Preterm birth and reduced birthweight in first and second teenage pregnancies: a register-based cohort study.

BACKGROUND: Higher risks of preterm birth and small for gestational age babies have been reported in teenagers. The aim of this study was to investigate the relationship between first and second teenage pregnancies and preterm birth, birthweight and small for gestational age (SGA). METHODS: All women aged 14 to 29 yrs who gave birth to live singletons in the North Western Region of England between January 1st 2004 and December 31st 2006 were identified. Women were classified in three groups; 14-17 yrs, 18-19 yrs and 20-29 yrs (reference group). The outcome measures were preterm birth, very preterm birth, birthweight, SGA (< 5th percentile), very SGA (VSGA< 3rd percentile). We compared these outcome measures in teenagers' first and second pregnancies with those of mothers aged 20 to 29 yrs. RESULTS: The risk of preterm birth was increased in first (OR = 1.21, [95% CI: 1.01-1.45]) and second (OR = 1.93, [95% CI: 1.38-2.69]) time mothers aged 14-17 yrs compared to the reference group. Birthweight was reduced in the first (mean difference = -24 g; [95% CI: -40, -7]) and second (mean difference = -80 g; [95% CI: -115, -46]) time mothers aged 14-17 yrs compared to the reference group. There was some evidence of a protective effect against VSGA in 14-17 yr old first time mothers (OR = 0.79, [95% CI: 0.63-0.99]). CONCLUSIONS: Teenage mothers are at increased risk of preterm birth compared to adult mothers and this risk is further increased in second time teen pregnancies. This study highlights the importance of ensuring pregnant teenagers have appropriate antenatal care. A first pregnancy may be the first and only time a pregnant teenager interacts with health services and this opportunity for health education and the promotion of contraception should not be overlooked

Current challenges in pregnancy-related mortality

Pregnancy is a normal, healthy state that most women are desirous for at some point in their lives. Sadly, this life-affirming process carries serious risks of death and disability for both mother and offspring. It is estimated that about 830 women die from pregnancy or pregnancy related complications each year. Almost all of these deaths occur in resource-poor countries, and most of them are preventable. Reducing maternal mortality is an ongoing challenge, and care providers, researchers and policy makers must not only identify the key barriers to accessing quality health care, but commit to making maternal health a priority

A novel method for interrogating receiver operating characteristic curves for assessing prognostic tests.

Background: Disease prevalence is rarely explicitly considered in the early stages of the development of novel prognostic tests. Rather, researchers use the area under the receiver operating characteristic (AUROC) as the key metric to gauge and report predictive performance ability. Because this statistic does not account for disease prevalence, proposed tests may not appropriately address clinical requirements. This ultimately impedes the translation of prognostic tests into clinical practice. Methods: A method to express positive- and/or negative predictive value criteria (PPV, NPV) within the ROC space is presented. Equations are derived for so-called equi-PPV (and equi-NPV) lines. Herewith it is possible, for any given prevalence, to plot a series of sensitivity-specificity pairs which meet a specified PPV (or NPV) criterion onto the ROC space.This concept is introduced by firstly reviewing the well-established "mechanics", strengths and limitations of the ROC analysis in the context of developing prognostic models. Then, the use of PPV (and/or) NPV criteria to augment the ROC analysis is elaborated.Additionally, an interactive web tool was also created to enable people to explore the dynamics of lines of equi-predictive value in function of prevalence. The web tool also allows to gauge what ROC curve shapes best meet specific positive and/or negative predictive value criteria (http://d4ta.link/ppvnpv/). Results: To illustrate the merits and implications of this concept, an example on the prediction of pre-eclampsia risk in low-risk nulliparous pregnancies is elaborated. Conclusions: In risk stratification, the clinical usefulness of a prognostic test can be expressed in positive- and negative predictive value criteria; the development of novel prognostic tests will be facilitated by the possibility to co-visualise such criteria together with ROC curves. To achieve clinically meaningful risk stratification, the development of separate tests to meet either a pre-specified positive value (rule-in) or a negative predictive value (rule-out) criteria should be considered: the characteristics of successful rule-in and rule-out tests may markedly differ

Maternal Dietary Patterns and Pregnancy Outcome

Maternal nutritional status during pregnancy will affect the outcomes for the mother and the baby. Many analyses of the relationship between diet and outcome are often based on a single or a few food items or nutrients. However, foods are not consumed in isolation and dietary patterns can be used to assess the whole diet consumed. The use of dietary pattern analysis to understand nutritional intake and pregnancy outcome is becoming more and more popular. Many published studies have showed the association between maternal dietary patterns and pregnancy outcome. This review examined articles about the relationship between maternal dietary patterns and pregnancy outcome. As a modifiable factor, dietary patterns may be more applicable to clinical and pregnant health interventions

Kaplan-Meier plot estimates of anaemia status and gestational age at delivery.

<p>(Note the ‘curious’ behaviour of women with moderate anaemia who have no pre-term birth and are on average—median and mean—delivering later than women with mild anaemia and even those with no anaemia—median.).</p

Human Placental Growth Hormone Variant in Pathological Pregnancies

Growth hormone (GH), an endocrine hormone primarily secreted from the anterior pituitary, stimulates growth, cell reproduction and regeneration and is a major regulator of postnatal growth. Humans have two GH genes which encode two versions of GH proteins: a pituitary version (GH-N/GH1), and a placental GH variant (GH-V/GH2) which is expressed in the syncytiotrophoblast and extravillous trophoblast cells of the placenta. During pregnancy, placental GH replaces pituitary GH in the maternal circulation at mid-late gestation as the major circulating form of GH. This remarkable change in spatial and temporal GH secretion patterns is proposed to play a role in mediating maternal adaptations to pregnancy. Placental GH is associated with fetal growth and its circulating concentrations have been investigated across a range of pregnancy complications. However, progress in this area has been hindered by a lack of readily accessible and reliable assays for measurement of placental GH. This review will discuss the potential roles of placental GH in normal and pathological pregnancies and will touch on the assays used to quantify this hormone

Maternal Dietary Patterns and Pregnancy Outcome

Maternal nutritional status during pregnancy will affect the outcomes for the mother and the baby. Many analyses of the relationship between diet and outcome are often based on a single or a few food items or nutrients. However, foods are not consumed in isolation and dietary patterns can be used to assess the whole diet consumed. The use of dietary pattern analysis to understand nutritional intake and pregnancy outcome is becoming more and more popular. Many published studies have showed the association between maternal dietary patterns and pregnancy outcome. This review examined articles about the relationship between maternal dietary patterns and pregnancy outcome. As a modifiable factor, dietary patterns may be more applicable to clinical and pregnant health interventions

Maternal Administration of Sildenafil Citrate Alters Fetal and Placental Growth and Fetal-Placental Vascular Resistance in the Growth-Restricted Ovine Fetus

Intrauterine growth restriction (IUGR) causes short- and long-term morbidity. Reduced placental perfusion is an important pathogenic component of IUGR; substances that enhance vasodilation in the uterine circulation, such as sildenafil citrate (sildenafil), may improve placental blood flow and fetal growth. This study aimed to examine the effects of sildenafil in the growth-restricted ovine fetus. Ewes carrying singleton pregnancies underwent insertion of vascular catheters, and then, they were randomized to receive uterine artery embolization (IUGR) or to a control group. Ewes in the IUGR group received a daily infusion of sildenafil (IUGR+SC; n=10) or vehicle (IUGR+V; n=8) for 21 days. The control group received no treatment (n=9). Umbilical artery blood flow was measured using Doppler ultrasound and the resistive index (RI) calculated. Fetal weight, biometry, and placental weight were obtained at postmortem after treatment completion. Umbilical artery RI in IUGR+V fell less than in controls; the RI of IUGR+SC was intermediate to that of the other 2 groups (mean±SEM for control versus IUGR+V versus IUGR+SC: ∆RI, 0.09±0.03 versus -0.01±0.02 versus 0.03±0.02; F(2, 22)=4.21; P=0.03). Compared with controls, lamb and placental weights were reduced in IUGR+V but not in IUGR+SC (control versus IUGR+V versus IUGR+SC: fetal weight, 4381±247 versus 3447±235 versus 3687±129 g; F(2, 24)=5.49; P=0.01 and placental weight: 559.7±35.0 versus 376.2±32.5 versus 475.2±42.5 g; F(2, 24)=4.64; P=0.01). Sildenafil may be a useful adjunct in the management of IUGR. An increase in placental weight and fall in fetal-placental resistance suggests that changes to growth are at least partly mediated by changes to placental growth rather than alterations in placental efficiency

G-protein-coupled receptor 30 mediates the effects of estrogen on endothelial cell tube formation in vitro

The placenta is the exchange organ between the mother and the fetus. The inadequate function of this organ is associated with a number of pregnancy disorders. Hypoxia and oxidative stress during placental development may induce endothelial dysfunction, resulting in the reduction in the perfusion of the placenta. During pregnancy, the levels of estrogen are increased. Decreased estrogen levels have been reported in women with preeclampsia. However, whether estrogen is involved in placental angiogenesis remains unclear. In this study, we aimed to investigate the effects of estrogen on endothelial cell tube formation and to elucidate the underlying mechanisms. For this purpose, human umbilical vein endothelial cells (HUVECs) were cultured with 17‑β‑estradiol under conditions of hypoxia/reoxygenation (H/R). The total pipe length of the tube‑like structure on endothelial cells was measured. The expression levels of G‑protein‑coupled receptor 30 (GPR30) and endothelial nitric oxide synthase (eNOS) and Akt were also measured in the endothelial cells following treatment with 17‑β‑estradiol under H/R conditions by western blot analysis and immunostaining. We found that the total pipe length of the tube‑like structure on endothelial cells was significantly reduced. This reduction was reversed by treatment with 17‑β‑estradiol. The expression of GPR30 in endothelial cells was significantly increased following treatment with 17‑β‑estradiol under H/R conditions. Furthermore, the levels of eNOS and Akt in endothelial cells were also significantly increased following treatment with 17-β-estradiol under H/R conditions. The activation of eNOS was inhibited by wortmannin, an inhibitor of PI3K/Akt. Our data thus demonstrate that estrogen prevents the failure of endothelial cell tube formation induced by H/R. GPR30 plays an important role in these protective effects through the activation of eNOS and Akt in endothelial cells. Our data suggest that increased levels of estrogen are important for placental angiogenesis

Comparison of participants without and with anaemia.

<p>^a The presence or absence of anaemia was adjusted for smoking</p><p>^b Pearson’s χ² test or Fisher's exact test</p><p>^c Mann-Whitney test</p><p>* p-value < 0.002 was considered statistically significant</p><p>Comparison of participants without and with anaemia.</p