Difficult labor (dystocia) Difficult labor, also known as dystocia or obstructed labor, occurs when the child cannot easily pass through the birth canal. This can result in fetal distress or physical trauma to the child, especially broken clavicles and damage to the brachial plexus nerves. It can also deprive the child of oxygen as the umbilical cord is pinched, potentially causing brain damage or death. Difficult labor may occur because the baby is abnormally large (macrosomia), because the mother’s pelvis or birth canal is small or deformed, or because the baby is in an abnormal presentation for the birth (such as breech or transverse presentation). External causes Fetal malformations and<unk> es may occur as a result of exposure to environmental toxins such as mercury or lead. Many medications can also affect the development of the fetus, as can alcohol, tobacco, and illicit drugs. See Environmental toxins and fetal development. See Drugs in pregnancy. Genetic mutations Genetic mutations can cause a wide variety of fetal malformations, ranging from relatively mild cleft lips to severe and even fatal deformities. Infection Maternal infection may be transmitted to the fetus; this is called a vertically transmitted infection. The fetus has a weak immune system, so infections that are relatively minor in adults can be very serious in a developing fetus. In addition, some studies suggest that maternal infections increase the risk of neurodevelopmental disorders, including schizophrenia, in the child. Intrauterine hypoxia Intrauterine hypoxia, or oxygen deprivation in the womb, can cause serious brain damage in the fetus. It most commonly occurs because of damage to or malformation of the umbilical cord or placenta. Intrauterine hypoxia can cause brain damage, including cerebral palsy and other neurological and psychiatric disorders. Maternal health issues Certain maternal health issues can cause<unk> es. Gestational diabetes can cause premature birth, macrosomia, or stillbirth. Pregnancy complications Complications such as placenta previa, placental abruption, Placenta accreta, Retained placenta, Placental insufficiency, Placental infarcts, anemia, and preeclampsia can limit the supply of oxygen and nutrients to the fetus, increasing the risk of birth defects. Severe cases may be fatal to the fetus.
Birth injury
Birth trauma 
Birth trauma
Birth defect
Stillbirth
Childbirth
Water birth
Birch