[5] Signs and symptoms of early pregnancy may include missed periods, tender breasts, morning sickness (nausea and vomiting), hunger, implantation bleeding, and frequent urination.

[9] Complications of pregnancy may include disorders of high blood pressure, gestational diabetes, iron-deficiency anemia, and severe nausea and vomiting.

Preterm and postterm are defined above, whereas premature and postmature have historical meaning and relate more to the infant's size and state of development rather than to the stage of pregnancy.

[29] The usual signs and symptoms of pregnancy do not significantly interfere with activities of daily living or pose a health-threat to the mother or baby.

The American Congress of Obstetricians and Gynecologists recommends the following methods to calculate gestational age:[35] Pregnancy is divided into three trimesters, each lasting for approximately three months.

The placenta connects the developing embryo to the uterine wall to allow nutrient uptake, waste elimination, and gas exchange via the mother's blood supply.

[81] A quantitative blood test can determine approximately the date the embryo was fertilized because hCG levels double every 36 to 72 hours before 8 weeks' gestation.

[60][79] A single test of progesterone levels can also help determine how likely a fetus will survive in those with a threatened miscarriage (bleeding in early pregnancy), but only if the ultrasound result was inconclusive.

[83] The resultant estimated gestational age and due date of the fetus are slightly more accurate than methods based on last menstrual period.

[93] A basic prenatal visit consists of measurement of blood pressure, fundal height, weight and fetal heart rate, checking for symptoms of labor, and guidance for what to expect next.

[95] Further studies are needed to access the effect of dietary advice to prevent gestational diabetes, although low quality evidence suggests some benefit.

[96] Adequate periconceptional (time before and right after conception) folic acid (also called folate or Vitamin B9) intake has been shown to decrease the risk of fetal neural tube defects, such as spina bifida.

[103] Being or becoming overweight in pregnancy increases the risk of complications for mother and fetus, including cesarean section, gestational hypertension, pre-eclampsia, macrosomia and shoulder dystocia.

[124][125][126][127] Sex during pregnancy is a low-risk behavior except when the healthcare provider advises that sexual intercourse be avoided for particular medical reasons.

Studies show that performing light moderate intensity and strength exercises while pregnant does not harm the mother’s cardiovascular system and may limit excessive weight gain.

[132][additional citation(s) needed] The American College of Sports and Medicine recommends pregnant women should participate in at least 150 minutes/week of moderate exercise.

The Clinical Practice Obstetrics Committee of Canada recommends that "All women without contraindications should be encouraged to participate in aerobic and strength-conditioning exercises as part of a healthy lifestyle during their pregnancy".

[139] Taking part in this style of exercise, similarly to moderate intensity continuous training, has also been shown to improve glycemic response and insulin sensitivity.

[140] There are specific concerns to be avoided with exercise during pregnancy such as overheating, fall-risk, and remaining in a supine position for an extended period of time.

[141] It has been suggested that shift work and exposure to bright light at night should be avoided at least during the last trimester of pregnancy to decrease the risk of psychological and behavioral problems in the newborn.

[149] To prepare for the birth of the baby, health care providers recommend that parents attend antenatal classes during the third trimester of pregnancy.

Schemes and funding to support education and the means to prevent pregnancies when they are not intended have been instrumental and are part of the third of the Sustainable Development Goals (SDGs) advanced by the United Nations.

[169] Projectional radiography, CT scan and nuclear medicine imaging result in some degree of ionizing radiation exposure, but in most cases the absorbed doses are not associated with harm to the baby.

Asia, Japan and the United States are all seeing average age at first birth on the rise, and increasingly the process is spreading to countries in the developing world like China, Turkey and Iran.

Three studies conducted between 2015 and 2018 indicate a large fraction (~80%) of women without a high school diploma or local equivalent in the US are unmarried at the time of their first birth.

In 2014, the American state of Tennessee passed a law which allows prosecutors to charge a woman with criminal assault if she uses illegal drugs during her pregnancy and her fetus or newborn is harmed as a result.

[188] Transgender people have experienced significant advances in societal acceptance in recent years leaving many health professionals unprepared to provide quality care.

[189] However, transgender people may be subjected to discrimination, which can include a variety of negative social, emotional, and medical experiences, as pregnancy is regarded as an exclusively female activity.

According to a study by the American College of Obstetricians and Gynecologists, there is a lack of awareness, services, and medical assistance available to pregnant trans men.

Due to the important role of the Mother of God in Christianity, the Western visual arts have a long tradition of depictions of pregnancy, especially in the biblical scene of the Visitation, and devotional images called a Madonna del Parto.