Pregnancy, also referred to as gestation, is that the time during which one or more offspring develops inside a lady . A multiple pregnancy involves quite one offspring, like with twins. Pregnancy can occur by sexual activity or assisted reproductive technology. A pregnancy may end during a birth , miscarriage, or abortion. Childbirth typically occurs around 40 weeks from the beginning of the last menstrual period (LMP). this is often just over nine months, where monthly averages 31 days. When measured from fertilization it's about 38 weeks. An embryo is that the developing offspring during the primary eight weeks following fertilization, after which, the term fetus is employed until birth. Symptoms of early pregnancy may include missed periods, tender breasts, nausea and vomiting, hunger, and frequent urination. Pregnancy could also be confirmed with a bioassay . Pregnancy is split into three trimesters, each lasting for about 3 months. the primary trimester includes conception, which is when the sperm fertilizes the egg. The embryo then travels down the Fallopian tube and attaches to the within of the uterus, where it begins to make the embryo and placenta. During the primary trimester, the likelihood of miscarriage (natural death of embryo or fetus) is at its highest. round the middle of the trimester , movement of the fetus could also be felt. At 28 weeks, quite 90% of babies can survive outside of the uterus if given high-quality medical aid . Prenatal care improves pregnancy outcomes. Prenatal care may include taking extra vitamin Bc , avoiding drugs and alcohol, regular exercise, blood tests, and regular physical examinations. Complications of pregnancy may include disorders of high vital sign , gestational diabetes, iron-deficiency anemia, and severe nausea and vomiting among others. within the ideal childbirth labor begins on its own when a lady is "at term". Babies born before 37 weeks are "preterm" and at higher risk of health problems like spastic paralysis . Babies born between weeks 37 and 39 are considered "early term" while those born between weeks 39 and 41 are considered "full term". Babies born between weeks 41 and 42 weeks are considered "late term" while after 42 week they're considered "post term". Delivery before 39 weeks by labor induction or cesarean delivery isn't recommended unless required for other medical reasons.