It's all about your processing memory, it's like you don't have quite enough RAM. The good news is the brain has been proven to have excellent re-wiring capability, so your faculties will return, I promise!
Interestingly, women's brains GROW by about 25% when pregnant. They do not lose this extra brain-power. (OK, brains don't actually grow, but the neurons inside develop and link and do stuff to give us extra brain-power.) However, research also shows (and I wish I could remember the paper, but how apt that I can't!) that once the baby is born, 50% of the brain (that's 50% of your 125% brain, so just over 60% of a non-mummy brain) is focussed soley on your offspring. So you are working the rest of your life with just over 60% brain-power.
Mothers have better brains, but only for their children!
(FWIW, my memory is now getting stronger and I blame a wonderful childcare centre with fantastic carers so I don't worry about my son much at work - I'm assured this happens to other women once children are at school or grown up, they need less of your brainpower on them at any one time.)
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