Pregnancy by month
If you count pregnancy by months, then it turns out exactly 9 months. In the first two months from the moment of conception, a new organism in the womb of a woman is usually called an embryo, and its size does not exceed 30 mm in length. In the future it is called a fruit.
Now pregnancy by months of an obstetrician is considered rare: it is more correct and more convenient to do it for weeks and trimester. The average duration of gestation is 40 weeks (three trimester for three months in each), although the normal period varies from 37 to 42 weeks.
The sensitivity of the embryo and fetus to negative influences is the higher, the shorter the gestation period. During the embryonic period, the risk of spontaneous abortion is approximately 10 times higher than during the fetal period - from the 9th week before the birth.