9 surprising truths about pregnancy
When you're pregnant, the questions can seem endless and conflicting headlines, health advice and opinions mean the answers aren't always crystal clear. So, courtesy of Linda Geddes, we've rounded up the most surprising – and scientific! – truths about pregnancy and birth. Prepare to be amazed…
1. Your chances of having a boy or girl are not always 50:50
There are some situations in which the odds of having a boy or girl are ever-so-slightly weighted (apparently). Women in high-stress jobs, older mothers and attractive parents(!) are more likely to have daughters. Men who earn lots of money or work in typically 'male' occupations such as engineering, and women with polycystic ovarian syndrome or multiple sclerosis, are more likely to have sons.
2. Babies aren't born blank slates
Newborns already have some concept of whom their mother is (they know her voice and smell) and what a human face should look like, as well as an appreciation of numbers, movement and distance. They also have a natural sense of rhythm.
3. Dads are primed for fatherhood
If you thought mums were the only ones whose hormones go haywire at birth, think again. Levels of testosterone decline in new dads, while levels of the breastfeeding hormone prolactin and the cuddle-chemical oxytocin both rise. All these changes seem to be associated with dad-like behaviour – and the more dads interact with their babies, the more these hormones rise. It’s a cycle of dad-love.
4. Breastfeeding doesn't make your boobs sag
It's actually all the changes that occur during pregnancy that are responsible for creating saggy boobs. Fat gets replaced with glandular tissue, and this can stretch the skin and ligaments in the breasts. Once you stop breastfeeding (or even if you never start) this network of milk-producing glands then self-destructs, leaving gaps that need to be filled with fat.
5. Having an epidural doesn't mean you're more likely to need a C-section
There's no strong evidence that having an epidural to dull labour pains will mean you're more likely to end up on the operating table. Neither are you vastly more likely to need an instrumental delivery (involving forceps or a suction device called a ventouse). Around 20 women would need to have an epidural for just one extra instrumental delivery to take place.
6. Giving a bottle or dummy to a newborn won't 'confuse' it
There is little scientific evidence for the existence of 'nipple confusion' – a phrase beloved of health visitors who try to discourage the early introduction of dummies or bottles by warning that babies will no longer want to drink from the breast.
7. Biodegradable nappies aren't necessarily any greener than standard disposables
Put a biodegradable nappy into landfill and it won't biodegrade because it's largely cut off from the water, oxygen and bacteria needed for decomposition to occur. You need to compost them instead. Reusable nappies washed at a moderate heat and line-dried are greenest of all.
8. Babies CAN see further than 30cm in front of them
Babies can focus on objects at any distance, but because they're not very good at it they often over- or under-shoot. Because the connections between their eyes and brain aren't completely mature, the world also appears quite grainy.
9. 'Dada' isn't the most common first word because they prefer their dads
Sounds like “ba” “da” “ga” and “ma” are some of the easiest to make, so that's where babies tend to start. But “ma” is harder than “da” because you have to relax your soft-palate as well as moving your lips and jaw. “Ma” is also less common than “da” in everyday language, so the fact that babies usually start with “dada” may reflect this. At any rate, early baby babble isn't supposed to be any more than just noise, so mums shouldn't feel hurt if their baby says dada first!
Linda Geddes is the author of Bumpology – The myth-busting pregnancy book for curious parents-to-be. She writes about biology, medicine and technology for publications including New Scientist, and is a mother of two.