more personal one. I went back and scoured my emotional horizon a second time, zooming in on my relationship. Sure enough, as with most long-term relationships, there were cracks – issues between us that were manageable now, but which I worried might be exacerbated and become unbearable when faced with the pressures of parenthood.

But still, this wasn’t enough to explain my fear. Truth was, beyond the obvious, there wasn’t a good reason. To put it another way, sometimes the enormity of a situation is itself reason enough to feel scared. I was going to become a parent, and that was a big enough reason for anyone to have a temporary wobble.

“It’s not my pregnancy, but it is our baby,” I reminded myself. Yet still I felt unsure; all my internalised prejudice kept cropping up. If I was to be a mother, why wasn’t I pregnant? Maybe I wasn’t a “real” mother at all. But then what – or who – was I going to be? And what role could – or should – I play? And what should I be called? Most of my friends and acquaintances didn’t question the idea of me as Mother, although a few had (half-joking) suggested Dad, which gave me a strong urge to punch them. Surely, if Bella was Mama (as she would like), I could not be Mummy (as she suggested)?

“Lucy is as much this baby’s mother as I am,” she answered whenever questioned on this topic.

I was relieved she felt this way, but I still felt unsure. It wasn’t that I was trying to demote myself, nor to divest myself of responsibility. I was just searching for a name and an identity that suited me. Rather than adhering to titles and ideas imbued with historic ideas and unhelpful binaries (not to mention other people’s fear-based notions of what constitutes a proper parent), I wanted to embrace the joy of being “other” – to claim it as a positive instead of being relegated to the linguistic cul-de-sac of the negative prefix: non-biological mother, non‑genetically related parent or variations on that theme. By the start of the second trimester, parenthood had somehow become all about identity and was about as far away as possible from the unconditional love I wanted to give our child.

Truth is, I am just a parent: anything beyond that our child gets to decide. Having now spoken to fathers and other non-biological mothers about how they felt, I understand that there is neither a specifically male way to react to pregnancy by proxy, nor a specifically female one. Yet it is not uncommon for the non-carrying partner (regardless of gender) to experience, as I did, feelings of fear, uncertainty, estrangement and even resentment during early pregnancy. Clearly, I was wrong in thinking that being the same sex as Bella might give me an empathetic edge (over men) when it came to sharing in the pleasure and pain of her pregnancy.

Perhaps some of my preconceptions of how I ought to feel (as a woman) were no less obtuse, and no less based on unhelpful stereotypes than the infuriating notion that all non-carrying female parents must be some kind of father figure. And hadn’t I also been arrogant to assume I could be immune to the possibility of feeling ostracised from in-utero bonding just because I am a woman? In the end, it’s not my body that is growing a tiny human, so there is no reason why I should feel more connected to the baby than any male partner might at this stage.

Suffice to say, approaching the third trimester, I no longer try to predict the future. Nor do I attempt to guess what I or Bella will feel, how things will go between us as a couple or how things will turn out for us as a family. Uncertainty has never been more central in my life. I don’t know what kind of parent I will be – which bits of the job I will adore and which bits I will struggle with – just as I don’t know who exactly our child will be. It’s easier this way. When I find myself staring at Bella’s ever-increasing bump, I just hope that I will be good enough, without worrying too much about labels – about non-bios and others and whether I should be called Mum or Lulu or just “hey, you”. I don’t even care so much now if people call me Dad. But don’t try it, just in case …