Found this very simple to understand illustration about posture in pregnancy from Farley Chiro. This is why I keep stressing for good balance and posture starting early in pregnancy.. or better, start now! Remember, 3 important principles for an easier birth (by spinningbabies.com): Balance, Gravity & Movement.
Invest in some money to see a chiropractor during pregnancy to align your body, or to learn general good tips about posture. InsyaAllah, it will be very worth it!