Many difficulties can arise with a pregnancy even after the sperm successfully fertilizes the oocyte. A major problem occurs if the fertilized egg tries to implant before reaching its normal implantation site, the uterus. ...

Bisphenol A (BPA) is an organic compound that was first synthesized by Aleksandr Dianin, a Russian chemist from St. Petersburg, in 1891. The chemical nomenclature of BPA is 2,2-bis (4-hydroxyphenyl) propane. The significance ...

Conjoined twins are twins whose bodies are anatomically joined in utero. The degree to which the twins are attached can range from simple, involving skin and cartilage, to complex, including fusion of the skull(s), brain(s), ...

Fetal surgeries are a range of medical interventions performed in utero on the developing fetus of a pregnant woman to treat a number of congenital abnormalities. The first documented fetal surgical procedure occurred in ...

Anencephaly is an open neural tube defect, meaning that part of the neural tube does not properly close or that it has reopened during early embryogenesis. An embryo with anencephaly develops without the top of the skull, ...

Isotretinoin is a molecule and a byproduct (metabolite) of vitamin A, and in greater than normal amounts in pregnant women, it can cause fetal abnormalities including cleft lips, ear and eye defects, and mental retardation. ...

Vitamin A (retinol) is an essential vitamin in the daily functioning of human beings that helps regulate cellular differentiation of epithelial tissue. Studies have shown that an excess of vitamin A can affect embryonic ...

Fetus in fetu is a rare variety of parasitic twins , where the developmentally abnormal parasitic twin is completely encapsulated within the torso of the otherwise normally developed host twin. In the late eighteenth ...