New mum Rawinia Dolan reckons she managed okay at work until her 38th week despite some "baby brain moments" during her pregnancy. Photo supplied
A scientific study has proved what most women have always known - that pregnancy can upset your brain as well as your body.
The new study, published in the Medical Journal of Australia in January, has found that women in their last three months of pregnancy averaged significantly lower memory and "executive functioning" than other women.
A study author Associate Professor Linda Byrne of Deakin University said "baby brain" symptoms could include poor concentration and absent-mindedness, with up to 81 per cent of women reporting some effects.
"That seems to confirm a lot of what we hear anecdotally where women say they start forgetting things during pregnancy - they put the car keys in the fridge or miss appointments," she said.
But Dr Nikki Turner of Auckland University's Conectus child and maternal health research group said pregnancy was only one of many things that affected people's mental functioning.
"A lot of things in the environment affect our memory and our cognitive ability, such as having a cold, losing sleep or feeling stressed," she said.
The study analyses 20 previous "baby brain" studies published globally between 1986 and 2014. Although some of the studies did not find that pregnancy had any significant effect, the new study found that effects on the brain were significant when measured across the total of 709 pregnant women and 521 other women who were involved in all 20 studies put together.
The combined study found pregnant women in their third trimester performed well below the average for other women on memory tasks, and slightly below average on "executive functioning" which includes attention, planning, shifting between ideas, generating new responses, problem-solving and abstraction.
However the studies found no significant effect on attention when it was measured separately.
The clinical director of the NZ Maternal Fetal Medicine Network, Dr Emma Parry, said she had memory problems herself when pregnant with her daughters now aged 19 and 15.
"I had problems with words," she said. "I'd be thinking about medical terms. I knew exactly what it was, I just couldn't put my finger on it.
"Once my children started sleeping through, that's when I started to feel I just got my brain back... I don't think it came right till my kids were 4 months old."
However she continued delivering babies until she was 38 weeks pregnant and said the memory problems did not stop her doing a good job.
"I'm a big believer in lists. I used to have lots of lists everywhere," she said.
Turner said the studies were based on averages and could not be used to draw any conclusions about an individual such as Prime Minister Jacinda Ardern, who is expecting her first baby in June.
"For some women there is some effect on aspects of your cognitive functioning. That does not mean it applies to all women, and it's not a huge effect," she said.
"We have a huge amount of really high-functioning women out there who perform extremely well through all stages of pregnancy."
Coping with 'baby brain moments'
New mum Rawinia Dolan says she definitely had more forgetful moments than normal while she was pregnant.
Dolan, an Auckland public relations consultant, gave birth to her first child on January 21.
She and her husband, carpenter Gideon Dolan, met when they were both working in the Cook Islands and have named their daughter Hanalei, meaning "valley of flowers" in Hawaii where the couple went for their honeymoon.
"I worked till 38 weeks, and there were definitely a few moments, like arriving at work and your laptop's at home, and losing your phone," she said.
Although such things can happen to anyone, Dolan felt it happened "more than normal".
"There were definitely 'baby brain' moments, I guess it's just more like the frequency of things," she said.
"I think you have days where it might feel like it's a bit more full-on than normal. In general, I think I was still managing okay, but near the end I think it was touch and go."
However Dolan said she was lucky to have a supportive partner at home and an all-female team at work who provided "emotional support".
"You just have to make sure that when you get home you can rest and look after yourself," she said.
She believes the Prime Minister will handle it.
"If you're someone that is used to being busy and full-on, you will be able to handle it. I think people like her will be able to manage it pretty well," she said. "She can just delegate what she can."
How to cope
1. Lists: Dr Emma Parry had lists "everywhere" to make sure she didn't forget things.
2. Sleep: Dr Parry and Dr Nikki Turner advise plenty of rest and sleep.
3. Emotional support: Dr Parry advises "support from partners and other friends" to keep your mind steady.
4. Diet: Dr Parry advises using supplements if necessary to maintain levels of folic acid, iodine, choline, calcium and omega-3 fatty acids found in oily fish.