The time from conception until birth; the average pregnancy is 280 days. Every organ and tissue of the body of the mother is affected by pregnancy. The time when a woman is most likely to become pregnant is the period between the sixth and eleventh days after the first day of menstruation.
Signs of Pregnancy
The breasts begin to enlarge as early as the second month, and with a first baby, even, sometimes, as early as the second or third week. Among the most definite signs of pregnancy are cessation of menstruation, morning nausea, and vomiting which begins usually during the second month and rarely lasts beyond the fourth month. Another symptom is increased emotionalism, with peevishness, fretfulness and irritability. Cravings for strange foods may appear. Fluttering (called “quickening”) is experienced between the sixteenth and eighteenth week. The usual changes in the shape and size of the body are well known. X-ray will show the presence of the child and, later, its position. The doctor can hear the heartbeat of the child between the eighteenth and twentieth weeks and sometimes even earlier. Laboratory tests like the Aschheim-Zondek test, made on rabbits and on frogs, are accurate determinations of the presence of pregnancy.