I found this advice
Strategies for lifting and bending
You are more prone to back strain during pregnancy and after delivery, because the pregnancy hormones have softened your ligaments and joints.
To reach or lift low objects, spread your feet apart with one foot ahead of the other and bend your knees.
Bring the object close to you as you straighten your knees and lift. This allows you to use your thigh muscles for lifting rather than straining your back muscles.
When moving an object, push it instead of pulling it. Use your legs, not your back and arms.
Never bend at the waist with your knees straight, even if it is only a slight bend. Instead, alter your position so that you are sitting, squatting, kneeling or bending at the knees while leaning forward at the hips.
When getting in and out of bed or a car, turn your hips, pelvis and back in the same direction while maintaining a straight back. When getting out of bed, first roll to your side and then use your arms to push from the bed.
here: https://www.babies.sutterhealth.org/during/preg_posture.html#Strategies for lifting and bending - it doesn't hurt the baby, it's more to do with you hurting your back. I do it all the time though but am finding it trickier now. Squatting doesn't help as I get stuck! I might have to invest in one of those grabber devices for the elderly...