I am an anatomist. I know the structure of the human body pretty well, and I know that, on the whole, we're pretty well designed to do what could be considered to be normal human functions. There are certainly some flaws. Cartilage that could repair itself would be a brilliant addition to joints and save us from osteoarthritis. Better connections between the coronary arteries supplying the heart could perhaps help to avert heart attacks, but when they did happen, heart muscle that could regenerate itself would be a bonus. When it comes to the female body – well, slightly wider hips would be just brilliant when it comes to squeezing a baby out through the birth canal. Or indeed, a baby with a smaller head would do just as well. Unfortunately, us humans have evolved to have ridiculously large heads with big brains inside them, and even though a newborn baby's brain is just 30% of adult size, it's big enough. Having had one baby already, the "normal" way, I can vouch for that.

When I was pregnant with my first baby, my husband came along to an antenatal class with me. The midwife pushed a baby doll through a plastic pelvis and said: "The birth canal is about 10cm across, and the baby's head is 10cm, too. It's a perfect fit. Isn't nature wonderful?" I was massively proud of my husband when he piped up and said: "I think nature might be more wonderful if the baby's head was 8cm across." Absolutely. Point well made.

Human birth is difficult. There's no point denying it. Most placental mammals seem to give birth as if it were no more onerous than doing a big poo. Chimpanzees, our closest living relatives, do it with ease. In a video of a chimpanzee giving birth in a zoo in Leipzig, the mum crouches down (with lots of interested chimp onlookers around her), bares her teeth, reaches down between her legs, and pulls out an infant. Just like that. The whole thing takes about two minutes. Humans, on the other hand, have babies with big heads that are a tight fit in the pelvis: human childbirth has always been difficult and dangerous. Where other animals tend to seek solitude during labour, women in every society seek help. It's midwifery that's truly the world's oldest profession.

In four weeks' time, I'm due to have my second baby. I'm lucky – my pregnancy has progressed swimmingly so far. I'm in the happy position of being labelled as a "low-risk" mum, and that means I can make some choices. About where to have my baby, for instance.

I'm not scared of hospitals, and I was very happy with the way that the birth of my first baby was handled in a maternity unit. I also know that, however calming the home environment might be, I'll feel even calmer in hospital. Although I hope for a wonderfully uncomplicated birth accompanied only by a midwife and my husband, I'll be reassured by knowing that there are obstetricians and neonatologists close by. For other women, home might seem like an enticing option. But surely the most important thing to consider when making this choice has to be the safety of both mother and baby.

Here's the problem: evidence about the risks has been hard to come by and difficult to interpret. This is partly because the overall risks of maternal and neonatal death are now very small (about five per 100,000 women die in childbirth and four per 1,000 babies), so large numbers of mums are needed to assess relative risks. Maternity provision differs between countries, so looking at risks in other countries, even in Europe and the US, may not be terribly helpful.

Perfect outcome: the birth debate should centre on babies’ and mums’ safety. Photograph: Christopher Furlong/Getty Images

Another problem is the politics of birth. It can be quite hard for mums-to-be to access impartial evidence and advice when it seems there are plenty of people wanting to influence your decision in one way or the other. Evangelical advocates of home birth often talk about the importance of women's choice and empowerment, as well as instilling distrust in obstetricians. For me, being empowered to make a decision requires access to good evidence and the freedom to make up my own mind. And whilst "maternal satisfaction" is often put forward as an important factor to be taken into consideration, I want to know what the relative risks are. And if there's not yet enough evidence to assess that – I want to know that too.

When it comes to the safety of giving birth in different settings in the UK, a mammoth piece of research was published in 2011: the Birthplace in England research programme looked at 65,000 women, with births planned to take place at home, in midwife-led units, and in hospital. In all those births, there were just 250 where babies died or suffered injury (about four per 1,000). The study found that, for first-time mums, the risk of adverse outcome was higher in home births compared with hospitals (9.3 per 1,000 births compared with 5.3 per 1,000), but there was no difference in risk for women who'd had children before.

Not at all surprisingly, there were fewer interventions (like forceps deliveries and caesarean sections) in the non-hospital settings. (This is something which is often put forward as a pro for home births, which I find odd. There are fewer forceps deliveries in home births because you can only do them in hospital. There are fewer –no – epidurals in home births, but that's to be expected, unless you happen to keep an anaesthetist in a cupboard at home for just such eventualities.) The study found that about four in 10 first-time mums who planned a home birth or birth in a midwife-led unit had to be transferred to hospital during labour, whereas about one in 10 women having second or subsequent births were transferred.

So here's some good, robust evidence that can help mums make properly informed decisions. But it's perturbing to look at the different ways in which the same evidence has been presented, and the priority given to various findings. The Royal College of Obstetricians and Gynaecologists (RCOG) issued a statement on the Birthplace study, listing the findings: the relatively higher risk of poor outcomes for the baby in first-time mums giving birth at home; the 45% transfer rate for home-birthing first-time mums and 12% transfer rate for subsequent pregnancies; the lower intervention rates in home births, in that order.

In stark contrast, look up "home birth" on the National Childbirth Trust (NCT) website, and it kicks off with: "Some experts have said that a first labour is particularly suitable for home birth." If you click through a couple of links to a Q&A on the Birthplace study, the findings are laid out in exactly the opposite order to that in the original research paper and the RCOG's statement: women having a home birth are more likely to have a "normal birth" without intervention; home births are safe for women having a second or subsequent baby; lastly: home birth increases the risk to the baby for first-time mums. The main outcome investigated by the study is the last to be mentioned.

I can't help but be reminded of the (extremely hardline) statement from the American College of Obstetricians and Gynaecologists that "choosing to deliver a baby at home… is to show preference for the process of giving birth over the goal of having a healthy baby". That might be way too harsh, but the way the NCT presents the Birthplace study evidence certainly prioritises the birth process over the risk to the baby. While a normal, vaginal birth with minimum intervention is undoubtedly an ideal to hope for, the most important outcome of a birth has to be a healthy baby and mum. We should be celebrating the success of our multidisciplinary teams – including midwives, obstetricians and neonatologists – which means this is the outcome for the vast majority of mums and babies in the UK in the 21st century.

Women should be empowered to make choices, but need evidence to be able to do that, not spin. Having made our choices, we need to bear in mind the unpredictability of birth and our response to it. No one should feel that having an epidural, a forceps delivery or a caesarean section is a failure. When you've given birth, however and wherever you've done it, and you end up holding a healthy baby – that's the best outcome in the world.