How does early morning sickness?
First nausea, vomiting and weakness, a woman can feel at 4-5 weeks of pregnancy. Unpleasant symptoms associated with the restructuring of the female body in which are formed all the necessary conditions for the healthy development of the fetus. One of the most significant causes of toxicity – the underdevelopment of the placenta in early pregnancy.
The placenta protects the fetus from the effects of the environment and is a barrier that prevents the metabolic products of the future child to get into the bloodstream women. In the first months of pregnancy, the placenta is just beginning to emerge, resulting in metabolic products secreted by the fetus, causing the expectant mother strong intoxication. The final formation of the placenta occurs in 14-16 week of pregnancy. By that time, gradually disappear and the symptoms of toxemia. Many pregnant women, the nausea disappears by 12 weeks of pregnancy.
Duration of toxicity due to the changing hormonal background of women. Implantation of the ovum in the uterus is accompanied by increased production of HCG (human chorionic gonadotropin) and progesterone. Rising levels of hormones also causes discomfort, but by the 10 week of pregnancy hormonal stabiliziruemost.
The risk of late toxicity
In addition to early toxicity, there is the so-called "late toxemia", which is often called preeclampsia. Unlike morning sickness the first trimester, preeclampsia is a serious health risk to mother and unborn child. The symptoms of late toxicosis appear in the third trimester of pregnancy and are accompanied by severe edema, increased levels of protein in the urine and changes in blood pressure. Morning sickness third trimester requires medical treatment and enhanced medical supervision. Signs of preeclampsia can disappear as a result of treatment at the end of the third trimester, but in some cases they can persist up to the birth.