There is some diversity of medical opinion about exactly when the second trimester begins and ends. The Office on Women’s Health at the US Department of Health and Human Services defines the second trimester as weeks 13–28, and PregnancyCorner follows their lead. However, the American Pregnancy Association and the UCSF Medical Center at the University of California, San Francisco both consider the second trimester to run from week 14 to week 26. Other experts label the second trimester from weeks 14 to 27, with the third trimester starting exactly at 28 weeks.
Second Trimester Pregnancy Symptoms
As the second trimester begins, many of the most unpleasant pregnancy symptoms will begin to ease or go away. Your nausea should ease, and your energy level will likely increase. Other symptoms may appear, however, and some first-trimester symptoms will continue to plague you. Second trimester pregnancy symptoms tend to include:
You can expect changes to your breasts during this time—they will begin to grow larger, and your nipples and areolae may darken, especially if this is your first pregnancy. Your belly will begin to grow visibly at this point, and you may therefore begin to see stretch marks there and on your breasts, although many women do not get any stretch marks at all. During the second trimester, especially the second half, you may also begin to experience Braxton Hicks contractions.
Another side effect of pregnancy is an increase in blood circulation—which includes blood flow to the mucous membranes. This causes swelling in your nasal passages, which can lead to nasal congestion and possibly even nosebleeds (your partner should be warned that you may also snore because of this). Another possible result of this increased blood circulation is softening of the gums, which may result in minor bleeding when you brush your teeth or floss.
A thin, white, acidic vaginal discharge may begin to appear during the second trimester. This discharge is believed to discourage the growth of yeast and bacteria.
Perhaps the most exciting event to happen during the second trimester is this: sometime between your 16th and 20th week of pregnancy, you may feel your baby begin to move! First timers tend to feel movement closer to 20 weeks. They describe those first sensations as a faint fluttering or tickling or perhaps a bubbling type sensation in their lower belly. One day those tickles are going to become kicks and punches!
By the End of the Second Trimester
The fetus is now covered with a fine hair called lanugo, which will disappear by the end of your pregnancy. If your baby were to be delivered now, there is even the possibility that it could survive with medical assistance (the earliest gestational age at which there is a decent chance of survival is about 24 weeks). Your baby should now be about 14 inches long and weigh about 2 ¼ pounds.
Read more about your week: