Stretching abdominal muscles With the growth of the uterus and development of the baby, the belly can start to feel firmer, even this early on. Hardening is mostly due to excessive stretching of abdominal muscles.
Depending on your stage of pregnancy, your body type, and even the time of day, sometimes your belly will feel soft and other times it will feel tight and hard. The reality is, there's no normal to compare yourself with. Pregnant bellies come in all shapes, sizes, and firmness.