Quadruplets
Triplets
Pregnancy Reduction, Multifetal
Quintuplets
Anticodon
Genetic Code
Morbidity and mortality of preterm twins and higher-order multiple births. (1/23)
OBJECTIVE: To determine if preterm infants of higher-order multiple (HOM) gestations have a significantly worse outcome during hospital stay when compared with preterm twins. STUDY DESIGN: Retrospective cohort analysis. METHODS: Perinatal outcome variables including gestational age (GA), birthweight, prenatal steroid use, cesarean section delivery rate, Apgar scores, and growth retardation were analyzed for 106 preterm HOM births (triplets and quadruplets) versus 328 preterm twins admitted to a single tertiary level neonatal intensive care unit. A comparison of the mortality and major neonatal morbidities such as respiratory distress syndrome, patent ductus arteriosus, intraventricular hemorrhage, necrotizing enterocolitis, bronchopulmonary dysplasia, and retinopathy of prematurity was made for these two groups. In addition, the duration of respiratory support including surfactant therapy, nasal continuous positive airway pressure, and mechanical ventilation, as well as the length of hospitalization, was analyzed. RESULTS: There were no significant differences in major morbidities between the infants of HOM and twin births of similar GA. There was no statistically significant difference in mortality, but the data showed a trend for lesser mortality in HOM. There was a highly significant increase in antenatal steroid use as well as the use of cesarean section for delivery in the HOM when compared with twin gestations. The infants of HOM gestations were of significantly lower birthweight than the twins and had a longer hospitalization. CONCLUSION: Although premature infants of HOM had lower birthweight and needed a longer hospital stay, their mortality and morbidity at hospital discharge were not worse than that for preterm twins. (+info)Concurrent IVF and spontaneous conception resulting in a quadruplet pregnancy. (2/23)
Blastocyst transfer of just one or two embryos has been used to help limit the number of high-order gestations. In this case report we describe the occurrence of a quadruplet pregnancy after the transfer of only two blastocysts during IVF. Sonographic examination showed four fetuses and what appeared to be quadriamniotic/quadrichorionic sacs, suggesting that a concomitant spontaneous conception had occurred. Definite confirmation of zygosity was obtained by genetic testing using DNA microsatellite polymorphism determinations after the birth of one boy and three girls at 32 weeks gestation. Although this event has not been reported previously, the possibility of its occurrence should be kept in mind. IVF patients with patent Fallopian tubes should be cautioned against intercourse late in their controlled ovarian stimulation, especially if they would decline multifetal reduction. (+info)Assisted reproductive technology in Europe, 1998. Results generated from European registers by ESHRE. European Society of Human Reproduction and Embryology. (3/23)
European results of assisted reproductive techniques from treatments initiated during 1998 are presented in this second ESHRE report. Data was collected from 18 European countries usually from pre-existing national registers. A total of 521 clinics from these 18 countries reported 232 443 cycles: IVF 103 919 intracytoplasmic sperm injection (ICSI) 89 192 unclassified fertilization method 667 frozen embryo replacement (FER) 34 03 oocyte donations (OD) 4629. In nine countries where all clinics reported to the register a total of 128 801 cycles were performed in a population of 165 million corresponding to 781 cycles per million inhabitants 3.2 cycles per 1000 women aged 15-49 years. After IVF ICSI the distribution of transfer of 1, 2, 3 > or =4 embryos was 11.5, 37.2, 42.0 and 9.4% respectively. Huge differences existed between countries. For IVF the clinical pregnancy rate per aspiration per transfer was 23.2% 27.0% respectively. For ICSI the corresponding rates were 24.8% 26.8%. The distribution of singleton, twin, triplet, quadruplet deliveries for IVF and ICSI combined was 73.7, 23.9, 2.3 and 0.1%. This gives a total multiple delivery rate of 26.3%. The range of triplet deliveries after IVF and ICSI differed from 0.2-5.3% between countries. Compared with 1997, the number of reported cycles has increased by 14% and the number of reporting clinics by 8%. The clinical pregnancy rate per transfer increased from 26.1 to 27.0% after IVF and from 26.4 to 26.8% after ICSI. Multiple deliveries after IVF and ICSI decreased from 29.6 to 26.3%. (+info)Assisted reproductive technology in Europe, 1999. Results generated from European registers by ESHRE. (4/23)
European results of assisted reproductive techniques from treatments initiated during 1999, are presented in this third report. Data were collected mainly from pre-existing national registers. From 22 countries 538 clinics reported 258 460 cycles: IVF 125 370, ICSI 95 221, frozen embryo replacement (FER) 34 002 and oocyte donations (OD) 3867. In eight countries, where all clinics reported to the register, a total of 99 629 cycles was performed in a population of nearly 106 million, corresponding to 943 cycles per million inhabitants and 3.9 cycles per 1000 women aged 15-49 years. After IVF and ICSI the distribution of transfer of 1, 2, 3 and >or=4 or more embryos was 11.9, 39.2, 39.6 and 9.3% respectively. Huge differences existed between countries. For IVF the clinical pregnancy rate per aspiration and per transfer was 24.2 and 27.7% respectively. For ICSI the corresponding rates were 26.1 and 27.9%. These figures represent relative increases by 2.2 to 5.2% compared with 1998. The distribution of singleton, twin, triplet and quadruplet deliveries for IVF and ICSI combined was 73.7, 24.0, 2.2 and 0.1%. This gives a total multiple delivery rate of 26.3%. Triplet deliveries after IVF and ICSI ranged from 0.3-7.0% between countries. Compared with 1998, the number of reported cycles increased by 11% and the clinical pregnancy rate per transfer increased from 27.0 to 27.7% after IVF and from 26.8 to 27.9% after ICSI. Multiple deliveries after IVF and ICSI remained unchanged at 26.3% in 1999. (+info)Quadruplet pregnancy following transfer of two embryos: Case report. (5/23)
Following a long period of secondary unexplained infertility, a couple had assisted conception treatment with IVF and transfer of two embryos 2 days later. The woman conceived and was found to have a quadruplet pregnancy. Following spontaneous labour onset at 34 weeks gestation, she was delivered by immediate Caesarean section. All four babies (three boys, one girl) were eventually discharged home with the mother. All the boys were found to be of differing zygosity. The quadruplet pregnancy was attributed to natural conception following intercourse and fertilization of oocytes not collected at the time of IVF. The wisdom of intercourse during a cycle of IVF is discussed. (+info)Monozygotic twin delivery following reduction from quadramniotic-dichorionic gestation established after ICSI and embryo transfer: Case report. (6/23)
We report the delivery of healthy monozygous (MZ) twins in a 31 year-old nulligravida following gonadotrophin ovulation induction, ICSI, assisted hatching and fresh embryo transfer. Although a sonogram on day 35 confirmed that two of four transferred embryos had implanted, a second transvaginal sonogram 1 week later showed each gestational sac had two conceptuses-all four were associated with distinct amniotic compartments. Cardiac activity was observed in all four embryos. At 12 weeks and 5 days gestation, chorionic villus sampling was performed on fetuses 1 and 2 which were euploid for chromosomes 13, 18, 21, X and Y via fluorescence in-situ hybridization analysis. Subsequent KCl injection into sacs 3 and 4 resulted in asystole for these fetuses, while cardiac activity in sacs 1 and 2 remained unchanged after reduction. A twin vaginal delivery occurred at 36 weeks gestation, resulting in the birth of two male infants and one placenta. This case represents the first known report of human quadruplet pregnancy consisting of two MZ twin sets conceived by assisted reproductive techniques. Our report reviews proposed mechanisms for explaining twinning, with special emphasis on zona pellucida micromanipulation and subsequent MZ twin induction. (+info)Survival rates during the first trimester of multiple gestations achieved by ICSI: a report of 1448 consecutive multiples. (7/23)
BACKGROUND: The purpose of this study was to determine the rate of spontaneous gestational sac loss during the first trimester in women achieving multiple pregnancies by ICSI. METHODS: A retrospective analysis was performed of 1448 consecutive multiple pregnancies conceived by ICSI. RESULTS: Of the cohort of 1448 pregnancies, twin gestations constituted 59.6% (864), triplets 30.2% (438) and quadruplets 10.0% (146). During the first trimester, 69 (4.7%) patients miscarried, while 179 (12.3%) continued their pregnancies and had fewer gestational sacs at the end of the first trimester than at the beginning. The overall loss rate of any gestational sac during the first trimester in these multiple pregnancies was 10.1%. There was a significant difference in the frequency of spontaneous reduction to twin or singleton pregnancies in the first trimester between women carrying triplets (11.7%) and those carrying quadruplets (3.5%) [P = 0.004; odds ratio (OR) 3.5; 95% confidence interval (CI) 1.3-9.1]. The frequency of gestational sac loss was significantly greater among women >35 years old (20.9%) than in women less than 35 years old (15.9%) (P = 0.03; OR 1.4; 95% CI 1.0-1.9). CONCLUSION: In multiple pregnancies there is a significant risk of spontaneous loss of any embryo during the first trimester. These findings should be considered prior to any decision about selective embryo reduction. (+info)A note on linkage analysis with affected sib triplets. (8/23)
Previously, it has been shown for affected sib pairs that the mean test is the uniformly (in theta) most powerful test in case of a multiplicative mode of inheritance and that the mean test is equivalent to parametric linkage analysis calculated under an assumed multiplicative mode of inheritance. Here, these two results are extended to samples consisting of affected sib triplets. For affected sib quadruplets, however, it is shown that these results are no longer valid. (+info)Quadruplets are defined in medicine as a type of multiple birth where four offspring are produced from the same pregnancy. This occurs when a single fertilized egg divides into four embryos, or more rarely, when four separate eggs are each fertilized by different sperm. Quadruplets face higher risks of preterm birth and other complications compared to singleton pregnancies.
Quadruplet pregnancy refers to a multiple pregnancy involving four fetuses. It is a less common form of multiple gestation, following twin and triplet pregnancies. Quadruplet pregnancies can be either monozygotic (identical) or dizygotic (fraternal). Monozygotic quadruplets occur when a single fertilized egg divides into four separate embryos, while dizygotic quadruplets result from the fertilization of four individual eggs by separate sperm cells.
Quadruplet pregnancies pose significant risks to both the mother and the fetuses compared to singleton or even twin pregnancies. These risks include preterm labor, low birth weight, gestational diabetes, preeclampsia, and other pregnancy-related complications. Due to these increased risks, medical professionals closely monitor quadruplet pregnancies and may recommend interventions such as bed rest, progesterone supplementation, or even cesarean delivery to ensure the best possible outcomes for both the mother and her four babies.
In medical terms, triplets are a type of multiple pregnancy, where three offsprings (fetuses) develop simultaneously in the uterus of a single pregnant woman. This occurs when a woman releases more than one egg during ovulation, and all three eggs get fertilized by separate sperm cells. Triplets can also occur through the use of assisted reproductive technologies such as in vitro fertilization (IVF) where multiple embryos are transferred into the uterus.
Triplet pregnancies carry a higher risk of complications for both the mother and the offsprings compared to singleton or twin pregnancies, including preterm labor, low birth weight, and developmental issues. As such, they often require close monitoring and specialized care throughout the pregnancy.
Multiple pregnancy is a type of gestation where more than one fetus is carried simultaneously in the uterus. The most common forms of multiple pregnancies are twins (two fetuses), triplets (three fetuses), and quadruplets (four fetuses). Multiple pregnancies can occur when a single fertilized egg splits into two or more embryos (monozygotic) or when more than one egg is released and gets fertilized during ovulation (dizygotic). The risk of multiple pregnancies increases with the use of assisted reproductive technologies, such as in vitro fertilization. Multiple pregnancies are associated with higher risks for both the mother and the fetuses, including preterm labor, low birth weight, and other complications.
Pregnancy reduction, multifetal refers to the medical procedure used to decrease the number of fetuses in a multiple pregnancy, such as twins or higher-order multiples (triplets, quadruplets, etc.). This is also known as selective reduction or selective termination. The goal of this procedure is to reduce the risk of complications associated with multifetal pregnancies, including preterm labor, low birth weight, and pregnancy loss.
The procedure typically involves an ultrasound-guided injection of a medication that stops the development of one or more fetuses. This is usually performed during the first trimester of pregnancy. The decision to undergo pregnancy reduction is often based on a variety of factors, including maternal age, medical history, and personal preferences. It's important to note that this procedure carries its own risks, such as infection, bleeding, and loss of the remaining fetuses, so it should be carefully considered and discussed with healthcare providers.
Quintuplets are defined in medical terms as a rare type of multiple pregnancy where a woman gives birth to five offspring at once. This occurs when one fertilized egg divides into five embryos, a phenomenon known as monozygotic quintuplets. Each baby shares the same genetic material and may be of the same sex. Quintuplets have a higher risk of preterm birth and other complications compared to singleton pregnancies. The survival rate for quintuplets has improved significantly over time due to advancements in medical technology and neonatal care.
An anticodon is a sequence of three ribonucleotides (RNA bases) in a transfer RNA (tRNA) molecule that pair with a complementary codon in a messenger RNA (mRNA) molecule during protein synthesis. This interaction occurs within the ribosome during translation, where the genetic code in the mRNA is translated into an amino acid sequence in a polypeptide. Specifically, each tRNA carries a specific amino acid that corresponds to its anticodon sequence, allowing for the accurate and systematic addition of amino acids to the growing polypeptide chain.
In summary, an anticodon is a crucial component of the translation machinery, facilitating the precise decoding of genetic information and enabling the synthesis of proteins according to the instructions encoded in mRNA molecules.
The genetic code is the set of rules that dictates how DNA and RNA sequences are translated into proteins. It consists of a 64-unit "alphabet" formed by all possible combinations of four nucleotide bases - adenine (A), guanine (G), cytosine (C), and thymine (T) in DNA or uracil (U) in RNA. These triplets, also known as codons, specify the addition of specific amino acids during protein synthesis or signal the start or stop of translation. This code is universal across all known organisms, with only a few exceptions.
In the field of medicine, twins are defined as two offspring produced by the same pregnancy. They can be either monozygotic (identical) or dizygotic (fraternal). Monozygotic twins develop from a single fertilized egg that splits into two separate embryos, resulting in individuals who share identical genetic material. Dizygotic twins, on the other hand, result from the fertilization of two separate eggs by two different sperm cells, leading to siblings who share about 50% of their genetic material, similar to non-twin siblings.