Daily changes in amniotic and allantoic fluid during the last three months of pregnancy in conscious, unstressed ewes, with catheters in their foetal fluid sacs

1. Catheters were inserted into the maternal and foetal vasculatures of ten ewes, 100-139 days pregnant, and daily samples of uterine and umbilical blood and maternal jugular vein blood were taken for periods of 5-27 days after operation.

2. Catheters were inserted into the fluid sacs of nineteen foetuses, 60-97 days post-conception, and daily samples were withdrawn for up to 90 days from amniotic sacs (eleven foetuses) and for up to 70 days from allantoic sacs (eight foetuses). Maternal jugular plasma was obtained 3 times weekly and an approximation from its composition to that of uterine and umbilical plasma was made using results from the ewes and foetuses with vascular catheters.

3. The pH, osmolality, [Na⁺], [K⁺], [Cl^-], [urea] and [amino acid] of all samples were measured.

4. The nutritional status of all ewes was monitored throughout pregnancy. Most lambs were born naturally at ~ 147 days post-conception and their subsequent progress was observed.

5. Results at operation and from acute experiments were compared with those from conscious ewes and foetuses of the same gestational age to assess the nature and extent of the influence of the operative procedures on foetal fluid composition. The composition of amniotic fluid was influenced mainly by the anaesthetic and surgical procedures while that of allantoic fluid was affected largely by starvation of the ewe.

6. Changes during recovery from operation were followed and indicated that maternal and foetal plasma required about 3 days and the foetal fluids up to 7 days before stability of composition was achieved.

7. After recovery from operation, daily changes in the composition of each foetal fluid showed the same general pattern in all foetuses, but the absolute values of constituents sometimes showed large differences.

8. It is suggested that flow of foetal urine into the amniotic sac increased from 80 days gestational age, that urine flow into the allantoic sac decreased until about 100 days but did not cease thereafter, and that relative to foetal urine the influence of foetal pulmonary fluid on amniotic fluid composition was not great.

9. A relative impermeability of the amnion appeared to be a major factor influencing amniotic fluid composition, whereas pumping mechanisms in the chorioallantois seem to have been responsible largely for changes in the composition of allantoic fluid.

10. The quantity of solute relative to that of water within each sac appears to be a major determinant of changes in foetal fluid volumes.

11. Changes in the [Na⁺] and [K⁺] of allantoic fluid during the normal course of pregnancy were consistent with an increasing action of mineralo-corticoids on pumping mechanisms in the chorioallantois. Similar but more rapid changes seemed to be associated with acute and chronic episodes of maternal hypoglycaemia. Under these circumstances foetal hypoglycaemia may effect a relative increase in the secretion of foetal corticosteroids having an action on the chorioallantois.

12. The results from this study demonstrate clearly the value of using chronically catheterized animals, and it is suggested that their use in physiological studies on the conceptus must eventually supersede that of acute, anaesthetized preparations.

     

The composition of maternal plasma and foetal urine after feeding and drinking in chronically catheterized ewes during the last two months of pregnancy

1. The fluid sacs and bladders of sixteen foetuses in fourteen ewes were catheterized between 81 and 92 days gestational age and the rumens of four ewes were also catheterized.2. Between 95 and 145 days gestational age in forty-six 24 hr experiments hourly samples of maternal plasma and foetal urine were obtained and in fifteen experiments foetal fluid samples were also taken at 4- to 6-hr intervals.3. The osmolality, pH, and concentrations of sodium, potassium, chloride, glucose, fructose and urea were measured on all samples.4. During experiment there was no significant variation in the composition of amniotic or allantoic fluid. Marked changes in osmolality occurred in maternal plasma and foetal urine when ewes drank after feeding, but not in ewes that received water intrarumenally via catheter while feeding or in fasting ewes. Post-prandial changes in maternal plasma osmolality may have altered transplacental water fluxes and as a result foetal plasma volume and osmolality.5. The results suggest that the foetus alters renal water retention by varying antidiuretic hormone (ADH) secretion in response to changes in blood volume and at later gestational ages plasma osmolality as well.6. Post-prandial changes in the [Na(+)]/[K(+)] ratio of foetal urine suggested that foetal adrenocorticotrophin (ACTH) secretion is influenced by variations in foetal blood volume and glucose concentrations.7. The post-prandial changes in foetal urine composition observed here support previous suggestions (Mellor & Slater, 1972) about the role of foetal urine in foetal fluid formation which were based on gestational changes in the composition of foetal fluids and urine sampled once daily during the post-absorptive state.     

Daily changes in foetal and maternal blood of conscious pregnant ewes, with catheters in umbilical and uterine vessels

1. Blood gas tensions, pH, packed cell volume (PCV) and the levels of glucose, fructose and lactic acid have been followed in foetal and maternal blood for periods of 3-30 days in conscious ewes between 80 days gestation and term ( approximately 147 days).2. Blood samples were withdrawn through indwelling catheters placed in one or both umbilical vessels, a uterine vein and a maternal artery.3. The success of the operation appeared to depend on the maintenance of maternal blood gas and pH levels within normal limits as well as on the final position of the tip of the catheter. The difficulties and limitations of the technique are discussed.4. Foetal blood gas tensions, pH, PCV, lactic acid and glucose levels did not change markedly during the last 50-60 days of gestation. The fructose concentration fell during this period, the greatest change was between 100 and 120 days gestation.5. Small fluctuations in P(O2), P(CO2) and pH in umbilical venous blood were associated with similar changes in the uterine vein, so that the gradients across the placenta appeared to remain constant.6. Daily changes in maternal plasma glucose levels were reflected in similar changes in foetal plasma fructose and by much smaller alterations in the foetal glucose levels. The glucose concentration in the foetal plasma was less than 25% of that in maternal plasma.7. The existence of a general relationship between maternal plasma glucose and foetal plasma fructose was masked by the independent fall in fructose levels with age. However, at any given stage of gestation, there was a significant correlation between foetal fructose and maternal glucose.8. Few changes in the umbilical blood were associated with impending abortion or birth. Blood gas tensions remained constant, but a sharp fall in fructose levels often occurred 48 hr before any changes in pH, PCV and lactate concentration.9. Present and other findings on conscious animals are compared with previous observations on acute, anaesthetized preparations.     

Alterations in polyamine levels in amniotic fluid, plasma and urine during normal pregnancy

Polyamines have a close relationship with rapid cell proliferation. We measured polyamine levels in amniotic fluid, maternal plasma and urine during normal pregnancy. Plasma putrescine, spermidine and spermine gradually increased in the third trimester and reached the highest concentration at the end of pregnancy. There was a significant correlation between the level of these polyamines and the level of plasma estradiol and progesterone. In urine, putrescine and spermine increased with the progress of gestation and reached the highest level during the 8th to 10th months of gestation. In amniotic fluid, putrescine and spermidine concentrations were significantly high in the first trimester and decreased in the other trimesters, whereas spermine showed no significant change. Polyamine concentrations in maternal plasma and urine appear to reflect not only fetal metabolic changes but also the metabolic changes of the pregnant women, and to be influenced by several hormones which increase during pregnancy. Polyamines in amniotic fluid mainly reflect activated fetal metabolism and may be useful as biochemical indicators of fetal growth.     

Daily changes in the blood composition of conscious pigs with catheters in foetal and uterine vessels during late gestation

1. Catheters were inserted into the foetal carotid artery and maternal middle uterine artery and vein in twenty foetuses from fifteen sows, 91-105 days pregnant. Blood samples were collected from foetal and maternal circulations for periods of 7-21 days after surgery.2. Blood gas tensions, pH, packed cell volume (PCV) and the levels of glucose, fructose and lactic acid in conscious pigs were followed in foetal and maternal bloods during late pregnancy.3. Foetal blood gas tensions, pH, PCV, lactic acid and glucose levels did not change markedly during the last 20-25 days of gestation. Blood fructose concentration fell during this period with the greatest change occurring after 100 days gestation. Foetal and maternal blood pH values were higher than those reported in the sheep, cow, mare and rhesus monkey.4. Small changes in P(CO2) and pH in foetal carotid blood were associated with similar changes in maternal uterine venous blood, so that gradients between sow and foetus remained relatively constant.5. Daily changes in maternal blood glucose levels were associated with smaller changes in foetal blood glucose and fructose levels. Blood glucose concentrations in foetal blood were generally 40-70% of maternal concentrations. Over-all relationships between maternal blood glucose and foetal blood fructose concentrations were masked by the independent fall in foetal fructose levels with age.6. The present findings have been compared with previous observations on acute, anaesthetized preparations in pigs, and chronic preparations in other domestic animals.     

Gamma-glutamyl transferase activity in fetal serum, maternal serum, and amniotic fluid during gestation.

Gamma-glutamyl transferase activity was measured in fetal serum, maternal serum, and amniotic fluid in 173 pregnancies from 15 to 40 weeks' gestation. Fetal serum was obtained in the second trimester by fetoscopy and in the third trimester by umbilical cord puncture at caesarian section or vaginal delivery. Enzyme activities in maternal blood (10 IU/1, SD 2) and fetal blood (88 IU/1, SD 20) remained relatively constant throughout gestation, whereas in the amniotic fluid there was a significant decrease at term from the value in the second trimester (p less than 0.001). Electrophoretic separation of the enzyme showed one isoenzyme in the fetal blood and at least two in the amniotic fluid. The fetal isoenzyme had the same mobility as the major isoenzyme in the amniotic fluid.     

Influence of time of infection during pregnancy with coxsackievirus B3 on maternal pathology and foetal growth in mice.

Coxsackievirus B3 causes foetal wastage and growth retardation in mice which may be attributed to the action of the virus in destroying the maternal exocrine pancreas. Injection of virus on Day 4 or 8 of gestation caused greater foetal wastage than injection at 12 days. Foetal and placental weights in infected animals were less than in the controls but did not vary according to the time of infection. Little support is offered for the view that the mouse foetus differs in its susceptibility to Coxsackievirus B3 according to the stage in gestation of infection.     

Determination of 3'-azido-2',3'-dideoxyuridine in maternal plasma, amniotic fluid, fetal and placental tissues by high-performance liquid chromatography

3'-Azido-2',3'-dideoxyuridine (AZDU, Azddu, CS-87) is a nucleoside analog of 3'-azido-3'-deoxythymidine (zidovudine, AZT) that has been shown to inhibit human immunodeficiency virus (HIV-1). AZDU is a potential candidate for treatment of pregnant mothers to prevent prenatal transmission of HIV/AIDS to their unborn children. A rapid and efficient high-performance liquid chromatography (HPLC) method for the determination of AZDU concentrations in rat maternal plasma, amniotic fluid, placental and fetal tissue samples has been developed and validated. Tissue samples were homogenized in distilled water, protein precipitated and extracted using a C-18 solid-phase extraction (SPE) method prior to analysis. Plasma and amniotic fluid samples were protein precipitated with 2 M perchloric acid prior to analysis. Baseline resolution was achieved using a 4.5% acetonitrile in 40 mM sodium acetate (pH 7) buffer mobile phase for amniotic fluid, placenta and fetus samples and with a 5.5% acetonitrile in buffer solution for plasma at flow-rates of 2.0 ml/min. The HPLC system consists of a Hypersil ODS column (150x4.6 mm) with a Nova-Pak C-18 guard column with detection at 263 nm. The method yields retention times of 6.2 and 12.2 min for AZDU and AZT in plasma and 8.3 and 17.6 min for AZDU and AZT in amniotic fluid, fetal and placental tissues. Limits of detection ranged from 0.01 to 0.075 microg/ml. Recoveries ranged from 81 to 96% for AZDU and from 82 to 96% for AZT in the different matrices. Intra-day (n=6) and inter-day (n=9) precision (% RSD) and accuracy (% Error) ranged from 1.48 to 6.25% and from 0.50 to 10.07%, respectively.     

Physiological leukocytosis during pregnancy is associated with changes in glucose transporter expression of maternal peripheral blood granulocytes and monocytes

PROBLEM: The scarce data on glucose transporter expression of leukocytes are contradictory and nothing is known about changes accompanying physiological leukocytosis during pregnancy, which imposes acute metabolic demands on the cells. METHOD OF STUDY: Cytospin preparations of intravascular leukocytes were searched immunocytochemically for the high affinity glucose transporters GLUT1, 3 and 4. Pregnancy-associated quantitative changes in transporter expression were assessed by flow cytometry. RESULTS: Granulocytes and monocytes stained for GLUT1, 3 and 4. Major changes in cell surface transporter expression during pregnancy were a 36% (P < 0.05) down-regulation of granulocyte GLUT1 at term, and an increase in monocyte GLUT3 levels to 137% (P < 0.05), paralleled by a 24% (P < 0.05) decrease in GLUT4 content in second trimester. Apart from a minor subpopulation, lymphocytes were negative for these carriers. CONCLUSION: GLUT1, 3 and 4 are abundantly expressed in granulocytes and monocytes. The particular isoforms are differentially regulated during pregnancy, suggesting an individual functional significance.     

Bone density changes during two years treatment with tibolone or conjugated estrogens and norgestrel, compared with untreated controls in postmenopausal women

OBJECTIVE: To quantify and compare the effect of two different hormone replacement therapy regimens on bone mineral density (BMD) and serum alkaline phosphate levels against a group of no treatment control volunteers. METHODS: An open 104-week comparative study of 113 early postmenopausal women. Fifty volunteered for the no treatment arm; the remainder were randomized to tibolone (T) (n = 32) or conjugated estrogens plus sequential norgestrel (CEEP) (n = 31). BMD was measured at baseline and after 48 and 96 weeks by dual photon absorptiometry. RESULTS: Baseline BMD was lower in nontherapy controls and with women assigned to CEEP compared with the T group. Statistical significance was not reached. By 96 weeks, increased BMD was observed with both therapies at all sites, whereas controls had lost bone compared with baseline. Changes from baseline with both preparations were significantly different (p < 0.05) from changes in controls for all sites, except femoral neck where the change was significant only with CEEP (p < 0.05). Alkaline phosphatase was significantly reduced in both treatment groups compared with controls (p < 0.05) at 48 and 96 weeks. CONCLUSIONS: The significant increases in BMD with T and CEEP confirm both regimens are effective in preventing osteoporosis. Without treatment, BMD declines postmenopausally.     

Changes in serum concentrations and pituitary content of the two prolactins and growth hormone during the reproductive cycle in female tilapia, Oreochromis mossambicus, compared with changes during fasting

Patterns of change in serum concentrations and pituitary content of GH and two tilapia prolactins (PRL177 and PRL188) were examined during the reproductive cycle of female tilapia, Oreochromis mossambicus, adapted to fresh water and to seawater. Changes in these hormones during fasting were examined to elucidate whether changes observed during brooding could be attributed to a reduction in feeding during brooding. Serum concentrations of GH increased prior to pituitary content during the brooding phase of the reproductive cycle. In contrast, pituitary content of GH increased prior to serum concentrations during fasting. There was no consistent pattern of change in serum or pituitary PRL levels during the reproductive cycle, among experiments. Serum concentrations of PRL177 were elevated in all fasted fish, whereas PRL188 was elevated during fasting in males but not females. The increases in the serum concentration of PRLs and GH, and in the pituitary content of GH in response to fasting support the notion that these hormones are involved in the regulation of the use of metabolic substrates in tilapia. We conclude that reduced food intake during brooding may contribute to changes in serum and pituitary levels of the PRLs and GH observed during the reproductive cycle. Nevertheless, differences between changes in serum and pituitary GH during brooding and fasting suggest GH has actions in reproduction, and changes in GH during brooding are not only in response to fasting.     

Height, weight, and motor-social development during the first 18 months of life in 126 infants born to 109 mothers with polycystic ovary syndrome who conceived on and continued metformin through pregnancy

BACKGROUND: We prospectively assessed growth and motor-social development during the first 18 months of life in 126 live births (122 pregnancies) to 109 women with polycystic ovary syndrome (PCOS) who conceived on and continued metformin (1.5-2.55 g/day) through pregnancy. METHODS: The lengths and weights of PCOS neonates were compared with gender-specific Centers for Disease Control and Prevention (CDC) infant data. Gestational diabetes (GD) and pre-eclampsia in women with PCOS were compared with 252 healthy women without PCOS who had >or=1 live birth (262 live births). RESULTS: There were 101 out of 126 (80%) term (>or=37 gestational weeks) PCOS births, which was not significantly different (P = 0.7) from controls, 206 out of 252 (81.7%). There were two (1.6%) birth defects. GD occurred in nine out of 119 PCOS pregnancies (7.6%) versus 40 out of 251 (15.9%) controls, P = 0.027. The prevalence of pre-eclampsia did not differ in PCOS versus control pregnancies (4.1 versus 3.6%, P = 0.8). The birth length and weight of the 52 male neonates did not differ (P > 0.05) from those of CDC males; the 74 female neonates were shorter than CDC females (48.9 +/- 5.4 versus 50.6 +/- 2.7 cm, P = 0.006) and weighed less (3.09 +/- 0.85 versus 3.29 +/- 0.52 kg, P = 0.04). There were no systematic differences in growth between PCOS and CDC infants over 18 months. At 3, 6, 9, 12 and 18 months, of a potential 100% motor-social development score, scores (+/-SD) were 95 +/- 13, 98 +/- 8%, 95 +/- 10, 97 +/- 8 and 94 +/- 16%; no infants had motor-social developmental delays. CONCLUSIONS: Metformin reduced development of GD, was not teratogenic and did not adversely affect birth length and weight, growth or motor-social development in the first 18 months of life.     

Polyunsaturated fatty acid levels in blood during pregnancy, at birth and at 7 years: their associations with two common FADS2 polymorphisms

Minor alleles of polymorphisms in the fatty acid desaturase (FADS) gene cluster have been associated with reduced desaturation of the precursor polyunsaturated fatty acids (FAs) in small studies. The effects of these polymorphisms during progressive developmental stages have not previously been reported. Data from blood samples for 4342 pregnant women, 3343 umbilical cords reflecting the newborn's blood supply and 5240 children aged 7 years were analysed to investigate the associations of polyunsaturated FAs with rs1535 and rs174575-two polymorphisms in the FADS2 gene. Strong positive associations were observed between the minor G allele for these two markers, especially rs1535, and the substrates linoleic (18:2n-6) and α-linolenic (18:3n-3) acid. Negative associations were observed for the more highly unsaturated FAs such as arachidonic acid (20:4n-6), timnodonic acid (EPA, 20:5n-3) and cervonic acid (DHA, 22:6n-3). Bivariable genetic associations using the mother and child genotypes suggested that the newborn metabolism had a greater capacity to synthesize the more highly unsaturated omega-6 FAs than the more highly unsaturated omega-3 FAs. Nevertheless, despite the immaturity of the neonate, there was evidence that synthesis of DHA was occurring. However, by 7 years, no associations were observed with the maternal genotype. This suggested that the children's FA levels were related only to their own metabolism with no apparent lasting influences of the in utero environment.     

A Japanese version of Mother-to-Infant Bonding Scale: factor structure, longitudinal changes and links with maternal mood during the early postnatal period in Japanese mothers

The objectives of this study were (1) to develop a Japanese version of Mother-to- Infant Bonding Scale Japanese version (MIBS-J) based on Kumar's Mother Infant Bonding Questionnaire that could be used to screen the general population for problems in the mother's feelings towards her new baby and to validate it for clinical use and (2) to examine the factor structure of the items and create subscales of the questionnaire for the Japanese version. The MIBS-J is a simple self-report questionnaire designed to detect the problems in a mother's feelings towards her newborn baby. Participants (n?=?554) were recruited at an outpatient clinic of a maternity hospital in a community after 30-weeks gestation. MIBS-J and the Edinburgh Postnatal Depression Scale (EPDS) were administered on the fifth day at the maternity ward and mailed at 1 and 4?months postnatally. Exploratory factor analysis and confirmatory factor analysis demonstrated a two-factor structure out of eight items: lack of affection (LA) and anger/rejection (AR). Chronbach's α coefficients were 0.71 and 0.57, respectively. The LA and AR scores had strong correlations across postnatal times. The mothers with higher (worse) AR scores on the MIBS-J at any of the three periods had higher scores on the EPDS. MIBS-J demonstrated acceptable reliability and reasonable construct validity in this Japanese sample.