Oxidative stress early in pregnancy and pregnancy outcome

The objectives of this study were to determine whether oxidative stress early in pregnancy influenced pregnancy outcome. A combination of assays were used for exogenous and endogenous anti-oxidants together with two well accepted biomarkers for oxidative stress, the urinary excretion of 8-iso-PGF_2α (a biomarker marker for lipid oxidation, n=508) and 8-oxo-7,8 dihydro-2 deoxyguanosine (8-OHdG, a biomarker for DNA oxidation, n=487). The two biomarkers tracked different pregnancy outcomes. Isoprostanes were associated with an increased risk of pre-eclampsia and a decreased proportion of female births. In contrast, 8-OHdG tracked lower infant birthweight and shortened gestation duration. Birth defects were associated with low levels of 8-OHdG.     

Oxidative stress early in pregnancy and pregnancy outcome

The objectives of this study were to determine whether oxidative stress early in pregnancy influenced pregnancy outcome. A combination of assays were used for exogenous and endogenous anti-oxidants together with two well accepted biomarkers for oxidative stress, the urinary excretion of 8-iso-PGF(2alpha) (a biomarker marker for lipid oxidation, n=508) and 8-oxo-7,8 dihydro-2 deoxyguanosine (8-OHdG, a biomarker for DNA oxidation, n=487). The two biomarkers tracked different pregnancy outcomes. Isoprostanes were associated with an increased risk of pre-eclampsia and a decreased proportion of female births. In contrast, 8-OHdG tracked lower infant birthweight and shortened gestation duration. Birth defects were associated with low levels of 8-OHdG.     

Poliomyelitis in pregnancy

Acute poliomyelitis occurs in all trimesters of pregnancy. At one time there were six women in the poliomyelitis ward at Children's Hospital, five of whom were either pregnant or recently delivered. Poliomyelitis is an important entity in the differential diagnosis of diseases complicating pregnancy. Once diagnosed, treatment is directed primarily toward the symptoms of poliomyelitis, secondarily toward pregnancy. Effort should be made to maintain adequately high oxygen tension in the maternal blood stream to protect the fetus. The prognosis of the disease when it occurs during pregnancy may be less predictable, but it is generally good for both mother and infant. Although the incidence of abortion is relatively high, if the pregnancy goes to term parturition is expected to be normal. The number of cases reported is not sufficient to establish the significance of the suspected selective occurrence of poliomyelitis in pregnancy.     

Leptin in pregnancy

Leptin is a polypeptide hormone that aids in the regulation of body weight and energy homeostasis and is linked to a variety of reproductive processes in both animals and humans. Thus, leptin may help regulate ovarian development and steroidogenesis and serve as either a primary signal initiating puberty or as a permissive regulator of sexual maturation. Perhaps significantly, peripheral leptin concentrations, adjusted for adiposity, are dramatically higher in females than in males throughout life. During primate pregnancy, maternal levels that arise from adipose stores and perhaps the placenta increase with advancing gestational age. Proposed physiological roles for leptin in pregnancy include the regulation of conceptus growth and development, fetal/placental angiogenesis, embryonic hematopoiesis, and hormone biosynthesis within the maternal-fetoplacental unit. The specific localization of both leptin and its receptor in the syncytiotrophoblast implies autocrine and/or paracrine relationships in this endocrinologically active tissue. Interactions of leptin with mechanisms regulating pre-eclampsia and maternal diabetes have also been suggested. Collectively, therefore, reports suggest that a better understanding of the regulation of leptin and its role(s) throughout gestation may eventually impact those causes of human perinatal morbidity and mortality that are exacerbated by intrauterine growth retardation, macrosomia, placental insufficiency, or prematurity.     

Interferon in pregnancy

The cells of the immune system exchange information by a complex network of molecules referred to as lymphokines: these include the interferons. The physiology of the interferons, both in terms of control and function, is poorly understood. However, there is ample evidence that production of alpha-interferon is characteristic of the fetoplacental unit in both the human and other species. Indeed, the major trophoblast protein in early pregnancy in the sheep is alpha-interferon and in this species the molecule appears to have an important anti-luteolytic effect. The function of the interferons in human pregnancy is not known but, by analogy with information from other experimental systems, it might reflect aspects of the immune relationship between the mother and the fetus.     

HO in pregnancy

The enzyme heme oxygenase (HO) has been implicated in several physiological functions throughout the body including control of vascular tone and regulation of the inflammatory and apoptotic cascades as well as contributing to the antioxidant capabilities in several organ systems. These various properties attributed to HO are carried out through the catalytic products of heme degradation, namely carbon monoxide (CO), biliverdin, and free iron (Fe2+). As the newly emerging roles of HO in normal organ function have come to light, researchers in several disciplines have assessed the role of this enzyme in various physiological and pathological changes taking place in the human body over a lifetime. Included in this new wave of interest is the involvement of HO, and its by-products, in the normal function of the vital organ of pregnancy, the placenta. In this review the role of HO, and its catalytic products, will be examined in the context of pregnancy. The different isoforms of the HO enzyme (HO-1, HO-2, HO-3) have been localized throughout placental tissue, and have been shown to be physiologically active. The HO protein and more specifically its catalytic by-products (CO, biliverdin, and Fe2+) have been postulated to be involved in the maintenance of uterine quiescence throughout gestation, regulation of hemodynamic control within the uterus and placenta, regulation of the apoptotic and inflammatory cascades in trophoblast cells, and the maintenance of a balance of the oxidant-antioxidant status within the placental tissues. The association between this enzyme system, and its above-noted roles throughout pregnancy, with the hypertensive disorder of pregnancy preeclampsia (PET), will also be examined. It is hypothesized that a decrease in HO expression and/or activity throughout gestation would be capable of initiating several pathological processes involved in the etiology of PET. This hypothesis has led to further discussion emphasizing the possibility of novel therapeutic designs targeting this enzyme system for the treatment of PET.     

Loss in higher multiple pregnancy and multifetal pregnancy reduction.

From early pregnancy into childhood, higher multiples have much higher rates of mortality, whether from spontaneous abortion, the 'vanishing twin' syndrome, fetal or infant death. Many parents must cope with the death of one baby whilst the siblings remain critically ill or later become disabled and yet there grief is often underestimated. Little is known about the long term feelings of parents who choose to have a multifetal pregnancy reduction (MFPR). Most say they made the right decision but also that there was insufficient respect for their loss. They are often anxious about what, if anything, to tell the survivors and how they might react. Long term follow-up studies of the children as well as the parents are needed. Meanwhile parents who chose to have a MFPR must be given more information and ongoing support.