There's a strong band of connective tissue in your pelvis, supporting your uterus. Known as the round ligament, this band has to stretch as your uterus expands, which can cause some discomfort. The pain is generally felt in the groin or lower abdomen and can be on either side. Although the pain starts in the pelvis, it may travel up to your hips. You may feel a short, sharp stabbing pain or a more prolonged, dull ache.
You will soon adapt and find sitting and lying positions that cause you the least discomfort and which may relieve discomfort. Also, try other common methods of pain relief, too, such as taking a warm bath or resting comfortably with your feet up.
Round ligament pain is common in pregnancy and isn't a cause for concern. See your doctor, however, if you have sharp abdominal or pelvic pains don't resolve quickly or if your pain becomes crampy; if there is any bleeding; if there is a burning sensation when you urinate; or if you're feverish. If you're in any doubt, always seek medical advice.