Ultrasound has given many lifesaving warnings for who is at risk for placenta previa, and follow-up ultrasound has been helpful in either warning those women who continue to be in peril or in reassuring those whose risk lessens over time.
Round Ligament Pains
During the second trimester, the uterus grows so big that it can no longer sit within the pelvis and it pops up, becoming an abdominal organ. At this time, the second trimester's round ligament pains replace the menstrual-like cramps and growing pains of the first trimester.
The round ligaments are supports which originate on the sides of the uterus, run through the inguinal canals, and insert on the side walls of the vagina and even inner thigh. Since the round ligaments are a pretty lousy support even when the uterus is only the size of a pear, they provide even less support when the uterus gets considerably larger in the second and third trimesters.
The uterus can actually fall from side to side, twanging the round ligaments so that a woman complains of pain on one or both sides where her hip flexes up against her abdomen. This is the inguinal region where the round ligament is crossing. It is a completely harmless pain, but it can really knock a woman for a loop and stop her dead in her tracks. Usually, changing position will relieve this strain on the ligament, lessening the discomfort, but the only final cure is delivery several months later.
To sum up, the second trimester usually gives a pregnant woman a break. And if the big, bad things are ruled out—which they almost always are—this in-between time can give you the opportunity to relax and rejoin the world after the initial challenges of the first 12 weeks and prepare for the biggest step to come. Have a wonderful journey!