Comparison of hematological parameters between single and twin pregnancies in Dorper ewes during gestation, lambing, and postpartum / Comparação dos parâmetros hematológicos entre ovelhas Dorper de gestação simples e gemelar durante a prenhez, parto e pós-parto

ABSTRACT: The hematopoietic system changes during the pregnancy to carry fetal development and maternal needs. This study compared the hematological parameters between ewes with single and twin pregnancies during gestation, delivery, and postpartum. The experiment was conducted on 60 healthy pregnant Dorper ewes that were divided into two experimental groups: Group 1 (G1), with single pregnancies (n=30), and Group 2 (G2), with twin pregnancies (n=30). Blood samples were collected from all ewes at different times: immediately before fixed-time artificial insemination (AI); on day 30, 90, 120, 130, and 140 of pregnancy; immediately after delivery; and at 24h and 48h postpartum. Statistical analysis compared the two groups at different times (P<0.05). Mild, normocytic, and hypochromic anemia was detected in all ewes from AI time and throughout pregnancy from both groups, but did not prove to be of clinical relevance. In the peripartum stage (from the 140th day of pregnancy to 48h postpartum), the ewes with twin pregnancies (G2) exhibited higher erythrogram values and neutrophil:lymphocyte ratio than did ewes with single pregnancies (G1). This indicated a greater hematopoietic adaptation in the body during the development of two fetuses. Except for the eosinophil numbers, all leukogram parameters were influenced by pregnancy in a similar way in both groups, and was characterized mainly by leukocytosis with neutrophilia during peripartum due to the high presence of endogenous cortisol at delivery. Thus, these findings showed that pregnancy was a stressful physiological event that increased the leukocyte count with a slight alteration in the erythrogram of Dorper ewes.

RESUMO: O sistema hematopoiético sofre mudanças durante a gestação para atender o desenvolvimento fetal e as necessidades maternas. Este estudo comparou os parâmetros hematológicos entre ovelhas com gestação simples e gemelar durante a prenhez, parto e pós-parto. O estudo foi realizado em 60 ovelhas Dorper prenhes, saudáveis, divididas em dois grupos experimentais: Grupo 1 (G1) com gestação simples (n = 30); e Grupo 2 (G2) com gestação gemelar (n = 30). Amostras de sangue foram colhidos de todas as ovelhas em diferentes momentos: imediatamente antes da inseminação artificial em tempo fixo (IA); nos dias 30, 90, 120, 130 e 140 de gestação; imediatamente após o parto; e às 24h e 48h pós-parto. A análise estatística comparou os dois grupos nos diferentes momentos (P < 0,05). Anemia leve, normocítica e hipocrômica foi detectada desde a IA e ao longo da gestação, nas ovelhas de ambos os grupos, mas não houve relevância clínica. Na fase periparto (do 140º dia de gestação às 48h pós-parto), as ovelhas com gestação gemelar (G2) mostraram valores do eritrograma e proporção neutrófilos: linfócitos mais elevados do que as ovelhas com gestação simples (G1). Isso indicou maior adaptação hematopoiética da ovelha para o desenvolvimento de dois fetos. Com exceção do número de eosinófilos, todos os parâmetros do leucograma foram influenciados pela gestação de forma semelhante em ambos os grupos, e foi caracterizada principalmente por leucocitose com neutrofilia no periparto devido ao alto nível de cortisol endógeno no parto. Assim, os achados mostraram que a gestação foi um evento fisiológico estressante que aumentou a contagem de leucócitos com leve alteração no eritrograma de ovelhas Dorper.

Comparison of electrolyte and acid-base balances of Dorper breed ewes between single and twin pregnancies / Comparação dos equilíbrios eletrolítico e ácido básico de ovelhas da raça Dorper entre gestação única e gemelar

During pregnancy there are modifications in the metabolic profile of sheep that may predispose to the occurrence of metabolic disorders, of which pregnancy toxaemia (PT) is highlighted. Blood gas analysis is detects changes in acid-base and electrolyte balance effectively. The objectives of this study were to study the acid-base and electrolyte balance of sheep during gestation and in the immediate peripartum (up to 48 hours postpartum), comparing single gestation with twins. Sixty healthy sheep of Dorper breed, two to five years old were raised in a semi-intensive system and were divided in two experimental groups: Group 1: 30 ewes, with ultrasonographic diagnosis of single fetus gestation; Group 2: 30 ewes, with ultrasonographic diagnosis of twin pregnancy. The experimental moments were defined as: MI-immediately after artificial insemination (control); MG30 - 30 days of gestation; MG90 - 90 days of gestation; MG120 - 120 days of gestation; MG130 - 130 days of gestation; MG140 - 140 days of gestation; MP - lambing; MPP1 - 24h postpartum; MPP2 - 48h postpartum. At all times 1mL of blood was collected per jugular vein puncture for blood gas evaluation in a portable equipament (I-Stat®). The pH, carbon dioxide pressure (PCO2), bicarbonate (HCO3-), base excess (BE), sodium (Na+), potassium (K+), chloride (Cl-), ionized calcium (Ca+2), lactate, anion gap (AG) were mensured and strong ion difference (SID) were calculed. This work showed that there were changes in acid-base and electrolyte balance in pregnant ewes, due to the decrease in BE, HCO3-, TCO2 and increase of lactate and AG during gestation, but the pH remained normal and did not present any difference among moments in both groups. Comparing the groups, single-gestation ewes presented higher alkaline expenditure at delivery than twin-gestation, evidenced by lower levels of BE and HCO3-. Lower Na+ levels were observed in prepartum; drop in K+ values with advancing gestation; hyperchloremia and hypocalcemia during gestation according to the reference standards for species; decreased iCa+2 levels in the final third of gestation in both groups. It was concluded that the ewes of this study were healthy until the last moment analyzed (48h postpartum), although have shown greater consumption of the alkaline reserve in the peripartum, being more explicit in the single gestation animals. In addition, this situation can be physiological and result in increased energy demand during gestation, more exacerbated by peripartum.(AU)

Durante a gestação ocorrem modificações metabólicas nas ovelhas que podem predispor a ocorrência de transtornos metabólicos, dos quais se destaca a toxemia da prenhez (TP). A hemogasometria é um exame que detecta alterações nos equilíbrios ácido-básico e eletrolítico de forma eficaz. Os objetivos deste estudo foram estudar os equilíbrios ácido-básico e eletrolítico de ovelhas durante a gestação e no periparto imediato (até 48 horas pós-parto), comparando-se gestação única com gemelar. Foram utilizadas 60 ovelhas criadas em manejo semi-intensivo, hígidas, da raça Dorper, com dois a cinco anos de idade. Foram constituídos dois grupos experimentais: Grupo 1: 30 ovelhas, com diagnóstico ultrassonográfico de gestação de feto único; Grupo 2: 30 ovelhas, com diagnóstico ultrassonográfico de gestação gemelar. Os momentos experimentais foram definidos como: MI - imediatamente após a inseminação artificial (controle); MG30 - 30 dias de gestação; MG90 - 90 dias de gestação; MG120 - 120 dias de gestação; MG130 - 130 dias de gestação; MG140 - 140 dias de gestação; MP - dia do parto; MPP1 - 24h pós-parto; MPP2 - 48h pós-parto. Em todos os momentos foi colhido 1mL de sangue por punção da veia jugular para avaliação hemogasométrica em aparelho portátil (I-Stat®). Foram analisados os parâmetros: pH, pressão de dióxido de carbono (PCO2), bicarbonato (HCO3-), excesso de bases (EB), sódio (Na+), potássio (K+), cloreto (Cl-), cálcio ionizado (iCa+2), lactato, ânion gap (AG) e diferença de íons fortes (SID). Este trabalho mostrou que houve mudanças nos equilíbrios ácido-básico e eletrolítico nas ovelhas prenhes, pela diminuição do EB, HCO3- e aumento do lactato e AG no decorrer da gestação, porém o pH se manteve dentro da normalidade e não apresentou diferença ao longo dos momentos em ambos os grupos. Comparando os grupos, as ovelhas de gestação única apresentaram maior consumo da reserva alcalina no momento do parto do que as de gestação gemelar, evidenciado menores níveis de EB e HCO3-. Foram observados níveis mais baixos de Na+ no pré-parto; queda dos valores de K+ com o avanço da gestação; hipercloremia e hipocalcemia durante a gestação segundo os padrões de referência para espécie e diminuição dos níveis de iCa+2 no terço final da gestação nas ovelhas de ambos os grupos. Concluiu-se que as ovelhas deste estudo apresentaram-se saudáveis até o último momento analisado (48h pós-parto), embora tenham mostrado maior consumo da reserva alcalina no periparto, sendo mais evidente nos animais de gestação única. Apesar disso, essa ocorrência pode ser considerada fisiológica e consequência do aumento da demanda energética durante a gestação, mais exacerbada no periparto.(AU)

Pregnancy outcome according to gestational weight gain in twin pregnancies on the basis of the 2009 Institute of Medicine (IOM) recommendations / 대한산부인과학회지

OBJECTIVE: The aim of this study was to investigate the effect of gestational weight gain on pregnancy outcome in twin pregnancies according to prepregnancy body mass index (BMI), on the basis of 2009 Institute of Medicine (IOM) recommendations. METHODS: One hundred ninety-eight twin pregnancy women and their 396 neonates who delivered in Yonsei University Health System from January 1st, 2005 to April 30th, 2010. Maternal height, maternal weight in prepregnancy and gestational weight gain were retrospectively reviewed. Women were grouped into four categories of BMI: underweight ( or =30 kg/m2). Gestational weight gain was categorized as "Less" if it was below the IOM's recommended range for the woman's prepregnancy BMI, "Within" if it was within the range, and "More" if it was above the range. RESULTS: Underweight with "Less" or "Within" maternal weight gain groups were associated with significantly increased odds for small for gestational age ("Less", odds ratio [OR] 6.5, confidence interval [CI] 1.75~24.14; "Within", OR 3.55, CI 1.37~9.14) and "More" weight gain with overweight or obesity groups were associated with significantly increased odds for large for gestational age (overweight, OR 6.25, CI 1.14~34.32; obesity, OR 8.33, CI 1.14~47.93). Overweight or obese women and excessive gestational weight gain were associated with significantly increased odds of pregnancy induced hypertension (overweight: OR 7.04, CI 1.04~47.78, obesity: OR 10.56, CI 1.32~84.14) and gestational diabetes mellitus (overweight: OR 13.2, CI 1.78~97.74, obesity: OR 19.8, CI 2.29~171.02). CONCLUSION: Overweight or obese women with excessive gestational weight gain were associated with significantly increased risk of adverse pregnancy outcome in twin pregnancies. Therefore, physician should pay attention not only to prepregnancy BMI but also to maternal weight gain. A large prospective study is necessary to confirm the relationships between gestational weight gain and pregnancy outcome in twin pregnancies.

Outcome of Surviving Twins with Antenatal Death of the Co-Twin: Comparison with Normal Twins

PURPOSE: In twin pregnancies with single fetal death after 20th weeks, the surviving co-twin has an ischemic change of multiple organ, neurological abnormality, high perinatal morbidity and mortality. The purpose of this study was to evaluate the clinical status and the outcome of live co-twins and to compare them with the normal viable twins. METHODS: A retrospective analysis by evaluating medical records was done for those twin pregnancies with single fetal demise after 20 weeks (n=20) during January 2000 to June 2003 at Samsung Cheil Hospital. Normal viable twins (n=847) born during the same study period were used as a control group. RESULTS: 867 of 31, 219 live deliveries were documented as twin births. 20 twin pregnancies were complicated by the death of one fetus after 20th weeks. In these 20 twin pregnancies, two surviving co-twins died after birth. There was an increased incidence of monochorionic placenta, prematurity, VLBW (very low birth weight), admission rate in neonate and mortality among the surviving co-twins as compared to the normal viable twins (P<0.001). However, there was no significant difference between surviving co- twins with dichorionic placenta and normal viable twins. CONCLUSION: The perinatal morbidity and mortality of surviving twins were higher than the normal twins in the monochorionic twins whose co-twin's death occurred after 20th weeks suggests that chorionicity of placenta might be an important factor to predict the outcome of surviving co-twin's.

Retrospective analysis of fetoscopic photocoagulation of communicating placental vessels of twin-twin transfusion syndrome / 第三军医大学学报

Objective To investigate the effect of fetoscopic photocoagulation of communicating placental vessels in twin-twin transfusion syndrome(TTTS)(selective or non-selective) on the perinatal outcomes.Methods Six cases of TTTS admitted in our department from Dec.2006 to Jun.2008 underwent fetoscopic photocoagulation of communicating vessels.Under direct real-time sonographic guidance,a 3-mm-diameter fetoscope was percutaneously inserted through the maternal abdominal wall into the amniotic cavity of the recipient twin.A combination of ultrasonographic and fetoscopic vision was used to identify the crossing vessels which were systematically coagulated using Nd:YAG laser fiber or bipolar electrocoagulation.Results All the 6 mothers tolerated the procedure without major complications.Two fetal survival rate was 33.33%.Conclusion Fetoscopic photocoagulation of communicating placental vessels in TTTS can effectively improve perinatal outcomes.

Effects of Single Fetal Death on Mother and Live Co-twin in Twin Pregnancy

PURPOSE: Twins have a higher mortality and morbidity than singletons. Co-twin with one fetal death is particularly at risk. We investigated the neonatal outcome of live co-twins when one fetus had died after the 20th gestational week, and associated risk factors. METHODS: A retrospective study was performed in fifteen cases of twin pregnancy with single intrauterine fetal deaths after the 20th gestational week during the period from January 1996 to December 2000 at Chonnam University Hospital. RESULTS: Gestational age was 33.7+/-3.2 weeks, birth weight was 1,992+/-592 g. Interval between one fetal death being detected and the delivery of a live co-twin was 32.4+/-29.5 days. There were 11 cases(73.3%) of premature babies less than 37 gestational weeks. Main causes of preterm delivery were preterm labor and premature rupture of membranes. Hematologic findings suggesting disseminated intravascular coagulopathy(DIC) were not found in all mothers before delivery, and was not associated with DIC and encephalomalacia of the live co-twin. Perinatal outcome of fifteen live co-twins was as follows : six were normal(40%), three were DIC(20.0%), three were encephalomalacia(20.0%), one suffered intrauterine growth retardation, there was one case of twin to twin transfusion syndrome, and one of congenital heart disease(atrial septal defect with pulmonary stenosis). The occurrence of DIC and encephalomalacia in live co-twins was not related to placental chorionicity, birth weight, gestational week, and the interval between the detection one fetal death and the delivery of a live co-twin. CONCLUSIONS: We could not find any maternal hematologic problems in twin pregnancies complicated by one fetal death. Twenty percent of live co-twins showed DIC and encephalomalacia. However, its associated risk factors were not found. We need to investigate more closely the cases of live co-twins with one intrauterine fetal death.

Birthweight and growth discordancy in twin pregnancies according to the type of placenta and the portion of umbilical cord insertion / 대한산부인과학회잡지

OBJECTIVE: To investigate the effect of the type of placenta and the portion of umbilical cord insertion on birthweight and growth discordancy in twin pregnancies. METHODS: We selected 120 twins of 146 multiple pregnancies between March, 2000 and March, 2002, and one fetus of all cases at least weighed 500 g or more and over 24 weeks of gestation. The fetuses were included that 44 twins (88 fetuses) had monochorionic placentas and the 76 twins (152 fetuses) had dichorionic placentas. The dichorionic twins were divided into two groups; one (38 twins, 76 fetuses) showed the fused type of placenta and the other (38 twins, 76 fetuses) showed the separate type of placenta. The types of umbilical cord insertion were also divided into the central portion and the peripheral portion, the peripheral portion was defined within 2 cm of margin of placenta, and included marginal and velamentous insertion of umbilical cord. Stastical analysis were performed with Student t-test and runs test. p<0.05 was defined significantly. RESULTS: 1. The central type of umbilical cord insertion in dichorionic placenta was more frequent than that of monochorionic placenta (p<0.01). 2. The dichorionic infants, regardless the number of placenta, who weighed more than monochorionic infants at birth (p<0.01). 3. Twin pairs with over 25% of growth discordancy were 16 cases (13.3%), which included 9 cases (9/76, 11.8%) of dichorionic placenta and 7 cases (7/44, 15.9%) of monochorionic placenta. The severe growth discordancy was more commonly developed in monochorionic twins than dichorionic twins (p<0.01). 4. Perinatal deaths in twin pairs with over 25% of GD were 12 cases, which included 3 cases (3/18, 16.7%) of dichorions, and 9 cases (9/14, 64.3%) of monochorions. Therefore, perinatal death was showed more commonly in monochorinic twin infants (p<0.01). CONCLUSION: The type of umbilical cord insertion affected the birthweight of dichorionic separated infants. Monochorionic placenta attributed to more severe growth discordancy and increased perinatal death rate than the dichorionic placenta. Antenatal detection of chorionicity and the portion of umbilical cord insertion may improve the perinatal outcome.