Short answers, pulled from the story.
Implantation, the moment the future fetus attaches to the uterine wall, typically occurs about eight to nine days after fertilization. This critical event marks the true biological start of pregnancy, yet it happens silently, often before a woman even knows she is pregnant.
The first trimester ends at week twelve, marking the transition from embryo to fetus. During this time, the womb grows to the size of a lemon by eight weeks, and many symptoms such as nausea and tender breasts appear.
Childbirth on average occurs at a gestational age of two hundred eighty days, or forty weeks, which is the standard estimation for individual pregnancies. However, actual childbirth has only a certain probability of occurring within the limits of the estimated due date, with a standard deviation of fourteen days when gestational age is estimated by first trimester ultrasound.
The Institute of Medicine recommends an overall pregnancy weight gain for those of normal weight, defined as a body mass index of 18.5 to 24.9, of 11.3 to 15.9 kilograms, or 25 to 35 pounds, having a singleton pregnancy. Women who are underweight should gain between 12.7 and 18 kilograms, while those who are overweight are advised to gain between 6.8 and 11.3 kilograms.
Thromboembolic disorders, with an increased risk due to hypercoagulability in pregnancy, are the leading cause of death in pregnant women in the United States. Pulmonary embolism, a blood clot that forms in the legs and migrates to the lungs, is a severe risk.
Babies born between 39 and 41 weeks gestation have better outcomes than babies born either before or after this range. This special time period is called full term, and whenever possible, waiting for labour to begin on its own in this time period is best for the health of the mother and baby.