SECOND TRIMESTER
Assuming a 40-menstrual-week pregnancy, the second trimester is assumed to
extend from 13–26 weeks.
Normal symptoms are an improved feeling of general well-being.
Round ligament pain is common.
Braxton-Hicks contractions are painless, low-intensity, long-duration
contractions that can be palpated as early as 14 weeks.
Quickening (maternal awareness of fetal movement) is detected at 18–20
weeks by primigravidas and 16–20 weeks by multigravidas.
Average weight gain is 1 pound per week after 20 weeks.
Complications include incompetent cervix (painless cervical dilation leading
to delivery of a nonviable fetus), premature membrane rupture, and premature
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