This article was medically reviewed by Lauren Demosthenes, MD, OB-GYN, senior medical director at Babyscripts. Pregnancy stretch marks happen due to rapid changes like the baby's growth and weight ...

According to Dr. Sudheer Jayaprabhu, an ob-gyn at Christus Health in Texas, most definitions of second trimester have it stretching from week 13 to week 28 of the pregnancy. Prenatal testing ...