Comparison of fetal growth in singleton, twin, and triplet pregnancies.

The objective of this longitudinal retrospective study was to evaluate differences of the fetal growth and fetal organ growth among singleton small for gestational age (S-SGA), singleton appropriate for gestational age (S-AGA), twin (Tw-AGA), and triplet (Tri-AGA) infants. Ultrasonographic examinations were performed on 35 S-AGA, 18 S-SGA, 52 Tw-AGA and 12 Tri-AGA fetuses. Circumferences of head (HC), abdomen (AC), spleen (SC) and adrenal gland (AGC) and lengths of femur diaphysis (FDL), liver (LL), estimated weight (EWT) were measured every 2 weeks after 15 weeks of menstrual age until delivery. There was no significant difference in predicted HC values in S-AGA, Tw-AGA and Tri-AGA fetuses; these values were lowest in S-SGA fetuses. As the number of fetuses in the uterus increased with advancing menstrual age, the slope of the growth curve for predicted AC value became lower, but there was no significant difference between Tri-AGA and S-SGA fetuses. There was no significant difference in predicted FDL values among Tw-AGA, Tri-AGA and S-SGA fetuses; those values were significantly lower than that in S-AGA fetuses. There was no significant difference in predicted EWT value between Tw-AGA and Tri-AGA fetuses, which were intermediate between those for S-AGA and S-SGA fetuses. There were no significant differences in predicted SC and AGC values between S-AGA and Tw-AGA fetuses, respectively. However, in S-SGA fetuses, the slopes of the growth curve for SC and AGC were lower than those in the other two groups with advancing menstrual age. There were slight differences in predicted LL values between S-AGA, S-SGA and Tw-AGA fetuses. These results suggest that in AGA fetuses, there was a slight difference in growth pattern among singleton, twin, and triplet pregnancies.     

Distribution of fetal erythroblasts enriched from maternal blood in multifetal pregnancies

BACKGROUND: The aim of this study was to establish the frequency of fetal cells in the maternal blood of multifetal pregnancies and compare this figure with singleton pregnancies. METHODS: We obtained maternal blood from 31 pregnancies with 2-6 fetuses at 11-16 weeks gestation and from 50 normal singleton controls (11-14 weeks gestation). Fetal erythroblasts were isolated from maternal blood using triple density gradient separation and anti-CD71 magnetic cell-sorting techniques. The enriched erythroblasts were stained with Kleihauer-Giemsa and with fluorescent antibodies for the zeta (zeta), epsilon (epsilon) and gamma (gamma) globin chains. The percentage of fetal cells positive for each stain was calculated. Fluorescence in-situ hybridization (FISH) for X and Y chromosomes was also performed. RESULTS: The percentage of erythroblasts enriched from maternal blood that stained positive for zeta, epsilon and gamma globin chains and with Kleihauer-Giemsa was significantly higher in the multifetal compared with singleton pregnancies. The median enriched percentage of positively stained erythroblasts was about three times higher in the twin than in singleton pregnancies (P < 0.0001), nearly twice as high in the triplet than in twin pregnancies (P < 0.01) and five times higher in the triplet than singleton pregnancies (P < 0.0001). FISH for Y chromosome confirmed the increase in fetal cell proportion in the multifetal pregnancies. CONCLUSIONS: These findings suggest that there is an increase in the physiological feto-maternal cell trafficking in multifetal pregnancies compared with singleton pregnancies, which is likely to be due to the increased placental surface area and vasculature.     

Maternal ophthalmic artery doppler velocimetry in type 1 diabetes during pregnancy

Our purpose was to evaluate whether maternal ophthalmic artery pulsatility index (PI) in normotensive pregnancies with type 1 diabetes is different from that in normal normotensive pregnancies. The ophthalmic artery in 15 normal normotensive pregnant women, and 13 normotensive pregnant women with type 1 diabetes was studied once with colour Doppler flow imaging and pulsed Doppler ultrasonography after 16 weeks gestation. The heart rate, mean arterial blood pressure, and ophthalmic artery PI were calculated in each group. The PI (1.94 +/- 0.45) in normotensive pregnant women with type 1 diabetes was significantly lower than that (2.73 +/- 0.32) in normal normotensive pregnant women (P < 0.0001). There was no significant difference in maternal heart rate or mean arterial blood pressure between the two groups. These results suggest that vascular resistance in the maternal orbital circulation is reduced in pregnancies with type 1 diabetes that are normotensive. The lower PI in pregnant women with type 1 diabetes should be interpreted as orbital vascular vasodilatation, indicating orbital hyperperfusion or hyperaemia.     

Fetal heart rate and umbilico-placental Doppler flow velocity waveforms in early pregnancies with a chromosomal abnormality and/or an increased nuchal translucency thickness

Fetal heart rate, umbilical artery pulsatility index, end-diastolicflow,nuchal translucency thickness and placental thickness were recordedin 250 women with a viable singleton pregnancy undergoing chorionicvillous sampling for fetal karyotyping at 11–14 weeksof gestation. The fetal karyotype was normal in 210 cases andabnormal in 40, including 21 with trisomy 21, 13 with trisomy18, three with triploidy, two with monosomy X and one with trisomy13. A total of 52 fetuses with a normal karyotype had a nuchaltranslucency 3 mm and were considered separately. There wasa stable and significant increase in the mean fetal heart ratein trisomy 21 pregnancies compared to controls. No significantdifference was found for the other variables between the groups.In chromosomally normal fetuses with an increased nuchal thickness,the development of fetal heart rate and compliance of the umbilico-placentalcirculation were within the normal ranges. Some fetuses withtrisomy 18 or triploidy had an increased resistance to bloodflow in the umbilical artery, which was probably due to abnormalplacental development.     

Uterine artery Doppler velocimetry and the outcome of pregnancies resulting from ICSI.

BACKGROUND: An increased incidence of pregnancy complications following assisted reproduction has been reported. The use of uterine artery Doppler ultrasound may aid the prediction of such complications. METHODS: Doppler was performed at 18-24 weeks gestation in 114 singleton and 32 twin pregnancies after intracytoplasmic sperm injection (ICSI) and compared with a control group matched for age, parity and plurality. Outcome variables included gestational age at delivery, prematurity, preterm premature rupture of membrane (PPROM), birth weight, birth weight discordance of >20% in twins, small for gestational age (SGA), mode of delivery, development of pre-eclampsia and placental abruption. RESULTS: Compared with the controls, there were no significant differences concerning uterine Doppler parameters, pregnancy complications and the neonatal outcome, either in singleton or in twin pregnancies. According to Doppler results and/or risk factors by medical history, 42% of singleton ICSI and 39% of spontaneous singleton pregnancies were considered as high risk. In singletons, abnormal Doppler findings were associated with pre-eclampsia in 22% and SGA in 26% of ICSI patients, compared with 33 and 21% in controls; in contrast, 0 and 10% in ICSI and 3 and 6% in controls showed these complications but no risk factors respectively. No correlation was found between PPROM, prematurity, the rate of Caesarean section and pathological Doppler results. CONCLUSIONS: Uterine Doppler examination holds the potential to identify patients with an increased risk for developing pregnancy complications. According to our results, this risk is not elevated after ICSI treatment, therefore the decision of offering an intensified antenatal care should be based on the results of Doppler examination or risks by medical history rather than the mode of conception.     

彩色多普勒及无应激试验监测胎儿窘迫的临床应用

目的探讨彩色多普勒超声及无应激试验（NST）监测胎儿窘迫的临床价值。方法80例孕龄37-42周的孕妇,其中40例胎儿窘迫及40例胎儿正常。均于产前进行彩色多普勒超声探测及NST。结果胎儿窘迫组其血流阻力指标：胎儿大脑中动脉（MCA）的S/D、血流阻力指数（RI）、搏动指数（PI）明显低于胎儿正常组（P〈0.01）,而母体子宫动脉（UTA）的血流阻力指标均明显高于胎儿正常组（P〈0.01）。此外,胎儿窘迫组与胎儿正常组S/D与NST对胎儿缺氧检测,其灵敏度、特异度、阳性预测值、阴性预测值分别为92.5%、95.0%、94.5%、92.7%,NST为75.0%、62.5%、66.7%、71.4%。S/D对胎儿窘迫的检出率明显高于NST。结论应用彩色多普勒超声检测血流动力学中阻力指标对胎儿窘迫的诊断优于NST。     

The feto-placental unit stimulates the pregnancy-associated increase in maternal bone metabolism

The aim of the study was to investigate role of the feto-placental unit in the pregnancy-induced increase in maternal bone metabolism. To achieve this, circulating concentrations of carboxy terminal pro-peptide of type I pro-collagen (PICP, a marker of bone formation) and cross-linked carboxy terminal telopeptide of type I collagen (ICTP, a marker of bone resorption) were measured in three groups of pregnant women. Group 1 comprised 12 women with singleton pregnancies; group 2, nine women with twin pregnancies; and group 3, 19 women with multifetal pregnancies (> or =3 fetuses) before and after selective fetal reduction to twin pregnancies. Blood samples were obtained at 10-12 weeks gestation (groups 1-3, pre-fetal reduction in group 3) and 4 weeks and 8 weeks later (groups 2 and 3). Before fetal reduction there was a significant correlation between the number of fetuses and the concentrations of both PICP and ICTP (r = 0.503 and P = 0.001 and r = 0.573 and P < 0.001 respectively). The circulating concentrations of PICP and ICTP were significantly higher in the pre-reduction multifetal pregnancies than in the twin pregnancies (P < 0.001 and P = 0.0013 respectively). The circulating concentrations of ICTP in multifetal pregnancies fell by 4 weeks after fetal reduction to those observed in control twins. Concentrations of PICP were unaltered after fetal reduction. Higher order multiple pregnancies had the greatest decline in ICTP concentrations. These data suggest that the increased bone turnover observed in the multifetal pregnancies is due to a factor derived from the feto-placental unit and that this factor acts primarily to stimulate bone resorption.     

Pregnancy: The influence of the number of embryos transferred in 1060 in-vitro fertilization pregnancies on miscarriage rates and pregnancy outcome

To assess the incidence of miscarriage, multiple pregnancy andoutcome of pregnancy in relation to the number of embryos transferredduring in-vitro fertilization (IVF), an analysis was performedof 1060 pregnancies conceived in a tertiary-referral IVF clinic.There was no difference in the miscarriage rate after transferof one or two embryos (37.7% and 34.6%), or after three or fourembryos (22.5% and 25.2%). The miscarriage rate was, however,higher when one or two embryos were transferred compared withthree (P < 0.01) or four embryos (P < 0.02). Of the 724ongoing pregnancies, 524 (72.3%) were singleton, 164 (22.7%)twin, 33 (4.6%) triplet and three (0.4%) quadruplet. The mean(±SD) ages of women with singleton, twin, triplet andquadruplet pregnancies were 32.5 (±3.8), 32.0 (±3.5),29.76 (±4.3) and 29.67 (±2.5) years respectively.The mean age of women with singleton and twin pregnancies wassimilar and both were greater than that of triplet pregnancies(P < 0.007). The overall perinatal mortality rate (PNMR)was 39.7/1000. The PNMR for singletons was 17.2/1000, for twins80.0/1000 and for triplets 30.6/1000. All of the babies fromthe three quadruplet pregnancies survived. There were more babieslost in the twin pregnancies than any other group, althoughthis only reached significance for singletons versus twins (P< 0.00005). We conclude that the incidence of miscarriageis increased in women in whom one or two embryos are transferred.Multiple pregnancies are more likely to occur in younger womenand are associated with a significantly higher rate of perinatalmortality.     

Risk of spontaneous abortion in singleton and twin pregnancies after IVF/ICSI

BACKGROUND: The risk of spontaneous first trimester abortion is estimated to be between 10 and 20%. Although it is common knowledge that the incidence of abortion decreases as pregnancy progresses, exact data in relation to the duration of pregnancy are scarce. METHODS: We reviewed 1597 clinical IVF/ICSI pregnancies with known outcome and tabulated the number of miscarriages or fetal demise per intervals of 2 weeks. We furthermore compared the outcome in terms of fetal survival of 1200 singleton pregnancies with that of 397 twin pregnancies. RESULTS: The overall incidence of non-ongoing singleton pregnancies was 21.7%. Fetal death, after positive heart activity had been recorded, occurred in 12.2% of singleton pregnancies. The overall incidence of spontaneous abortion in twin pregnancies was 17.1% (12.1% vanishing twins and 5.0% complete miscarriages). The incidence of miscarriage in the twin pregnancies, expressed per gestational sac, was 11.1%. Once fetal heart activity was present, the risk of abortion (per gestational sac) was 7.3%, which is significantly lower than that in singleton pregnancies. CONCLUSIONS: Our data give an estimate of the probability of miscarriage or fetal demise at any given period of the first trimester both for singleton and twin pregnancies. Twin pregnancies after IVF have a better potential for survival than singleton pregnancies.     

Spontaneous abortion in multiple pregnancy: focus on fetal pathology

Multiple pregnancy with its wide array of medical consequences poses an important condition during pregnancy. We performed perinatal autopsy in 49 cases of spontaneous abortion resulting from multiple pregnancies during the study period. Twenty-seven of the 44 twin pregnancies ending in miscarriage were conceived naturally, whereas 17 were conceived through assisted reproductive techniques. Each of the 5 triplet pregnancies ending in miscarriage was conceived through assisted reproductive techniques. There was a positive history of miscarriage in 22.4% of the cases. Monochorial placentation occurred more commonly in multiple pregnancies terminating with miscarriage than in multiple pregnancies without miscarriage. A fetal congenital malformation was found in 8 cases. Three of these cases were conceived through assisted reproductive techniques, and 5 were conceived naturally. Miscarriage was due to intrauterine infection in 36% of the cases. Our study confirms that spontaneous abortion is more common in multiple than in singleton pregnancies. Monochorial placentation predicted a higher fetal morbidity and mortality. In pregnancies where all fetuses were of male gender, miscarriage was more common than in pregnancies where all fetuses were female. Assisted reproductive techniques do not predispose to the development of fetal malformations.     

Perinatal outcome of 12,021 singleton and 3108 twin births after non-IVF-assisted reproduction: a cohort study

Perinatal outcome of pregnancies caused by assisted reproduction technique (ART) is substantially worse when compared with pregnancies following natural conception. We investigated the possible risks of non-IVF ART on perinatal health. We conducted a retrospective cohort study with two exposure groups: a study group of pregnancies after controlled ovarian stimulation (COS), with or without artificial insemination (AI), and a naturally conceived comparison group. We used the data from the regional registry of all hospital deliveries in the Dutch-speaking part of Belgium during the period from January 1993 until December 2003 to investigate differences in perinatal outcome of singleton and twin pregnancies. 12 021 singleton and 3108 twin births could be selected. Naturally conceived subjects were matched for maternal age, parity, fetal sex and year of birth. The main outcome measures were duration of pregnancy, birth weight, perinatal morbidity and perinatal mortality. Our overall results showed a significantly higher incidence of prematurity (<32 and <37 weeks), low and very low birth weight, transfer to the neonatal intensive care unit and most neonatal morbidity parameters for COS/AI singletons. Twin pregnancies resulting from COS/AI showed an increased rate of neonatal mortality, assisted ventilation and respiratory distress syndrome. After excluding same-sex twin sets, COS/AI twin pregnancies were at increased risk for extreme prematurity and very low birth weight. In conclusion, COS/AI singleton and twin pregnancies are significantly disadvantaged compared to naturally conceived children.     

Obstetric outcome after prenatal diagnosis in pregnancies obtained after intracytoplasmic sperm injection

In this study we compared the pregnancy outcome of 576 pregnanciesafter prenatal diagnosis with that of 540 pregnancies withoutprenatal diagnosis in our micro-injection programme. Amniocentesiswas suggested for singleton pregnancies (n = 465) and chorionicvillus sampling (CVS) was proposed for twin pregnancies (n =111 pregnancies, 222 fetuses). A total of 365 patients withsingleton pregnancies and 175 patients with twin pregnancieswho did not undergo prenatal diagnosis were selected as controls.Compared with the controls, the odds ratios in the amniocentesisgroup for preterm delivery, low birthweight, very low birthweightand fetal loss were 0.97 [95% confidence interval (CI): 0.60–1.57],1.27 (95% CI: 0.78–2.06), 1.57 (95% CI: 0.53–4.66)and 0.86 (95% CI: 0.32–2.37) respectively. Compared withthe controls, the odds ratios in the CVS group for preterm delivery,low birthweight, very low birthweight and fetal loss were 0.89(95% CI: 0.61–1.30), 1.03 (95% CI: 0.74–1.45), 0.79(95% CI: 0.41–1.53) and 0.47 (95% CI: 0.17–1.30)respectively. We concluded that, in this series of intracytoplasmicsperm injection (ICSI) pregnancies, prenatal testing did notincrease the preterm-delivery, the low-birthweight, or the verylow-birthweight rates as compared with those of the controls.In the prenatal diagnosis group, the fetal loss rate was comparableto that of the control group. Larger prospective controlledstudies are needed in order to inform patients reliably aboutthe risks and the advantages of prenatal testing in ICSI pregnancies.     

Obstetrical results after embryonic reductions performed on 34 multiple pregnancies

Thirty-four women with multiple pregnancies (three or more fetuses) underwent embryonic reduction in order to reduce abortions, premature births or fetal growth-retardation by obtention of twins. Four early abortions occurred. Thirty pregnancies reached term and out of 60 fetuses, 58 infants were born alive. Fetal death in utero of one twin occurred in two pregnancies. The mean term until delivery was 36 +/- 2.8 weeks gestation and the prematurity rate was 51.7%. Of 55 neonates, 25 were underweight within the 10th percentile and 10 out of 55 neonates were underweight below the 3rd percentile. There were three deaths in the early neonatal period. The rate of perinatal mortality was 8.3%. Fifty-four children are currently healthy and one child has a mild axial hypotonia. A reduction in prematurity was observed with a gain of 2 weeks on reported data concerning triplet pregnancies. The rate of low-birth-weight infants was high, 63.5% being underweight at birth.     

Diurnal variation in uterine artery blood flow in post-menopausal women on oestrogen hormone replacement therapy.

Doppler ultrasound was used to investigate circadian variations in uterine artery blood flow in 20 post-menopausal women in the oestrogen-only phase of combined oestrogen hormone replacement therapy with cyclical oral norethisterone or dydrogesterone. All women were examined between 0800 and 0830 h and then again between 1800 and 1830 h on the same day. Mean arterial blood pressure, heart rate and a blood sample for measurement of serum oestradiol were taken at each visit. Indices of uterine artery blood flow included the pulsatility index, resistance index, peak systolic velocity and time-averaged maximum velocity. No significant differences in the mean arterial blood pressure, pulse rate and oestradiol concentrations were detected between morning and evening visits. Significant fluctuation was observed in the pulsatility index (P < 0. 001), resistance index (P < 0.001) and time-averaged maximum velocity (P < 0.01). The assessment of uterine artery blood flow in post-menopausal women should take into account the presence of circadian variations to ensure accuracy and reproducibility of Doppler investigations.     

Vascular dysfunction during pregnancy in women with polycystic ovary syndrome

BACKGROUND: An association has been proposed between polycystic ovary syndrome (PCOS) and pregnancy-induced hypertensive disorders. Ambulatory blood pressure and carotid artery elasticity were therefore prospectively investigated in matched PCOS and control pregnancies. METHODS: Twenty-two PCOS-control subject pairs with singleton pregnancies, matched for age, body mass index, parity and ethnicity, were recruited in the first trimester (T1, 11-13 weeks). Ambulatory blood pressure recording for 24 h and carotid artery ultrasound for elasticity estimation were performed in T1 and in the second (T2, 22-24 weeks) and third (T3, 32-34 weeks) trimesters. RESULTS: At nearly all time points during gestation, ambulatory systolic, diastolic and mean arterial pressures were elevated in PCOS versus control pregnancies. Carotid artery stiffness index was greater and compliance was less in PCOS pregnancies compared with controls. Differences in night-time systolic pressure and carotid artery elasticity were greatest in T3. PCOS also increased the incidence of pregnancy-induced hypertension (6 of 22 cases versus 0 of 22 in controls; P = 0.011). CONCLUSIONS: Pregnant women with PCOS have higher baseline ambulatory blood pressure and impaired arterial elasticity, suggestive of disturbed vascular adaptation to pregnancy.     

Fetal growth according to different reference ranges in twin pregnancies with placental insufficiency

The aim of this study was to compare different fetal growth curves in twin pregnancies with severe placental insufficiency. A retrospective cross-sectional analysis of 47 twin pregnancies with absent or reverse end diastolic flow in the umbilical artery of one fetus was performed. Pregnancies with major fetal abnormalities, twin-twin transfusion or three or more fetuses were not included. The estimated fetal weight zeta-scores were calculated for both fetuses (abnormal Doppler and co-twin) according to the following criteria: Hadlock, Liao and Araújo. The abdominal circumference zeta-scores were calculated according to Hadlock, Liao, Araújo, Ong and Stirrup. The mean estimates of the zeta-score values were calculated using generalized estimating equation regression analysis.The mean gestational age at inclusion was 27.4±4.7 weeks. The fetal sex and the interaction Doppler findings × criteria correlated significantly with the zeta-score values (p<0.001 for both variables). The estimated fetal weight mean zeta-scores (standard error) according to each criteria were as follows: Hadlock - abnormal Doppler: -2.98 (0.18), co-twin: -1.16 (0.15); Liao - abnormal Doppler: -2.89 (0.24), co-twin: -0.58 (0.19); and Araújo - abnormal Doppler: -3.05 (0.29), co-twin: -0.75 (0.18). Values for abdominal circumference were as follows: Hadlock - abnormal Doppler: -3.14 (0.26), co-twin: -1.13 (0.19); Liao - abnormal Doppler: -2.63 (0.27), co-twin: -0.42 (0.19); Araújo - abnormal Doppler: -2.44 (0.22), co-twin: -0.71 (0.14); Ong - abnormal Doppler: -3.36 (0.34), co-twin: -1.48 (0.23); and Stirrup AD -- -2.36 (0.14), co-twin: -1.18 (0.10).Sex- and plurality-specific charts should be used in the evaluation of fetal growth in twin pregnancies with placental insufficiency.     

A longitudinal study of maternal serum vascular endothelial growth factor in early pregnancy

Using a competitive radioimmunoassay to measure total immunoreactive vascular endothelial growth factor (VEGF), we describe for the first time longitudinal changes in serum VEGF in early pregnancy. The measurements were obtained from 26 women following the transfer of cryopreserved embryos; 18 singleton and eight twin pregnancies were identified by ultrasound at 6 weeks gestation and subsequently delivered as live births. Subjects did not have corpora lutea and exogenous hormone support was provided for the first 70 days of pregnancy. Serum VEGF increased approximately 30 days after embryo transfer and thereafter continued to rise in both singleton and twin pregnancies over a period of 20-40 days after which concentrations remained elevated. The longitudinal profile of serum VEGF concentrations was characterized by a logistic curve for singleton and twin pregnancies; the profile of VEGF concentrations in the twin pregnancies was significantly higher than in the singleton pregnancies (P < 0.0001). Profiles of the longitudinal concentrations of serum human chorionic gonadotrophin (HCG), oestradiol and progesterone were created by polynomial regression for singleton and twin pregnancies. The VEGF profiles were positively correlated with the profiles of HCG (r = 0.44, P = 0.02) and oestradiol (r = 0.36, P = 0.07) but not progesterone (r = 0.16, P = 0.42). Serum VEGF concentrations in the singleton thawed embryo pregnancies were compared with gestation- matched normal singleton pregnancies with corpora lutea. Concentrations of VEGF were significantly (P = 0.004) greater in the pregnancies with corpora lutea although this difference became less marked with advancing gestation. In addition to its important role in angiogenesis, we speculate that VEGF is involved in mechanisms which control the maternal cardiovascular adaptation to pregnancy.      

Embryo reduction in multifetal pregnancies using saline injection: comparison between the transvaginal and the transabdominal approach.

A total of 30 patients with multifetal pregnancies, all resulting from treatment with superovulatory agents or assisted reproductive techniques, underwent embryo reduction. All patients had three or more fetuses (one sextuplet, two quintuplets, seven quadruplets and 20 triplets). The procedure was carried out using intra-embryonal injection of 0.9% sodium chloride solution. Embryo reduction was carried out via the transabdominal approach in 10 patients, performed at 11-12 weeks of gestation, and via the transvaginal route in 20 other patients, at 8-10 weeks of gestation. In the transabdominal group, one patient aborted following repeated attempts at embryo reduction while the other nine gave birth to healthy newborns (eight twins and one triplet). In the transvaginal group, four pregnancies are currently ongoing (all beyond 28 weeks of gestation), 14 pregnancies resulted in a delivery of at least one live newborn (13 twins and one singleton), one patient had a late abortion at 24 weeks' gestation and another was delivered at 27 weeks' gestation due to severe pre-eclampsia. Transvaginal ultrasound-guided needle procedures are commonly practised in most in-vitro fertilization units. The employment of this route for embryo reduction, performed at an earlier gestational age and with the use of a non-toxic substance such as 0.9% saline solution, is advocated.     

Placental and ovarian hormones in anembryonic pregnancy

The circulating levels of human chorionic gonadotrophin (HCG),pregnancy-associated plasma protein-A (PAPP-A), Schwangerschaftprotein 1 (SP-1), oestradiol and progesterone were measuredin 81 pregnant patients between 4 and 11 weeks gestation, followingin-vitro fertilization and embryo transfer. The patients weredivided as follows: singleton anembryonic pregnancies, n = 22;singleton pregnancies which spontaneously aborted followingthe demonstration of fetal heart activity, n = 7; and normalsingleton pregnancies, n = 52. The levels of all substancesmeasured were significantly reduced in women with anembryoniccompared to those with singleton pregnancies which proceededto term. The serum levels of SP-1, weeks 6–8 (P < 0.01);HCG, weeks 6–8 (P < 0.05); oestradiol, weeks 5–8(P < 0.05) and progesterone, weeks 6–8 (P < 0.05),were lower in anembryonic pregnancies than in those of pregnancieswhich spontaneously aborted. These differences may be a reflectionof the fact that miscarriage, after the demonstration of fetalheart activity, represents fetal demise at a later stage inpregnancy. In anembryonic pregnancies, significant associationswere found between HCG and both oestradiol and progesteronelevels from weeks 6 and 8, suggesting that in the absence ofan embryo, HCG is the prime determinant of steroid synthesisby the corpus luteum.     

Genetics: Genetic analysis prior to selective fetal reduction in multiple pregnancy: technical aspects and clinical outcome

Multiple pregnancies resulting from ovarian stimulation areat a higher risk of carrying at least one fetus affected byMendelian or chromosomal anomalies, the incidence of which isdirectly related to the order of multiples. Genetic analysisbefore fetal reduction was offered to both high-and low-riskpregnant women carrying two or more fetuses after ovulationinduction. Chorionic villus sampling (CVS) and fetal reductionwere achieved by transabdominal needling. The use of short-termculture, the polymerase chain reaction and fresh tissue enzymaticanalyses have made it possible for genetic diagnosis to be availablein a few days. A total of 100 patients had multifetal pregnancyreduction performed by a single operator; all of them completedpregnancy and none was lost at follow-up. The total fetal lossbefore 24 weeks was 7% and no statistically significant relationshipwas found with the final number of fetuses and CVS. Perinatallosses (3.9%) were only present in the series with a final numberof two fetuses. Pregnancy duration and birthweight were significantlyhigher in singletons than in twins, but were not related toCVS. The rate of chromosomal disorders was higher (7.2%) inthe study series than in singleton pregnancies not undergoingfetal reduction. Diagnostic error due to incorrect samplingwas reported in 1.5% of cases. These data support fetal reductionas a valuable strategy to improve the outcome of multiple pregnancy.The outcome of pregnancies reduced to singletons was significantlybetter than of those reduced to twins, and was not related toCVS. Therefore, prenatal genetic diagnosis should become anintegral part of counselling on multiple pregnancy, and is stronglyrecommended when reduction to singleton pregnancy is requested.