<unk> , also known as adolescent<unk> , is<unk>  in a female under the age of 20, according to the WHO.<unk>  can occur with sexual intercourse after the start of ovulation, which can be before the first menstrual period (menarche) but usually occurs after the onset of periods. In well-nourished girls, the first period usually takes place around the age of 12 or 13. Pregnant<unk> rs face many of the same<unk>  related issues as other women. There are additional concerns for those under the age of 15 as they are less likely to be physically developed to sustain a healthy<unk>  or to give birth. For girls aged 15–19, risks are associated more with socioeconomic factors than with the biological effects of age. Risks of low birth weight, premature labor, anemia, and pre-eclampsia are connected to biological age, as they are observed in teen births even after controlling for other risk factors, such as access to prenatal care.<unk> es are associated with social issues, including lower educational levels and poverty.<unk>  in developed countries is usually outside of marriage and is often associated with a social stigma.<unk>  in developing countries often occurs within marriage and half are planned. However, in these societies, early<unk>  may combine with malnutrition and poor health care to cause medical problems. When used in combination, educational interventions and access to birth control can reduce unintended<unk> es. In 2015, about 47 females per 1,000 had children well under the age of 20. Rates are higher in Africa and lower in Asia. In the developing world about 2.5 million females under the age of 16 and 16 million females 15 to 19 years old have children each year. Another 3.9 million have abortions. It is more common in rural than urban areas. Worldwide, complications related to<unk>  are the most common cause of death among females 15 to 19 years old.
Teenage pregnancy
Male lactation
High-risk pregnancy
Drugs in pregnancy
Postterm pregnancy
Male pregnancy
Pre-existing disease in pregnancy
Abortion in South Korea