Singleton Neonates Research Articles

Paid work, domestic work, and other determinants of pregnancy outcome in Ibadan, southwest Nigeria

Objective To identify the determinants of low birth weight (LBW), preterm birth, and stillbirth, and the factors associated with paid or domestic work that affected pregnancy outcome in Ibadan, Nigeria. Methods A cross-sectional study of women who delivered live or stillborn singleton neonates at 4 hospitals between February and June 2008. Participants were interviewed to obtain information on paid and domestic work activities during pregnancy, as well as obstetric history. Pregnancy outcomes and other clinical data were extracted from case notes. Results A total of 1504 mothers aged 20–45 years recorded 137 (9.1%) LBW neonates (< 2.5 kg), 154 (10.2%) preterm deliveries (< 37 weeks), and 56 (3.7%) stillbirths. There was no overall increased risk of these outcomes among working mothers. Multivariate logistic regression analysis of working mothers who had booked their deliveries revealed that lifting heavy objects at home, a clinical record of proteinuria, and hospital admission during pregnancy were associated with LBW. Predictors for preterm birth were self-reported exposure to vibration at work, nulliparity, history of preterm birth, 4 or fewer compared with more than 8 antenatal visits, and prolonged rupture of membranes. Predictors for stillbirth were low education and prolonged rupture of membranes. Conclusion The results further support recommendations that physical exertion in paid and domestic work should be reduced during pregnancy.

Impact of Labor on Outcomes in Transient Tachypnea of the Newborn: Population-Based Study

Transient tachypnea of the newborn (TTN) is the most common cause of neonatal respiratory distress; its estimated incidence is 1 % to 2%. Although a number of risk factors for TTN have been identified, the main risk factors include elective cesarean section (ECS), lower gestational age, male gender, and low birth weight. Previous studies have shown a positive impact of labor on respiratory outcomes among infants with TTN, but the impact of labor on the severity of TTN has not been investigated. This population-based cohort study investigated the effect of labor on the risk and course of TTN in a large, representative sample of term singleton neonates in Germany. Between 2001 and 2005, perinatal databases in the federal states of Hesse and Saarland were used to identify cases of TTN among singletons born at a gestational age ≥37 weeks, and to examine neonatal outcomes in all infants admitted to a neonatal center. Data for the TTN group was compared with national perinatal data for term singletons (control group) born during the study period. The International Classification of Diseases, 10th Revision was used to diagnosis TTN. Of the 239,971 term births included in the final analysis, 13,346 (5.6%) were transferred to a neonatal ward and 1423 (0.59%) cases of TTN were diagnosed. This represented an overall TTN incidence of 5.9 cases per 1000 singleton live births. Risk factors for TTN included ECS, low gestational age, male gender, and low birth weight. There was a significant association between the absence of labor before birth and longer duration of oxygen supplementation (P < 0.02), and an increased risk of TTN and severity of TTN at term. Prolonged labor reduced the need for oxygen supplementation and conversely, a decrease in labor duration increased the need (P < 0.028). These findings show that ECS and the absence of labor at term are strong risk factors for the development of TTN. Absence of labor or reduced labor duration is associated with increased severity of TTN and the need for oxygen supplementation.

Gestational age at glucocorticoids administration after premature rupture of membranes and cerebral white matter damage

Objective. We investigated whether gestational age at glucocorticoids administration in very preterm premature rupture of membranes (PROM) affects the occurrence of neonatal cerebral white matter damage (WMD).Methods. In a cohort of singleton neonates born at 24.0–33.6 weeks after PROM who underwent at least one full course of glucocorticoids (n = 130), we compared the gestational age at first and last course of glucocorticoids between those who developed WMD (n = 8) and those who did not (n = 122) after adjusting for gestational age at PROM using logistic regression with P < 0.05 considered significant.Results. Gestational age at first course of glucocorticoids (P = 0.2), at last course of glucocorticoids (P = 0.2) and at delivery (P = 0.2), were not significantly different between those who developed WMD and those who did not. Although latency between PROM and first course of glucocorticoids was protective against WMD (P = 0.02), the significance was lost after controlling for gestational age at PROM, which was significantly lower in cases that developed WMD (P < 0.01).Conclusions. In very preterm PROM, the beneficial effect of glucocorticoids on occurrence of WMD is not related to gestational age at steroid administration.

Omentin-1 and vaspin are present in the fetus and neonate, and perinatal concentrations are similar in normal and growth-restricted pregnancies

The aim of this study was to investigate circulating concentrations of omentin-1 and vaspin (adipocytokines predominantly secreted by visceral adipose tissue and not yet investigated in perinatal life) in maternal, fetal, and neonatal samples from intrauterine growth-restricted (IUGR; associated with altered development of adipose tissue) and appropriate-for-gestational-age (AGA) pregnancies and to correlate them with the respective insulin concentrations. Serum omentin-1 and vaspin concentrations were determined by enzyme immunoassay in 40 mothers and their 20 IUGR and 20 AGA singleton full-term fetuses and neonates on postnatal day 1 (N1) and day 4 (N4). Both hormones were detectable in fetal and neonatal blood (omentin-1 [mean ± SD, in nanograms per milliliter]: AGA vs IUGR group—fetal: 11.32 ± 1.88 vs 10.47 ± 1.30, N1: 10.74 ± 1.42 vs 10.46 ± 1.54, and N4: 10.90 ± 2.72 vs 11.35 ± 3.92; vaspin [median, minimum-maximum; in nanograms per milliliter]: AGA vs IUGR group—fetal: 0.39 [0.04-19.06] vs 0.40 [0.05-1.34], N1: 0.40 [0.04-16.70] vs 0.44 [0.23-3.34], and N4: 0.49 [0.02-8.89] vs 0.55 [0.06-3.92]). No significant differences in omentin-1 or vaspin concentrations were observed between IUGR and AGA groups, whereas fetal and N1 insulin concentrations were lower in the former ( P = .025 and P = .027, respectively). In both groups, fetal omentin-1 concentrations were higher ( P ≤ .018), whereas vaspin concentrations were lower ( P ≤ .001), than maternal ones. Furthermore, maternal vaspin concentrations were higher in cases of cesarean delivery ( P = .024). Omentin-1 and vaspin concentrations did not correlate with the respective insulin ones. In conclusion, omentin-1 and vaspin are present in the fetus and neonate. Perinatal concentrations of omentin-1 and vaspin are similar in IUGR cases and AGA controls—despite lower insulin concentrations in the former—and do not correlate with the respective insulin concentrations. Higher omentin-1 concentrations in the fetus may be crucial to enhance a growth-promoting effect, whereas lower maternal vaspin concentrations in cases of vaginal delivery may be attributed to spontaneous term delivery inflammation.

Neonatal outcome associated with singleton birth at 34-41 weeks of gestation

Approximately 75% of preterm births are late-preterm (34(0/7) to 36(6/7) weeks gestation). This group has usually been considered as a whole in studies assessing the outcome of these preterm infants by comparison with term infants. However, the respective contribution to prognosis of each week of gestation has not been fully clarified. A population-based study of 150 426 live-born singleton neonates with gestational ages ranging from 34 to 41 weeks of gestation. The rate of severe respiratory disorders (treated by mechanical ventilation and/or nasal continuous positive airway pressure) markedly declined with gestational age from 19.8% at 34 weeks to 0.28% at 39-41 weeks. Between 34 and 38 weeks, each additional week diminished the relative risk (crude or adjusted) of severe respiratory disorders by a factor varying from 2 to 3. The rate of poor prognosis (death and/or severe neurological condition) significantly declined between 34 and 38 weeks and remained stable thereafter. A multivariate analysis showed that antepartum haemorrhage and hypertensive disorders during pregnancy were significantly associated with severe respiratory disorders and poor outcome. Diabetes was an additional factor associated with severe respiratory disorders. Future studies should delineate more precisely the respective contribution of gestational age, maternal complication and induced delivery in the prognosis of infants born between 33 and 39 weeks gestation.

Trends in Birth Weight and Gestational Length Among Singleton Term Births in the United States

To estimate changes over time in birth weight for gestational age and in gestational length among term singleton neonates born from 1990 to 2005. We used data from the U.S. National Center for Health Statistics for 36,827,828 singleton neonates born at 37-41 weeks of gestation, 1990-2005. We examined trends in birth weight, birth weight for gestational age, large and small for gestational age, and gestational length in the overall population and in a low-risk subgroup defined by maternal age, race or ethnicity, education, marital status, smoking, gestational weight gain, delivery route, and obstetric care characteristics. In 2005, compared with 1990, we observed decreases in birth weight (-52 g in the overall population, -79 g in a homogenous low-risk subgroup) and large for gestational age birth (-1.4% overall, -2.2% in the homogenous subgroup) that were steeper after 1999 and persisted in regression analyses adjusted for maternal and neonate characteristics, gestational length, cesarean delivery, and induction of labor. Decreases in mean gestational length (-0.34 weeks overall) were similar regardless of route of delivery or induction of labor. Recent decreases in fetal growth among U.S., term, singleton neonates were not explained by trends in maternal and neonatal characteristics, changes in obstetric practices, or concurrent decreases in gestational length. III.

Malaria and stillbirth in Omdurman Maternity Hospital, Sudan

Objective The study was conducted in the labor ward of Omdurman Maternity Hospital, Sudan, from November 2007 to February 2008 to investigate the prevalence and risks factors for stillbirth. Methods A case-control study. Cases were women who delivered stillbirths; 2 consecutive women who delivered a live-born singleton neonate at term (37–42 weeks) per case were used as controls. Sociodemographic, clinical (including malaria infections), and obstetric histories were gathered using standard questionnaires. Maternal body mass index and hemoglobin levels were measured. Maternal, placental, and cord blood smears were investigated for malaria parasites. Results Among 4760 singleton deliveries, there were 103 stillbirths, yielding a stillbirth rate of 22 per 1000 deliveries. Over half (52.4%) of these stillbirths were macerated stillbirths. Maternal sociodemographic characteristics were not associated with stillbirth, while a history of maternal malaria in the index pregnancy was the main risk factor for stillbirth (odds ratio, 3.0; 95% confidence interval, 1.0–8.9; P = 0.04). Conclusion Measures to prevent malaria infection should help to prevent stillbirth in this part of Sudan.

Urgent Cesarean Delivery for Fetal Bradycardia

To estimate whether fetal bradycardia-to-delivery interval or decision-to-delivery interval was related to cord arterial pH according to different causes of fetal distress. Women who delivered singleton neonates by urgent cesarean delivery because of intrapartum fetal bradycardia were retrospectively categorized into three groups according to the cause of fetal bradycardia: 1) Irreversible; 2) Potentially Reversible; and 3) Unknown (no identifiable cause). Comparisons were made between groups in regard to pH, bradycardia-to-delivery interval, and decision-to-delivery interval. Correlation analyses between pH and both intervals were then performed for different groups. Of 235 cases, 39, 22, and 174 were respectively categorized into the Irreversible group, Potentially Reversible group, and Unknown group. The median pH was lower in the Irreversible group (7.094; interquartile range [IQR] 6.991-7.216) than in Potentially Reversible group (7.162; IQR 7.064-7.251) or Unknown group (7.210; IQR 7.161-7.255) (P<.001). The Irreversible group's median bradycardia-to-delivery interval was 5 minutes shorter than those of the other two groups (11 compared with 16.5 and 16 minutes, respectively; P<.001), whereas its median decision-to-delivery interval was 1 minute shorter (10 compared with 11.5 and 11 minutes, respectively; P=.001). In the Irreversible group, pH decreased with the bradycardia-to-delivery interval (Spearman's rho=-0.354; P=.027) at a rate of 0.011 per minute. Cord arterial pH did not correlate with the bradycardia-to-delivery interval in the Potentially Reversible and Unknown groups. In neither group did pH correlate with decision-to-delivery interval. Cord arterial pH deteriorates with bradycardia-to-delivery interval when the underlying cause of fetal distress is irreversible, but not so otherwise. II.

Soluble Fas Antigen and Soluble Fas Ligand in Intrauterine Growth Restriction

Background: The Fas-Fas ligand (FasL) pathway of apoptosis contributes to immune tolerance at the fetomaternal interface and has been ascribed a role in implantation and placental development. Intrauterine growth restriction (IUGR) may be associated with impaired maternal-fetal tolerance, resulting in increased trophoblast apoptosis and uteroplacental vascular insufficiency. Objectives: To investigate soluble Fas (sFas) and FasL (sFasL) concentrations in maternal, fetal and neonatal serum of IUGR and appropriate-for-gestational-age (AGA) pregnancies. Methods: Circulating sFas and sFasL concentrations were determined in 40 mothers and their 20 IUGR (due to several etiologies) and 20 AGA singleton full-term fetuses and neonates on postnatal day 1 (N1) and 4 (N4). Results: No significant differences in sFas and sFasL concentrations were observed between groups. In both groups, maternal sFas concentrations were increased compared to fetal, N1 and N4 ones (p≤0.005 in AGA and p < 0.001 in IUGR, in all cases). On the other hand, maternal sFasL concentrations were lower compared to fetal, N1 and N4 ones (p < 0.001 in all cases). Fetal sFasL concentrations were increased compared to maternal, but lower compared to N4 sFasL ones (p < 0.001 in AGA and p ≤ 0.020 in IUGR, in all cases). N4 sFasL concentrations were elevated compared to N1 ones (p < 0.001). Conclusions: Circulating maternal, as well as fetal sFas and sFasL concentrations do not differ between AGA controls and IUGR cases, irrespectively of the etiology of the latter. Furthermore, the results of this study imply an acceleration of Fas-FasL-mediated apoptosis during delivery and a respective decrease postpartum in both normal and IUGR pregnancies.

Neonatal outcomes of macrosomic births in diabetic and non-diabetic women

Objective:To compare the neonatal outcomes and birth injuries of macrosomic infants born to diabetic mothers (IDM) and non-diabetic mothers (non-IDM).Study design:This is a retrospective survey of all live born, singleton...

Disparities in Cesarean Delivery Rates and Associated Adverse Neonatal Outcomes in New York City Hospitals

To examine the primary cesarean delivery rates and associated neonatal outcomes by insurance status in public and private hospitals in New York City. We accessed Vital statistics data on all births to women with Medicaid or private insurance from 1996 through 2003, compiling a total of 321,308 nulliparous women who delivered singleton neonates by either normal spontaneous vaginal delivery or primary cesarean delivery. Rates of primary cesarean delivery and adverse neonatal outcomes were examined by hospital type and insurance status while controlling for potential confounders. There were 51,682 and 269,626 women who delivered in public hospitals and private hospitals, respectively. The cesarean delivery rate of women with private insurance delivering in private hospitals was 30.4% compared with a cesarean rate of 21.2% in Medicaid patients delivering in public hospitals (adjusted odds ratio [OR] 1.57, 95% confidence interval [CI] 1.53-1.63). The percent of infants born to women with private insurance and Medicaid delivering in private hospitals with a 5-minute Apgar score less than 7 was 0.6% and 0.8% compared with 1.0% of infants delivering in the public hospital system (adjusted OR 0.59, 95% CI 0.51- 0.68 and adjusted OR 0.73, 95% CI 0.65- 0.82). The neonatal intensive care unit admission rate was also lower in neonates born in private hospitals at 6.7% and 8.5% compared with a 12.8% admission rate in public hospitals (adjusted OR 0.48, 95% CI 0.46-0.51 and adjusted OR 0.59, 95% CI 0.57- 0.62 after controlling for mode of delivery). Even when controlling for confounders, there was an association between primary cesarean delivery and insurance status regardless of hospital type. There was also a higher risk of adverse neonatal outcomes in the public hospitals regardless of mode of delivery. III.

In Utero Gender Dimorphism of Adiponectin Reflects Insulin Sensitivity and Adiposity of the Fetus

Circulating adiponectin reflects the degree of energy homeostasis and insulin sensitivity of adult individuals. Low abundance of the high molecular weight (HMW) multimers, the most active forms mediating the insulin-sensitizing effects of adiponectin, is indicative of impaired metabolic status. The increase in fetal adiponectin HMW compared with adults is a distinctive features of human neonates. To further understand the functional properties of adiponectin during fetal life, we have evaluated the associations of adiponectin with insulin sensitivity, body composition, and gender. Umbilical cord adiponectin, adiponectin complexes, and metabolic parameters were measured at term by elective cesarean delivery. The associations between adiponectin, measures of body composition, and insulin sensitivity were evaluated in relation to fetal gender in 121 singleton neonates. Higher total adiponectin concentrations in female compared with male fetuses (34.3+/-9.5 vs. 24.9+/-8.6, P<0.001) were associated with a 3.2-fold greater abundance in circulating HMW complexes (0.20+/-0.03 vs. 0.08+/-0.03, P<0.001, n=9). Adiponectin was positively correlated with neonatal fat mass (r=0.27, P<0.04) and percent body fat in female fetuses (r=0.28, P<0.03) and with lean mass in males (r=0.28, P<0.03). There was no significant correlation between cord adiponectin and fasting insulin concentrations or fetal insulin sensitivity as estimated by homeostasis model assessment of insulin resistance (HOMA-IR). The gender dimorphism for plasma adiponectin concentration and complex distribution first appears in utero. In sharp contrast to the inverse correlation found in adults, the positive relationship between adiponectin and body fat is a specific feature of the fetus.

223: Short term outcomes in very low birthweight (VLBW) singleton neonates delivered breech: One center's experience

223: Short term outcomes in very low birthweight (VLBW) singleton neonates delivered breech: One center's experience

Quantitative bone US measurements in neonates and their mothers

Factors that affect quantitative ultrasound (QUS) bone measurements have not been clearly defined for all clinical populations. To determine some technical and clinical aspects that may affect QUS bone measurement in the neonate-maternal dyad. Speed of sound (SOS) was measured at the radius and tibia using a commercial multisite axial transmission QUS instrument and three manufacturer-provided probes (CS, CR and CM). The study included 183 singleton neonates and 159 mothers. The type of probe, weight and edema significantly affected SOS measurements. In infants, the CS and CR probes measured SOS consistently at the tibia but not the radius. Gestational age was predictive of SOS from the CS probe and remained significant when race, gender, and birth weight were included. None of these parameters predicted SOS when using the CR probe. Maternal SOS at the radius and tibia was correlated with the CM probe. Maternal SOS was predicted by age but not by gravid status, number of living children, or race. There was no consistent correlation between maternal-infant dyad SOS measurements. Axial transmission SOS of bone varies with probe and site and is affected by technical and clinical factors. Valid data depend on documentation of the probes used and the clinical population studied.

Which factors affect the occurrence of severe cerebral lesions in preterm neonates who are born with intrauterine infection?

The purpose of this study was to evaluate which factors affect the occurrence of neonatal ultrasonographic evidence of severe cerebral lesions in the presence of intrauterine infection. From a cohort of 567 singleton neonates who were born between 24.0 and 31.6 weeks of gestation, we identified the 180 infants with histologic and/or clinical evidence of intrauterine infection. We excluded stillbirths and congenital anomalies. Obstetric and neonatal variables were related to evidence of severe neonatal ultrasonographic cerebral lesions with the use of logistic regression analysis. Severe cerebral lesions were identified in 10% of infants (18/180). After we controlled for variables that were clinically relevant, logistic regression analysis demonstrated that ultrasound evidence of severe neonatal cerebral lesions was associated independently with antenatal administration of corticosteroids (adjusted odds ratio, 0.3; 95% CI, 0.11-0.88; P = .03) and occurrence of placental abruption (adjusted odds ratio, 5.4; 95% CI, 1.4-20.7; P = .02). Antenatal administration of corticosteroids in the presence of intrauterine infection has a protective effect on the risk of ultrasonographic evidence of severe neonatal cerebral lesions.

Incidence of Respiratory Disorders in Neonates Born between 34 and 36 Weeks of Gestation Following Exposure to Antenatal Corticosteroids between 24 and 34 Weeks of Gestation

We studied the effect of antenatal corticosteroids on the incidence of respiratory disorders in singleton neonates born between 34 and 36 weeks of gestation. Retrospective analysis was conducted of the incidence of respiratory distress syndrome (RDS) and other respiratory disorders (need for mechanical ventilation, continuous positive airway pressure, and prolonged oxygen therapy) among singleton neonates delivered between 34 and 36 weeks of gestation who were exposed to antenatal corticosteroids, compared with neonates who were not exposed. Statistical analyses included two-tailed T tests, two-way analysis of variance for continuous data, and chi-square analysis for ratios. A probability of 0.05 was considered significant. Between January 1, 2000, and December 31, 2004, 1078 neonates were born between 34 and 36 weeks of gestation. Information regarding antenatal corticosteroids was available in 1044: 574 neonates (53.2%) were exposed to antenatal corticosteroids and 470 (43.6%) were not. One thousand and eighteen neonates were admitted to the neonatal intensive care unit. Respiratory disorders were diagnosed in 140 of those exposed to antenatal steroids (24.4%) and in 382 of the nonexposed (81.3%) ( P < 0.0001). Two hundred and ten neonates (20.6%) developed RDS: Of those, 43 were exposed to antenatal corticosteroids and 167 were not (incidence of RDS was 7.5% and 35.5%, respectively; P = 0.0001). The beneficial effects of corticosteroids were similar in both genders. It appears that the exposure of singleton pregnancies to antenatal corticosteroids between 24 and 34 weeks of gestation is associated with a significantly lower incidence of respiratory disorders among neonates born at 34 to 36 weeks of gestation. Further studies are needed to determine whether administering antenatal steroids to women experiencing preterm labor after 34 weeks of gestation would be associated with a similar beneficial effect.

Bone Speed of Sound Curves of Twin and Singleton Neonates

To evaluate associations between prenatal risk factors, neonatal characteristics and bone development. Tibial speed of sound (SOS) of 317 neonates whose gestational ages ranged between 25 and 41 weeks and birth weight between 580 and 4,350 g was measured using quantitative ultrasound. Bone SOS values correlated significantly with gestational age and birth weight. Small for gestational age (SGA) infants had higher bone SOS values than appropriate for gestational age (AGA) infants. Infants born to multiple pregnancies had lower SOS values than singleton infants so two separate bone SOS curves were made: for singleton infants born AGA (n = 152), and for infants of multiple pregnancies born AGA (n = 104). Infants of preeclamptic mothers had significantly higher SOS values than the infants of mothers without preeclampsia. This is the first study reporting bone SOS values of Turkish neonates. Prenatal risk factors, such as preeclampsia, multiple pregnancy, and being SGA, affect the bone development of the fetus.

87: Which factor affect the occurrence of cerebral lesions in neonates born with intrauterine infection?

BORN WITH INTRAUTERINE INFECTION? ANNA LOCATELLI, MARIANNA ANDREANI, FRANCESCA ASSI, AGNESE PIZZARDI, SILVIA MALGUZZI, ALESSANDRO GHIDINI, University of Milano-Bicocca, Obstetrics and Gynecology, Monza, Italy, University of Milano-Bicocca, Neonatology, Monza, Italy OBJECTIVE: Intrauterine infection (II) is a risk factor for cerebral lesions (CL), and part of the damage seems to be attributed to the immune fetal response. We have evaluated which factor have an effect on neonatal ultrasonographic (US) evidence of CL in the presence of histological or clinical evidence of II. STUDY DESIGN: From a cohort of 567 consecutive singleton neonates born after preterm delivery at 24.0-31.6 weeks from 1/1993 to 12/2006 we selected 180 infants with histological and/or clinical evidence of II. Obstetric (gestational age, pregnancy complications, use of steroids and antibiotic, fetal distress, mode of delivery) and neonatal (sex, weight, Apgar score, pH, neonatal complications) were evaluated in reference to evidence of neonatal severe US CL, defined as IVH grade 3-4 and/or PVL. Excluded were stillbirths and congenital anomalies. Logistic regression analysis was used to control for confounders with P 0.05 considered significant. RESULTS: Table 1 Logistic regression analysis demonstrated that evidence of neonatal severe US CL is independently associated with antenatal administration of corticosteroids (OR 0.3, 95% CI 0.11, 0.88, P 0.03) and occurrence of abruptio placentae (OR 5.4, 95% CI 1.4, 20.7, P 0.02)

The True Incidence of Cryptorchidism in Denmark

Considerable controversy exists regarding the recently published high prevalence of cryptorchidism and the actual orchiopexy rate in Denmark. Therefore, we carried out another prevalence study. The study population included 1,094 consecutive males delivered alive at Glostrup University Hospital during 2002, with a 4-year review of patient data and telephone contact with primary physicians. At birth the overall frequency of cryptorchidism was 2.4% (26 of 1,088 cases, 23% bilateral). The frequency of cryptorchidism in singletons was 2.4% (24 of 1,012 patients). The frequency of cryptorchidism in patients with a birth weight of 2,500 gm or more was 2.1%, compared to 8.2% in those with a birth weight of less than 2,500 gm (chi-square p <0.05). The frequency of cryptorchidism in twins was 2.6% (2 of 76). The frequency of birth weight below 2,500 gm was 51% (39 of 76) in twins and 4.9% (50 of 1,012) in singletons (chi-square p <0.00005). The weight of the placenta was higher in twins (median 1,000 gm) than in singletons (650 gm). At age 4 years 1.6% of the boys had undergone or were waiting to undergo surgery for cryptorchidism, and 0.6% had a diagnosis of retractile testes. In a small cohort of newborns the incidence of cryptorchidism in Denmark has not changed, and is similar to previous reports from the 1950s. The risk is higher in low birth weight singleton neonates but does not appear to be higher in twins, despite lower birth weight and prematurity.

Circulating apelin concentrations in mother/infant pairs at term

To prospectively investigate circulating concentrations of the adipokine and angiogenic factor apelin in mother/infant pairs and correlate them with respective insulin concentrations. Plasma apelin concentrations were determined in 40 mothers and their singleton full-term foetuses and neonates on day 1 (N1) and 4 (N4) of life. Maternal apelin concentrations were lower compared to foetal, N1 and N4 ones (p<0.001 in all cases). N1 apelin concentrations were lower compared to foetal and N4 ones (p=0.002 and p=0.005, respectively). Maternal apelin concentrations positively correlated with foetal, N1 and N4 concentrations (r=0.663, p<0.001, r=0.486, p=0.003, r=0.484, p=0.003, respectively). Foetal apelin concentrations positively correlated with N1 and N4 ones (r=0.337, p=0.044 and r=0.574, p<0.001, respectively). N1 apelin concentrations positively correlated with N4 ones (r=0.513, p=0.001). No association was found between apelin concentrations and birthweight, gender, parity or mode of delivery. No significant correlations were observed between apelin and insulin concentrations. Concentrations of apelin are high in the foetus, possibly suggesting its potential role in intrauterine development. Apelin expression in placental tissue could account for its higher foetal concentrations and for its down-regulation soon after birth. The postnatal increase of apelin concentrations could presumably point to a gradual initiation of ex utero angiogenesis.