She has one of the most recognisable set of pipes in the world, but Adele was convinced her voice changed when she was pregnant. And science has now proved her right.
A new study has discovered that new mums’ voices get lower after having their first baby, which is exactly what Adele experienced. “In pregnancy, my voice got a lot lower, which is why Skyfall (her James Bond theme song) is so low. I couldn’t get up there for (the high notes in) Skyfall.”
Hello, mum voice
The University of Sussex study found that the pitch of a new mums’ voice temporarily drops after their first bub. Researchers studied women’s voices over a decade, five years before and five years after childbirth. What they discovered is that a new mum’s voice gets lower and becomes more monotonous after pregnancy. A year later, a mum’s voice goes back to normal.
“Our results show that, despite some singers noticing that their voices get lower while pregnant, the big drop actually happens after they give birth.” explained Dr Kasia Pisanski. “We analysed voice recordings of natural, free speech during interviews between the mothers and other adults rather than direct speech to their babies, as we know that parents often artificially raise the pitch of their voice when talking to newborns.”
What’s the cause of mum voice?
It’s possible that mums are simply tired, and that’s causing a change in voice pitch, but there are also a couple of other theories.
“One possible explanation is that this is caused by hormone changes after childbirth,” said Dr Pisanski. “Previous research has shown that women’s voices can change with fertility, with pitch increasing around the time of ovulation each month, and decreasing following menopause. We know that after pregnancy, there’s a sharp drop in the levels of key sex hormones and that this could influence vocal fold dynamics and vocal control.”
An even more fascinating theory is that mums are changing their voices to fit with their new role. “Research has already shown that people with low-pitched voices are typically judged to be more competent, mature, and dominant, so it could be that women are modulating their own voices to sound more authoritative, faced with the new challenges of parenting.”
The researchers are now going to study whether postpartum voice changes influence what people think of new mums. In the meantime, take a look at these other five freaky pregnancy conditions you’ve probably never heard of.