The universal truth nobody told me about second pregnancies.

When I saw those pink double lines on a pregnancy test eight months ago, I thought I knew what was in store.

I've been here before after all.

A two-to-three-year gap between siblings is pretty common nowadays, and I was joining the club.

Watch: questions about childbirth answered by mums. Post continues below.

I knew this time was going to be different because of the whole 'running after a tiny human thing' — less rest, less time for myself, more carrying around of a wriggly toddler.

But what I wasn't expecting was just how physically different a second pregnancy would feel in my body.

I've lost count of the number of times my physio or my midwife has said to me, "mmmm, yes, that's because it's not your first," and sorry what? Why did no one warn me?

It's not just that your bump gets bigger, quicker (that at least, is pretty common knowledge), it's that any aches and pains you might've felt first time around also arrive much, much sooner.

"Your ligaments are more stretched this time," I was told with a shrug.

First time around, I dealt with some pretty hectic pelvic girdle pain in the final month before birth, teemed with a weird spasm in my hip flexor.

This time around, I've developed both conditions months earlier, and three times as bad.

Apparently this can apply to a whole host of symptoms; nausea, fatigue, varicose veins, haemorrhoids, insomnia….

The pressure is also worse in my pelvis. It feels like my baby is going to drop out at any moment, especially at the end of the day. Completely normal, apparently, for subsequent pregnancies.

"If I had a dollar for every time I heard a second time mum ask me that," laughed my midwife.

"They always think it means they're going to go into labour earlier, but it's just that your abdominal muscles aren't as taut, so everything feels lower and heavier," she added.

Oh joy.

The reality of that means, I can feel the baby kicking my cervix and bladder much sooner and with much more vigour.

"They've got more room to move, it's stretchier this time," I was told.

By early afternoon, I feel a desperate need to be horizontal and take the pressure off.

"I don't remember feeling this debilitated," I keep telling my husband.

Then there's my son. I am dealing with all of these added symptoms and pressures, while also trying to wrangle him. Honestly? It feels hard.

Really bloody hard, and that whole quote about 'pregnancy being as metabolically taxing as an ultramarathon' rings true even more so this time around.

As I've come to terms with the extra aches and pains, I've found myself looking at women like Ballerina Farm's Hannah Neeleman with a mix of awe and horror. If this is what two pregnancies feel like, how on earth did she do eight?

Excuse me, Hannah, I need to know if you and your pelvic floor are….ok??? Image: @ballerinafarm.

According to the World Health Organisation, a woman's risk of complications can increase with the number of pregnancies she has.

The likelihood of developing things like prolapse, urinary incontinence, anaemia, gestational diabetes, hypertension and postpartum haemorrhage all increase.

Several studies have shown that having pregnancies too close together can also increase your risk of certain conditions, with women recommended to wait at least 12 months before getting pregnant again to give their bodies adequate time to recover.

As I head towards the pointy end of this pregnancy, I've been told that a quicker labour and much less time pushing might also be ahead of me. That, at least, for someone who pushed for over two hours with baby one, requiring an episiotomy and ventouse to finally deliver, is something I can hopefully look forward to.

But experiencing pregnancy for a second time has opened my eyes up to a whole new level of strength.

Women truly are incredible. The fact we do all of this with one, two, three children in tow — with a large majority of us also holding down jobs until pretty close to full-term, is simply astounding.

Again and again, I keep having the realisation in this journey that our society truly doesn't give women the grace and care they need while growing life.

We expect them to keep turning up and pretending like they're not in pain. Not struggling. Not going through something insanely hard.

Read: 'I hate pregnancy and saying so got me cancelled.'

Don't even get me started on the way we treat new mothers. As a society, we still have so far to go when it comes to nurturing and holding women through these experiences.

Truly, I shouldn't be surprised I'd never heard about this whole — it'll likely hurt earlier and for longer the second time — thing. We've been conditioned to never explain, never complain (in public).

We've been taught to just be grateful. That someone else is always doing it harder.

But two things can be true.

So if you're struggling with pregnancy, no matter if it's your first, second, third or eighth, please remember that literal scientists have determined that pregnancy is the most energetically expensive activity the human body can maintain for nine months.

Consider yourself an elite athlete, mama.

I sure am glad there's a finish line.

Feature image: Supplied.