Milestones You Should Have When You’re Pregnant The Positive Pregnancy Test. First Time You Have Morning Sickness. First Prenatal Appointment. Telling Someone You’re Pregnant. End of the First Trimester. Buying the First Thing for Baby. Hearing Baby’s Heart Beat. Wearing Maternity Clothes. Click to see full answer. Also know, what are the milestones in each trimester of pregnancy?Throughout your pregnancy, your child will develop from a simple egg to a baby. There are many milestones your child will meet, starting at the time of fertilization to delivery, including developing a heartbeat during the first trimester and growing a full head of hair in the third trimester.Beside above, what’s the most important time in pregnancy? The first trimester is the most critical time in your pregnancy. Although the fetus at the end of three months is only about 4 inches long and weighs less than 1 ounce, all of its functions have begun to form — major organs and nervous system, heartbeat, arms, fingers, legs, toes, hair, and buds for future teeth. In respect to this, what are the milestone weeks in pregnancy? Some milestones you may hit include: 4 weeks: A ball of cells called a blastocyst has officially become an embryo, roughly the size of a poppy seed. This is when organ development begins, lasting approximately six weeks. 5 weeks: The baby’s heart begins to beat, generally at about twice the rate of an adult heart.Is 12 weeks pregnant a milestone? Your Life at 12 Weeks Pregnant Be your BFF: Be gentle on yourself. The end of the first trimester is a major milestone, but if you still feel crummy—or on the flipside, if symptoms have faded and you don’t “feel pregnant” anymore—it’s OK to be more nervous than relieved as you enter the second trimester.