Pregnancy is the time during which one or more offspring develops inside a woman's uterus. A multiple pregnancy involves more than one offspring, such as with twins. Pregnancy usually occurs by sexual intercourse, but can also occur through assisted reproductive technology procedures. A pregnancy may end in a live birth, a miscarriage, an induced abortion, or a stillbirth. Childbirth typically occurs around 40 weeks from the start of the last menstrual period, a span known as the gestational age. This is just over nine months. Counting by fertilization age, the length is about 38 weeks. Pregnancy is "the presence of an implanted human embryo or fetus in the uterus"; implantation occurs on average 8–9 days after fertilization. An embryo is the term for the developing offspring during the first seven weeks following implantation, after which the term fetus is used until birth.

Read more in the app

Certain Jobs Linked to Increased Risk of Miscarriage / Pregnancy Loss

Average pregnancy length in the US is shorter than in European countries

Risk or Relief? Scientists Call for More Research on Antidepressants and Pregnancy

Effective and Safe Pregnancy Pain Relief: Acupuncture Shown To Ease Lower Back Pain

Pre-eclampsia and hypertension in pregnancy linked to 19 gene variants

Antidepressant use, infection during pregnancy linked to neurodevelopmental changes in babies, study suggests

Drinking coffee regularly after pregnancy may lower the risk of type 2 diabetes for women who had diabetes during pregnancy

Pregnancy causes dramatic changes in the brain, study confirms

Pregnancy causes dramatic changes in the brain, study confirms

Speeding up treatment for pregnancy-related hypertension

There's a Weird Link Between Teeth And The Evolution of Pregnancy

Drinking Even Low Amounts of Alcohol During Pregnancy Changes Baby’s Brain Structure

Pregnancy Changes the Brain, Possibly Promoting Bonding with a Baby

Challenging guidelines on pregnancy interval following miscarriage or abortion

Drinking during pregnancy changes baby's brain structure

Researchers move closer to better care for life-threatening pregnancy condition

'Organ-on-chip' shows how uterus coaxes embryo to implant in early pregnancy

Adverse pregnancy outcomes in women with inactive inflammatory bowel disease

Periods and pregnancy still taboo in women's football, research finds

New RSV vaccine given in pregnancy protects newborns from illness, Pfizer says