Why do we calculate the length of a pregnancy from the first day of a women’s last period?
In: 3216
When a woman becomes pregnant, the first day of her last menstrual period (LMP) is used as a starting point to calculate the length of her pregnancy. This is because the actual date of conception can be difficult to pinpoint, but the first day of the last period is a reliable and consistent marker to use. This information is used to monitor fetal development, track milestones, and plan for labour and delivery.
During a menstrual cycle, the uterus prepares for a potential pregnancy by building up its lining. If conception does not occur, the lining sheds and a woman gets her period. However, if an egg is fertilised by sperm during this time, it will implant in the uterus and start to grow into a fetus. This is a good [podcast](https://open.spotify.com/episode/4mgZ4etwET7slFQuoyrSTv) from the BBC about it
Latest Answers