Uy alam ko yan! A few of us sa group namin experienced the same thing especially towards the end ng pregnancy, super frustrating talaga pag gising ka ng umaga at masakit ang fingers mo kahit parang wala kang ginawa hehe. It's usually from the hormonal changes and water retention na nangyayari sa third trimester kaya mas nag-swell ang joints at ligaments, pero honestly just to be safe, best kung i-check mo with your OB para malaman kung ano talaga ang cause, kasi may cases din na it's something else like carpal tunnel. In the meantime, a few of my mum friends swear by doing gentle hand stretches when you wake up, soaking in warm water, at wearing a loose wrist brace while you sleep, it helped them manage the pain until delivery.