Search results
Results From The WOW.Com Content Network
The placenta (pl.: placentas or placentae) is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation.It plays critical roles in facilitating nutrient, gas and waste exchange between the physically separate maternal and fetal circulations, and is an important endocrine organ, producing hormones that regulate both maternal and fetal ...
Some degree of weight gain is expected during pregnancy. The enlarging uterus, growing fetus, placenta, amniotic fluid, normal increase in body fat, and increase in water retention all contribute weight gain during pregnancy. The amount of weight gain can vary from 5 pounds (2.3 kg) to over 100 pounds (45 kg).
In pipefish placentas form following the interaction with the egg and the skin. Despite the placenta forming from pre-existing tissues, in many instances new structures can evolve within these pre-existing tissues. For example, in male seahorses the underbelly skin has become highly modified to form a pouch in which embryos can develop.
Manual placenta removal is the evacuation of the placenta from the uterus by hand. [6] It is usually carried out under anesthesia or more rarely, under sedation and analgesia . A hand is inserted through the vagina and cervix into the uterine cavity and the placenta is detached from the uterine wall and then removed manually.
The embryo, the extra-embryonic membranes, and the placenta are collectively referred to as a conceptus, or the "products of conception". Rapid growth occurs and the embryo's main features begin to take form. This process is called differentiation, which produces the varied cell types (such as blood cells, kidney cells, and nerve cells).
Extravillous trophoblasts grow out from the placenta and penetrate into the decidualized uterus. This process is essential not only for physically attaching the placenta to the mother, but also for altering the vasculature in the uterus. This alteration allows an adequate blood supply to the growing fetus as pregnancy progresses.
The causes of postpartum haemorrhage can be separated into four main categories: Tone, Trauma, Tissue, and Thrombin. Tone represents uterine atony, the failure of the uterus to contract adequately following delivery. Trauma includes lacerations or uterine rupture. Tissue includes conditions that can lead to a retained placenta.
Placenta problems (placenta praevia, placental abruption or placenta accreta) Failed labor induction; Failed instrumental delivery (by forceps or ventouse (Sometimes, a trial of forceps/ventouse delivery is attempted, and if unsuccessful, the baby will need to be delivered by caesarean section.) Large baby weighing > 4,000 grams