Paul Ayuk

Placental Phenotypes of Intrauterine Growth

The placenta is essential to nutrition before birth. Recent work has shown that a range of clearly defined alterations can be found in the placentas of infants with intrauterine growth restriction (IUGR). In the mouse, a placental specific knockout of a single imprinted gene, encoding IGF-2, results in one pattern of alterations in placenta structure and function which leads to IUGR. We speculate that the alterations in the human placenta can also be grouped into patterns, or phenotypes, that are associated with specific patterns of fetal growth. Identifying the placental phenotypes of different fetal growth patterns will improve the ability of clinicians to recognize high-risk patients, of laboratory scientists to disentangle the complexities of IUGR, and of public health teams to target interventions aimed at ameliorating the long-term adverse effects of inadequate intrauterine growth.

Placental Transfer and Intrauterine Growth Restriction

During intrauterine life, the placenta undertakes some of the functions performed postnatally by the lungs, gut and kidneys - the absorption and transfer of oxygen and nutrients to the fetus, and the elimination of carbon dioxide and other metabolic wastes. These functions are self-evidently vital to normal intrauterine development. In postnatal life, disease processes that impair the absorptive and transport functions of the gut and lungs, or the ability of the kidneys to eliminate metabolic wastes, are important causes of failure to attain the genetic growth potential (failure to thrive). The hypothesis that a failure to attain the genetic growth potential in utero is associated with an impairment of the transport functions of the placenta is therefore a logical extension. This hypothesis is strengthened by the observations that the growth-restricted fetus is at increased risk of hypoxia [1,2], hypercapnia [1], acidaemia [1], hypoglycaemia [1-23] and hypoaminoacidaemia [1,3,4].

Misinformation about caesarean sections.

The caesarean section rate remains an issue for polarised debate. If Blustein and Liu are right,1 women are choosing to give birth by a more risky route. However, this debate usually comes with a fair dose of misinformation and opinion. These authors do not disappoint. Firstly, women with a previous caesarean do not have to decide between a caesarean …