Kudos for doing your pregnancy homework -- your abdominal pain is most likely round ligament stretching. Here's why this happens: Your round ligaments are basically two bands of tissue that support your uterus; they get pulled and stretched to accommodate your growing uterus and baby. The pain usually starts between 18 and 24 weeks (around or soon after you start showing) and typically occurs on one side of your belly, though it can strike both.
The pain is usually sharp and lasts for just a few seconds. It can be triggered by any movement that causes these ligaments to stretch, like coughing, sneezing, laughing, or getting up suddenly. It can be worrisome when you first feel the pain, but you should know that it's totally normal and usually nothing to be concerned about. Although you can't prevent round ligament stretching, there are some things you can do to alleviate your discomfort:
• Change the way you move: Sit down and get up more slowly and try not to turn sharply at the waist.
• When you feel the pain, bending forward slightly can help soothe it.
• Round ligament pain can be exacerbated by exercise, so you may want to skip or take it easy at the gym until you feel better.
• Apply an ice pack for 20 minutes.
• Take Tylenol (with your doctor's okay) to help relieve the pain.
However, you should let your doctor know right away if the pain lasts longer than a few seconds, or is accompanied by other symptoms like bleeding, cramping, lower-back pain, fever, chills, changes in vaginal discharge, nausea or vomiting, or pain during urination. These could be signs of more serious, but rare, conditions like preterm labor or ovarian cysts.