2017年1月31日 · Labor is the process by which the fetus and the placenta leave the uterus. Delivery can occur in two ways, vaginally (through the birth canal) or by a cesarean (surgical) delivery. NICHD provides detailed information about these topics on its Labor and Delivery page.

2017年4月25日 · The first stage of labor happens in two phases: early labor and active labor. Typically, it is the longest stage of the process. During early labor: The opening of the uterus, called the cervix, starts to thin and open wider, or dilate. Contractions get stronger, last 30 to 60 seconds, and come every 5 to 20 minutes.

2017年2月13日 · For most women, labor begins sometime between week 37 and week 42 of pregnancy. Labor that occurs before 37 weeks of pregnancy is considered premature, or preterm.1 Just as pregnancy is different for every woman, the start of labor, the signs of labor, and the length of time it takes to go through labor vary from woman to woman and even from …

2017年8月7日 · If not, and if the pregnancy is at or near term, the provider will likely induce labor. If a pregnant woman's water breaks before 34 weeks of pregnancy, the woman will be monitored in the hospital. Infection can become a major concern if the woman's water breaks early and labor does not begin on its own. 7,8; Perinatal asphyxia.

2014年3月5日 · Infants born in the 37th and 38th weeks of pregnancy—previously called term but now referred to as “early term”—face more health risks than do those born at 39 or 40 weeks. 2. Deliveries before 37 weeks of pregnancy are considered “preterm” or premature: Labor that begins before 37 weeks of pregnancy is preterm or premature labor.

2017年9月1日 · "Labor" and "delivery" describe the process of childbirth. Contractions of the uterus and changes in the cervix (the opening of the uterus) prepare a woman's body to give birth. Then the baby is born, and the placenta follows. NICHD studies many aspects of labor and delivery: their basic biology, childbirth practices, and management of related problems. A …

2018年5月16日 · Women who have delivered preterm before, or who have experienced preterm labor before, are considered to be at high risk for preterm labor and birth. 1 Being pregnant with twins, triplets, or more (called "multiple gestations") or the use of assisted reproductive technology is associated with a higher risk of preterm labor and birth.

2020年12月30日 · Preterm labor is labor that begins before 37 weeks of pregnancy. Any infant born before 37 weeks is at an increased risk for health problems, in most cases because organs such as the lungs and brain finish their development in the final weeks before a full-term delivery (39 to 40 weeks).

2017年1月31日 · Pregnancy is a period of up to 41 weeks in which a fetus develops inside a woman’s womb. NICHD conducts and supports research and training to help promote healthy pregnancies, with a focus on the important events that occur before, during, and after pregnancy.

2017年2月6日 · Several factors can make a pregnancy high risk, including existing health conditions, the mother’s age, lifestyle, and health issues that happen before or during pregnancy.This page provides some possible factors that could create a high-risk pregnancy situation. This list is not meant to be all-inclusive, and each pregnancy is different, so the …