As an expecting mom, you may be surprised by how dramatically your body changes during your nine months. Pregnancy is different for every woman, but here’s a rundown of what to anticipate each trimester. Be sure to tell your OB-GYN or midwife about any changes that worry you if for no other reason than to be reassured that everything is okay.

FIRST TRIMESTER

You may not be showing yet but your body is undergoing a tremendous transformation. One of the most common signs of pregnancy in the early months is fatigue, says Kara Nakisbendi, MD, a gynecologist and co-author of The Pregnancy Countdown Book. “It’s a fatigue like no other tiredness you’ve had before,” she explains. “It makes it hard to get things done and you want to sleep all the time.” The cause is high levels of the hormone progesterone, which will lessen somewhat during the second trimester.

Morning sickness is another well-known side effect. More than half of all expecting moms can expect it—and not just in the a.m. “It doesn’t just happen in the morning. It can be worse as the day goes on,” Nakisbendi notes. Most preggers complain of sickness in the form of nausea or vomiting, and ironically, the best way to cope is by eating, particularly protein-rich foods. Remedies like ginger tea may also help.

One surprising symptom that many women experience early on in pregnancy is cramping, similar to menstrual cramps. Nakisbendi says that is due to implantation, when the embryo attaches to the wall of your uterus. It doesn’t mean that anything is wrong, but if cramping is severe tell your OB-GYN or midwife.

In addition to these common changes, you will likely notice breast tenderness and swelling, aversions to certain foods, gassiness, and a more frequent need to urinate, among other physical signs.

SECOND TRIMESTER

You can truly look forward to this trimester because the fatigue and nausea from the first trimester start to subside. But these developments make some women feel as if they’re not pregnant at all. “You’re in a limbo state,” says Nakisbendi. “You’re not quite showing. You don’t feel the baby moving. You’re feeling more like yourself. Most women panic a little but everything is fine.”

Another second-trimester delight that some women report is a boost in libido. It’s due to increased blood flow to the genital area. You may not only find yourself eyeing your partner more often, but your “experience of sex might be enhanced,” says Nakisbendi.

Sometime between weeks 22 and 24 first-time mothers will feel their baby move. Those early kicks may feel like bubbles, flutters, or taps—you may even mistake it for gas initially. But once your baby’s movements are strong enough to feel every day, they will be unmistakable.

The second trimester is not all joy, however. Many women get low back pain, headaches, and what’s known as round ligament pain caused by stress on the ligaments that support your uterus. Additional changes may include mild dizziness, growing appetite, constipation, and vaginal discharge.

THIRD TRIMESTER

During the homestretch you’ll be brimming with anticipation of the Big Day. But you’ll have to endure some more aches and pains, particularly in your lower back and groin, while you wait. Some preggers have heartburn. Others experience breathlessness due to hormonal changes and pressure from their growing uterus on their lungs, says Nakisbendi.

Additional changes may include leg cramps and ankle swelling, hemorrhoids, and difficulty sleeping. Don’t be surprised if you notice yourself dropping objects or knocking into things more often—increased clumsiness is common.

In the last several weeks, many preggers start to feel Braxton-Hicks contractions, the early contractions that begin to prepare your body for delivery. They might feel like a tightening of the uterus or cramps but they won’t be painful, notes Nakisbendi. These practice contractions are not necessarily a sign of impending delivery so don’t go to the hospital unless the contractions become regular, more frequent, stronger and longer. That’s the clearest indication that your pregnancy is drawing to a close and you’ll be meeting your baby soon.