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Multiple birth

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A multiple birth is the culmination of one multiple pregnancy , wherein the mother gives birth to two or more babies. A term most applicable to vertebrate species, multiple births occur in most kinds of mammals , with varying frequencies. Such births are often named according to the number of offspring, as in twins and triplets . In non-humans, the whole group may also be referred to as a litter , and multiple births may be more common than single births. Multiple births in humans are the exception and can be exceptionally rare in the largest mammals.

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100-425: A multiple pregnancy may be the result of the fertilization of a single egg that then splits to create identical fetuses , or it may be the result of the fertilization of multiple eggs that create fraternal ("non-identical") fetuses, or it may be a combination of these factors. A multiple pregnancy from a single zygote is called monozygotic , from two zygotes is called dizygotic , or from three or more zygotes

200-416: A nutrient -rich tissue , inside the seed . The two central-cell maternal nuclei (polar nuclei) that contribute to the endosperm arise by mitosis from the single meiotic product that also gave rise to the egg. Therefore, maternal contribution to the genetic constitution of the triploid endosperm is double that of the embryo. One primitive species of flowering plant, Nuphar polysepala , has endosperm that

300-407: A few days after; therefore, in most mammals, it is more common for ejaculation to precede ovulation than vice versa. When sperm are deposited into the anterior vagina, they are not capable of fertilisation (i.e., non-capacitated) and are characterised by slow linear motility patterns. This motility, combined with muscular contractions enables sperm transport towards the uterus and oviducts . There

400-419: A high-calorie diet to increase the birth weights of the babies. Evidence around this subject is not yet good enough to advise women to do this because the long term effects of the high-calorie diets on the mother are not known. A study in 2013 involving 106 participating centers in 25 countries came to the conclusion that, in a twin pregnancy of a gestational age between 32 weeks 0 days and 38 weeks 6 days, and

500-435: A higher mortality rate. It is more common for multiple births to be stillborn, while for singletons the risk is not as high. A literary review on multiple pregnancies shows a study done on one set each of septuplets and octuplets, two sets of sextuplets, 8 sets of quintuplets, 17 sets of quadruplets, and 228 sets of triplets. By doing this study, Hammond found that the mean gestational age (how many weeks when birthed) at birth

600-537: A mixture of identical and fraternal siblings, such as three identical and one fraternal, two identical and two fraternal, or two pairs of identicals. One famous set of identical quadruplets was the Genain quadruplets , all of whom developed schizophrenia . Quadruplets are sometimes referred to as "quads" in Britain. Quintuplets occur naturally in 1 in 55,000,000 births. The first quintuplets known to survive infancy were

700-420: A more violent and rapid non-linear motility pattern as sperm approach the oocyte. The capacitated spermatozoon and the oocyte meet and interact in the ampulla of the fallopian tube . Rheotaxis, thermotaxis and chemotaxis are known mechanisms that guide sperm towards the egg during the final stage of sperm migration. Spermatozoa respond (see Sperm thermotaxis ) to the temperature gradient of ~2 °C between

800-451: A multiple pregnancy are also encouraged after 24 weeks to be on bed rest. This recommendation is not a requirement for women with a multiple pregnancy, but it has been used as a method to prevent complications. Some doctors may prescribe this method to be on the safe side and if they believe it is necessary. As preterm birth is such a risk for women with multiple pregnancies, it has been suggested that these women should be encouraged to follow

900-417: A multiple pregnancy; it is also called "multifetal reduction". The procedure generally takes two days; the first day for testing in order to select which fetuses to remove, and the second day for the procedure itself, in which potassium chloride is injected into the heart of each selected fetus under the guidance of ultrasound imaging. Risks of the procedure include bleeding requiring transfusion, rupture of

1000-543: A result of preterm birth , multiples tend to have lower birth weight than singletons. Exceptions are possible, however, as with the Kupresak triplets, born in 2008 in Mississauga , Ontario , Canada. Their combined weight was 17 lbs, 2.7 oz, which set a world record. Two of the triplets were similar in size and, as expected, moderately low birth weight. The two combined weighed 9 lbs, 2.7 oz. The third triplet, however,

1100-517: A short period lasting some days; a queen may mate with eight or more drones . She then stores the sperm for the rest of her life, perhaps for five years or more. In many fungi (except chytrids ), as in some protists, fertilisation is a two step process. First, the cytoplasms of the two gamete cells fuse (called plasmogamy ), producing a dikaryotic or heterokaryotic cell with multiple nuclei. This cell may then divide to produce dikaryotic or heterokaryotic hyphae . The second step of fertilisation

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1200-567: A subject of semantic arguments about the beginning of pregnancy , typically in the context of the abortion debate. Upon gastrulation , which occurs around 16 days after fertilisation, the implanted blastocyst develops three germ layers, the endoderm, the ectoderm and the mesoderm, and the genetic code of the father becomes fully involved in the development of the embryo; later twinning is impossible. Additionally, interspecies hybrids survive only until gastrulation and cannot further develop. However, some human developmental biology literature refers to

1300-525: A sugar free pollen germination medium and a medium with purified TTS proteins both grew. However, in the TTS medium, the tubes grew at a rate 3x that of the sugar-free medium. TTS proteins were also placed on various locations of semi in vivo pollinated pistils, and pollen tubes were observed to immediately extend toward the proteins. Transgenic plants lacking the ability to produce TTS proteins had slower pollen tube growth and reduced fertility. The rupture of

1400-478: A thick layer of extracellular matrix that surrounds the egg and is similar to the role of the vitelline membrane in sea urchins, binds the sperm. Unlike sea urchins, the sperm binds to the egg before the acrosomal reaction. ZP3 , a glycoprotein in the zona pellucida, is responsible for egg/sperm adhesion in humans. The receptor galactosyltransferase (GalT) binds to the N-acetylglucosamine residues on

1500-400: A thin spike at the head of the sperm called the acrosomal process . The sperm binds to the egg through another ligand reaction between receptors on the vitelline membrane . The sperm surface protein bindin, binds to a receptor on the vitelline membrane identified as EBR1. Fusion of the plasma membranes of the sperm and egg are likely mediated by bindin. At the site of contact, fusion causes

1600-448: Is karyogamy , the fusion of the nuclei to form a diploid zygote. In chytrid fungi, fertilisation occurs in a single step with the fusion of gametes, as in animals and plants. There are three types of fertilisation processes in protozoa: Algae, like some land plants, undergo alternation of generations . Some algae are isomorphic, where both the sporophyte (2n) and gameteophyte (n) are the same morphologically. When algae reproduction

1700-559: Is a U.S. hospital located in the Baltimore suburb of Towson, Maryland . It was opened in 1965. GBMC serves more than 20,455 inpatient cases and approximately 52,000 emergency department visits annually. GBMC's main campus includes three medical office buildings—Physicians Pavilion East, Physicians Pavilion West, and Physicians Pavilion North I. In addition to its main campus located in Towson, GBMC has several facilities located throughout

1800-448: Is a pH gradient within the micro-environment of the female reproductive tract such that the pH near the vaginal opening is lower (approximately 5) than the oviducts (approximately 8). The sperm-specific pH-sensitive calcium transport protein called CatSper increases the sperm cell permeability to calcium as it moves further into the reproductive tract. Intracellular calcium influx contributes to sperm capacitation and hyperactivation, causing

1900-610: Is also estimated that about 42% of flowering plants exhibit a mixed mating system in nature. In the most common kind of mixed mating system, individual plants produce a single type of flower and fruits may contain self-fertilised, outcrossed or a mixture of progeny types. The transition from cross-fertilisation to self-fertilisation is the most common evolutionary transition in plants, and has occurred repeatedly in many independent lineages. About 10-15% of flowering plants are predominantly self-fertilising. Under circumstances where pollinators or mates are rare, self-fertilisation offers

2000-600: Is called polyzygotic . Similarly, the siblings themselves from a multiple birth may be referred to as monozygotic if they are identical or as dizygotic (in cases of twins) or polyzygotic (for three or more siblings) if they are fraternal, i.e., non-identical. Each fertilized ovum ( zygote ) may produce a single embryo , or it may split into two or more embryos, each carrying the same genetic material. Fetuses resulting from different zygotes are called fraternal and share only 50% of their genetic material, as ordinary full siblings from separate births do. Fetuses resulting from

2100-402: Is described as oogamous, the male and female gametes are different morphologically, where there is a large non-motile egg for female gametes, and the male gamete are uniflagellate (motile). Via the process of syngamy, these will form a new zygote, regenerating the sporophyte generation again. Meiosis results in a random segregation of the genes that each parent contributes. Each parent organism

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2200-405: Is diploid, resulting from the fusion of a sperm with one, rather than two, maternal nuclei. It is believed that early in the development of angiosperm lineages, there was a duplication in this mode of reproduction, producing seven-celled/eight-nucleate female gametophytes, and triploid endosperms with a 2:1 maternal to paternal genome ratio. In many plants, the development of the flesh of the fruit

2300-525: Is due to the higher level of follicle-stimulating hormone that older women sometimes have as their ovaries respond more slowly to FSH stimulation. The number of multiple births has increased since the late 1970s. For example, in Canada between 1979 and 1999, the number of multiple birth babies increased 35%. Before the advent of ovulation-stimulating drugs, triplets were quite rare (approximately 1 in 8000 births) and higher-order births much rarer still. Much of

2400-500: Is lowest in the womb) is head down there is no good evidence that caesarean section will be safer than a vaginal birth for the mother or babies. Monoamniotic twins (twins that form after the splitting of a fertilised egg and share the same amniotic fluid sac) are at more risk of complications than twins that have their own sacs. There is also insufficient evidence around whether to deliver the babies early by caesarean section or to wait for labour to start naturally while running checks on

2500-473: Is proportional to the percentage of fertilised ovules. For example, with watermelon , about a thousand grains of pollen must be delivered and spread evenly on the three lobes of the stigma to make a normal sized and shaped fruit. Outcrossing , or cross-fertilisation, and self-fertilisation represent different strategies with differing benefits and costs. An estimated 48.7% of plant species are either dioecious or self-incompatible obligate outcrossers. It

2600-499: Is random, due to the egg splitting, so all parents have an equal chance of conceiving identical twins. Triplets can be either fraternal, identical, or a combination of both. The most common are strictly fraternal triplets, which come from a polyzygotic pregnancy of three eggs. Less common are triplets from a dizygotic pregnancy, where one zygote divides into two identical fetuses, and the other does not. Least common are identical triplets, three fetuses from one egg. In this case, sometimes

2700-738: Is registered with the state of Maryland as an approved charitable organization . Gifts to the GBMC Foundation support new facilities, equipment for GBMC physicians and staff, specialty programs, and technologies that combine to make GBMC the community hospital of choice for residents of Central Maryland. In 2007, GBMC and Johns Hopkins Medicine began a strategic clinical affiliation for several programs, beginning with cardiology , pediatric surgery , and oncology . Additional joint clinical practices, shared satellite healthcare centers, and collaboration on clinical research are possibilities for future expansion of this affiliation. In late 2020, GBMC

2800-524: Is required, there are inpatient hospice facilities in three locations: Founded in 1987, the GBMC Foundation is a 501(c)(3) nonprofit organization established to centralize and coordinate fundraising efforts to benefit GBMC HealthCare. The Foundation executes fundraising events, annual appeals, and capital campaigns and seeks gifts from patients, as well as grants from corporations and private foundations. The Foundation does not have any affiliation with federated funds or public agencies. The GBMC Foundation

2900-680: Is the Gosselin sextuplets , born on May 10, 2004, in Hershey, Pennsylvania . Reality television shows Jon & Kate Plus 8 and later Kate Plus 8 have chronicled the lives of these sextuplets. Other shows of this nature include Table for 12 and Sweet Home Sextuplets . In 1997, the McCaughey septuplets , born in Des Moines, Iowa , became the first septuplets known to survive infancy. The first surviving set of octuplets on record are

3000-474: Is the fusion of gametes to give rise to a zygote and initiate its development into a new individual organism or offspring. While processes such as insemination or pollination , which happen before the fusion of gametes, are also sometimes informally referred to as fertilisation, these are technically separate processes. The cycle of fertilisation and development of new individuals is called sexual reproduction . During double fertilisation in angiosperms ,

3100-413: Is the process in angiosperms (flowering plants) in which two sperm from each pollen tube fertilise two cells in a female gametophyte (sometimes called an embryo sac) that is inside an ovule. After the pollen tube enters the gametophyte, the pollen tube nucleus disintegrates and the two sperm cells are released; one of the two sperm cells fertilises the egg cell (at the bottom of the gametophyte near

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3200-429: Is unclear. News articles and other non-scientific organizations give odds from one in 60,000 to one in 200 million pregnancies. Quadruplets are much rarer than twins or triplets. As of 2007, there were approximately 3,556 sets recorded worldwide. Quadruplet births are becoming increasingly common due to fertility treatments . There are around 70 sets of all-identical quadruplets worldwide. Many sets of quadruplets contain

3300-601: Is usually identical save for a fraction of their genes; each gamete is therefore genetically unique. At fertilisation, parental chromosomes combine. In humans , (2²²)² = 17.6x10 chromosomally different zygotes are possible for the non-sex chromosomes, even assuming no chromosomal crossover . If crossover occurs once, then on average (4²²)² = 309x10 genetically different zygotes are possible for every couple, not considering that crossover events can take place at most points along each chromosome. The X and Y chromosomes undergo no crossover events and are therefore excluded from

3400-559: The conceptus and such medical literature refers to the "products of conception" as the post-implantation embryo and its surrounding membranes. The term "conception" is not usually used in scientific literature because of its variable definition and connotation. Insects in different groups, including the Odonata ( dragonflies and damselflies ) and the Hymenoptera ( ants , bees , and wasps ) practise delayed fertilisation. Among

3500-1048: The Suleman octuplets , born in 2009 in Bellflower, California . In 2019, all 8 children celebrated their 10th birthday. Multiple births of as many as 9 babies have been born alive; In May 2021, the Cissé nonuplets were born in Morocco to Halima Cissé , a 25-year-old woman from Mali . As of May 2023, two years since their births, all 9 are still living and reportedly in good health. The list of multiple births covers notable examples. The frequency of N multiple births from natural pregnancies has been given as approximately 1:89 ( Hellin's law ) and as about 1:80. This gives: North American dizygotic twinning occurs about once in 83 conceptions, and triplets about once in 8000 conceptions. US figures for 2010 were: Human multiple births can occur either naturally (the woman ovulates multiple eggs or

3600-436: The fruit . With multi-seeded fruits, multiple grains of pollen are necessary for syngamy with each ovule. The growth of the pollen tube is controlled by the vegetative (or tube) cytoplasm. Hydrolytic enzymes are secreted by the pollen tube that digest the female tissue as the tube grows down the stigma and style; the digested tissue is used as a nutrient source for the pollen tube as it grows. During pollen tube growth towards

3700-426: The haploid male gamete combines with two haploid polar nuclei to form a triploid primary endosperm nucleus by the process of vegetative fertilisation. In antiquity, Aristotle conceived the formation of new individuals through fusion of male and female fluids, with form and function emerging gradually, in a mode called by him as epigenetic . In 1784, Spallanzani established the need of interaction between

3800-407: The pollen grain germinates , and a pollen tube grows and penetrates the ovule through a tiny pore called a micropyle . The sperm are transferred from the pollen through the pollen tube to the ovule where the egg is fertilised. In flowering plants , two sperm cells are released from the pollen tube, and a second fertilisation event occurs involving the second sperm cell and the central cell of

3900-635: The Hospital for Women of Maryland in Baltimore City and Presbyterian Eye, Ear and Throat Charity Hospital. GBMC opened its doors in 1965 as a regional medical center, providing general acute and specific specialized services to the northern portion of Baltimore City, most of Baltimore County, and portions of Anne Arundel, Carroll, Harford, and Howard counties. The Hospital for Women of Maryland in Baltimore City had opened in 1882 in Bolton Hill as

4000-656: The Iranian government provides free housing to families that have birthed quintuplets. A study by the U.S. Agency for Healthcare Research and Quality found that, in 2011, pregnant women covered by private insurance in the United States were older and more likely to have multiple gestation than women covered by Medicaid . Fertilization This is an accepted version of this page Fertilisation or fertilization (see spelling differences ), also known as generative fertilisation , syngamy and impregnation ,

4100-506: The Odonata, females may mate with multiple males, and store sperm until the eggs are laid. The male may hover above the female during egg-laying (oviposition) to prevent her from mating with other males and replacing his sperm; in some groups such as the darters, the male continues to grasp the female with his claspers during egg-laying, the pair flying around in tandem. Among social Hymenoptera, honeybee queens mate only on mating flights, in

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4200-441: The U.S. during 2015, about one in a million. According to Victor Khouzami, Chairman of Obstetrics at Greater Baltimore Medical Center , "No one really knows the incidence". Identical triplets or quadruplets are very rare and result when the original fertilized egg splits and then one of the resultant cells splits again (for triplets) or, even more rarely, a further split occurs (for quadruplets). The odds of having identical triplets

4300-525: The US. Without fertility treatments, the probability is about 1 in 60; with fertility treatments, it can be as high as 20-25%. Dizygotic (fraternal) twins can be caused by a hyperovulation gene in the mother. Although the father's genes do not influence the woman's chances of having twins, he could influence his children's chances of having twins by passing on a copy of the hyperovulation gene to them. Monozygotic (identical) twins do not run in families. The twinning

4400-423: The United States were delivered by Cesarean section in 2008. Also in comparison, the rate of Cesarean section for all pregnancies in the general population varies between 40% and 14%. Fetal position (the way the babies are lying in the womb) usually determines if they are delivered by caesarean section or vaginally. A review of good quality research on this subject found that if the twin that will be born first (i.e.

4500-469: The Vegetable Kingdom (pages 466-467) summed up his findings in the following way. "It has been shown in the present volume that the offspring from the union of two distinct individuals, especially if their progenitors have been subjected to very different conditions, have an immense advantage in height, weight, constitutional vigour and fertility over the self-fertilised offspring from one of

4600-557: The ZP3 and is important for binding with the sperm and activating the acrosome reaction. ZP3 is sufficient though unnecessary for sperm/egg binding. Two additional sperm receptors exist: a 250kD protein that binds to an oviduct secreted protein, and SED1, which independently binds to the zona. After the acrosome reaction, the sperm is believed to remain bound to the zona pellucida through exposed ZP2 receptors. These receptors are unknown in mice but have been identified in guinea pigs. In mammals,

4700-469: The ability to store sperm for extended periods of time and can fertilise their eggs at their own desire. Oviparous animals producing eggs with thin tertiary membranes or no membranes at all, on the other hand, use external fertilisation methods. Such animals may be more precisely termed ovuliparous. External fertilisation is advantageous in that it minimises contact (which decreases the risk of disease transmission), and greater genetic variation. Sperm find

4800-406: The actual persistence of meiosis and self-fertilisation as a form of reproduction in long-established self-fertilising plants may be related to the immediate benefit of efficient recombinational repair of DNA damage during formation of germ cells provided by meiosis at each generation. The mechanics behind fertilisation has been studied extensively in sea urchins and mice. This research addresses

4900-400: The advantage of reproductive assurance . Self-fertilisation can therefore result in improved colonisation ability. In some species, self-fertilisation has persisted over many generations. Capsella rubella is a self-fertilising species that became self-compatible 50,000 to 100,000 years ago. Arabidopsis thaliana is a predominantly self-fertilising plant with an out-crossing rate in

5000-541: The age of 35 increase the risk of having fetuses with certain conditions and complications that are not as common in women who are pregnant. The increasing use of fertility drugs and consequent increased rate of multiple births has made the phenomenon of multiples more frequent and hence more visible. In 2004 the birth of sextuplets, six children, to Pennsylvania couple Kate and Jon Gosselin helped them to launch their television series, originally Jon & Kate Plus 8 and (following their divorce) Kate Plus 8 , which became

5100-409: The babies' wellbeing. The birth of this type of twins should therefore be decided with the mother and her family and should take into account the need for good neonatal care services. Cesarean delivery is needed when first twin is in non cephalic presentation or when it is a monoamniotic twin pregnancy. Multiple-birth infants are usually admitted to neonatal intensive care or a special care nursery in

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5200-467: The binding of the spermatozoon to the GalT initiates the acrosome reaction . This process releases the hyaluronidase that digests the matrix of hyaluronic acid in the vestments around the oocyte. Additionally, heparin-like glycosaminoglycans (GAGs) are released near the oocyte that promote the acrosome reaction. Fusion between the oocyte plasma membranes and sperm follows and allows the sperm nucleus ,

5300-467: The calculation. The mitochondrial DNA is only inherited from the maternal parent. Shortly after the sperm fuse with the egg, the two sperm centrioles form the embryo first centrosome and microtubule aster . The sperm centriole, found near the male pronucleus, recruit egg Pericentriolar material proteins forming the zygote first centrosome. This centrosome nucleates microtubules in the shape of stars called astral microtubules. The microtubules span

5400-504: The community including in Hereford , Hunt Manor, Hunt Valley , Owings Mills , Perry Hall , Lutherville , Phoenix , and Timonium . GBMC HealthCare is a private, not-for-profit corporation that owns and operates Greater Baltimore Medical Center. GBMC HealthCare also owns and operates Gilchrist Hospice Care (formerly known as Hospice of Baltimore and Gilchrist Center for Hospice Care), the largest not-for-profit hospice organization in

5500-555: The egg to develop without fertilisation or syngamy. The sperm may enter the egg. Hybridogenesis : One genome is eliminated to produce haploid eggs. Canina meiosis : (sometimes called "permanent odd polyploidy") one genome is transmitted in the Mendelian fashion, others are transmitted clonally. The major benefit of cross-fertilisation is generally thought to be the avoidance of inbreeding depression . Charles Darwin , in his 1876 book The Effects of Cross and Self Fertilisation in

5600-405: The eggs via chemotaxis , a type of ligand/receptor interaction. Resact is a 14 amino acid peptide purified from the jelly coat of A. punctulata that attracts the migration of sperm. After finding the egg, the sperm penetrates the jelly coat through a process called sperm activation. In another ligand/receptor interaction, an oligosaccharide component of the egg binds and activates a receptor on

5700-585: The female's ovum and male's sperm to form a zygote in frogs. In 1827, Karl Ernst von Baer observed a therian mammalian egg for the first time. Oscar Hertwig (1876), in Germany, described the fusion of nuclei of spermatozoa and of ova from sea urchin . The evolution of fertilisation is related to the origin of meiosis , as both are part of sexual reproduction , originated in eukaryotes . One hypothesis states that meiosis originated from mitosis. The gametes that participate in fertilisation of plants are

5800-415: The fertilized egg splits into two) or as the result of infertility treatments such as in vitro fertilization (several embryos are often transferred to compensate for lower quality) or fertility drugs (which can cause multiple eggs to mature in one ovulatory cycle). For reasons that are not yet known, the older a woman is, the more likely she is to have a multiple birth naturally. It is theorized that this

5900-460: The fetuses are surrounded by one or more placentas ( chorionicity ) and amniotic sacs ( amnionicity ). In humans, the average length of pregnancy (2 weeks fewer than gestation ) is 38 weeks with a single fetus. This average decreases for each additional fetus: to 36 weeks for twin births, 32 weeks for triplets, and 30 weeks for quadruplets. With the decreasing gestation time, the risks from immaturity at birth and subsequent viability increase with

6000-457: The first twin is in cephalic presentation , planned Cesarean section does not significantly decrease or increase the risk of fetal or neonatal death or serious neonatal disability , as compared with planned vaginal delivery. In this study, 44% of the women planned for vaginal delivery still ended up having Cesarean section for unplanned reasons such as pregnancy complications . In comparison, it has been estimated that 75% of twin pregnancies in

6100-441: The formation of a diploid cell called a zygote . The zygote divides to form a blastocyst and, upon entering the uterus, implants in the endometrium, beginning pregnancy . Embryonic implantation not in the uterine wall results in an ectopic pregnancy that can kill the mother. In such animals as rabbits, coitus induces ovulation by stimulating the release of the pituitary hormone gonadotropin; this release greatly increases

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6200-399: The formation of a fertilisation cone . Mammals internally fertilise through copulation . After a male ejaculates , many sperm move to the upper vagina (via contractions from the vagina) through the cervix and across the length of the uterus to meet the ovum. In cases where fertilisation occurs, the female usually ovulates during a period that extends from hours before copulation to

6300-456: The highest-rated show on the TLC network. Babies born from multiple-birth pregnancies are much more likely to result in premature birth than those from single pregnancies. 51% of twins and 91% of triplets are born preterm, compared to 9.4% in singletons. 14% of twins and 41% of triplets are even born very preterm , compared to 1.7% in singletons. Drugs known as betamimetics can be used to relax

6400-409: The hospital immediately after being born. The records for all the triplet pregnancies managed and delivered from 1992 to 1996 were looked over to see what the neonatal statistics were. Kaufman found from reviewing these files that during a five-year period, 55 triplet pregnancies (i.e. 165 babies) were delivered. Of the 165 babies 149 were admitted to neonatal intensive care after the delivery. In Iran,

6500-799: The identical female Canadian Dionne quintuplets , born in 1934. Quintuplets are sometimes referred to as "quins" in the UK and "quints" in North America. A famous set of all-girl quintuplets are the Busby quints from the TV series OutDaughtered . Born in Liverpool , England , on November 18, 1983, the Walton sextuplets were the world's first all-female surviving sextuplets, and the world's fourth known set of surviving sextuplets. Another well-known set of sextuplets

6600-460: The increase can probably be attributed to the impact of fertility treatments, such as in-vitro fertilization . Younger patients who undergo treatment with fertility medication containing artificial FSH , followed by intrauterine insemination , are particularly at risk for multiple births of higher order. Certain factors appear to increase the likelihood that a woman will naturally conceive multiples. These include: Women conceiving multiples over

6700-541: The likelihood of pregnancy. Fertilisation in humans is the union of a human egg and sperm , usually occurring in the ampulla of the fallopian tube , producing a single celled zygote , the first stage of life in the development of a genetically unique organism, and initiating embryonic development . Scientists discovered the dynamics of human fertilisation in the nineteenth century. The term conception commonly refers to "the process of becoming pregnant involving fertilisation or implantation or both". Its use makes it

6800-409: The micropyle (an opening in the ovule wall) and the pollen tube "bursts" into the embryo sac, releasing sperm. The growth of the pollen tube has been believed to depend on chemical cues from the pistil, however these mechanisms were poorly understood until 1995. Work done on tobacco plants revealed a family of glycoproteins called TTS proteins that enhanced growth of pollen tubes. Pollen tubes in

6900-411: The micropyle), forming a diploid (2n) zygote . This is the point when fertilisation actually occurs; pollination and fertilisation are two separate processes. The nucleus of the other sperm cell fuses with two haploid polar nuclei (contained in the central cell) in the centre of the gametophyte. The resulting cell is triploid (3n). This triploid cell divides through mitosis and forms the endosperm ,

7000-415: The mother, or in some cases genetically differ from her but inherit only part of her DNA. Parthenogenesis occurs in many plants and animals and may be induced in others through a chemical or electrical stimulus to the egg cell. In 2004, Japanese researchers led by Tomohiro Kono succeeded after 457 attempts to merge the ova of two mice by blocking certain proteins that would normally prevent the possibility;

7100-412: The muscles of the uterus and delay birth in singleton pregnancies. There is some evidence that these drugs can also reduce the risk of preterm birth for twin pregnancies, but existing studies are small. More data is required before solid conclusions can be drawn. Likewise, existing studies are too small to determine if a cervical suture is effective for reducing prematurity in cases of multiple birth. As

7200-424: The number of embryos per embryo transfer to one or two. That way, the risks for the mother and fetuses are decreased. The appropriate number of embryos to be transferred depends on the age of the woman, whether it is the first, second or third full IVF cycle attempt and whether there are top-quality embryos available. According to a guideline from The National Institute for Health and Care Excellence (NICE) in 2013,

7300-400: The number of embryos transferred in a cycle should be chosen as in following table: Also, it is recommended to use single embryo transfer in all situations if a top-quality blastocyst is available. Bed rest has not been found to change outcomes and therefore is not generally recommended outside of a research study. Selective reduction is the practice of reducing the number of fetuses in

7400-630: The original zygote divides into two and then one of those two zygotes divides again but the other does not, or the original zygote divides into three. Triplets are far less common than twins, according to the U.S. Centers for Disease Control and Prevention, accounting for only about 4,300 sets in 3.9 million births, just a little more than .1%, or 1 in 1,000. According to the American Society of Reproductive Medicine , only about 10% of these are identical triplets: about 1 in ten thousand. Nevertheless, only 4 sets of identical triplets were reported in

7500-421: The ovary, the generative nucleus divides to produce two separate sperm nuclei (haploid number of chromosomes) – a growing pollen tube therefore contains three separate nuclei, two sperm and one tube. The sperms are interconnected and dimorphic, the large one, in a number of plants, is also linked to the tube nucleus and the interconnected sperm and the tube nucleus form the "male germ unit". Double fertilisation

7600-444: The oviduct and the ampulla, and chemotactic gradients of progesterone have been confirmed as the signal emanating from the cumulus oophorus cells surrounding rabbit and human oocytes. Capacitated and hyperactivated sperm respond to these gradients by changing their behaviour and moving towards the cumulus-oocyte complex. Other chemotactic signals such as formyl Met-Leu-Phe (fMLF) may also guide spermatozoa. The zona pellucida ,

7700-405: The ovule, which is a second female gamete. Unlike animal sperm which is motile, the sperm of most seed plants is immotile and relies on the pollen tube to carry it to the ovule where the sperm is released. The pollen tube penetrates the stigma and elongates through the extracellular matrix of the style before reaching the ovary. Then near the receptacle, it breaks through the ovule through

7800-603: The pollen tube to release sperm in Arabidopsis has been shown to depend on a signal from the female gametophyte. Specific proteins called FER protein kinases present in the ovule control the production of highly reactive derivatives of oxygen called reactive oxygen species (ROS). ROS levels have been shown via GFP to be at their highest during floral stages when the ovule is the most receptive to pollen tubes, and lowest during times of development and following fertilisation. High amounts of ROS activate Calcium ion channels in

7900-491: The pollen tube, causing these channels to take up Calcium ions in large amounts. This increased uptake of calcium causes the pollen tube to rupture, and release its sperm into the ovule. Pistil feeding assays in which plants were fed diphenyl iodonium chloride (DPI) suppressed ROS concentrations in Arabidopsis , which in turn prevented pollen tube rupture. After being fertilised, the ovary starts to swell and develop into

8000-546: The question of how the sperm and the appropriate egg find each other and the question of how only one sperm gets into the egg and delivers its contents. There are three steps to fertilisation that ensure species-specificity: Consideration as to whether an animal (more specifically a vertebrate) uses internal or external fertilisation is often dependent on the method of birth. Oviparous animals laying eggs with thick calcium shells, such as chickens , or thick leathery shells generally reproduce via internal fertilisation so that

8100-482: The result of in vitro fertilisation (IVF). In a 1997 study of 2,173 embryo transfers performed as part of in vitro fertilisation (IVF), 34% were successfully delivered pregnancies. The overall multiple pregnancy rate was 31.3% (24.7% twins, 5.8% triplets, and .08% quadruplets). Because IVFs are producing more multiples, a number of efforts are being made to reduce the risk of multiple births- specifically triplets or more. Medical practitioners are doing this by limiting

8200-465: The resulting embryo normally developed into a mouse. Allogamy , which is also known as cross-fertilisation, refers to the fertilisation of an egg cell from one individual with the male gamete of another. Autogamy which is also known as self-fertilisation, occurs in such hermaphroditic organisms as plants and flatworms; therein, two gametes from one individual fuse. Some relatively unusual forms of reproduction are: Gynogenesis : A sperm stimulates

8300-536: The risk is greatest include attention deficit hyperactivity disorder , autism spectrum disorder , and anxiety disorders. Multiples may be monochorionic , sharing the same chorion , with resultant risk of twin-to-twin transfusion syndrome . Monochorionic multiples may even be monoamniotic , sharing the same amniotic sac , resulting in risk of umbilical cord compression and nuchal cord . In very rare cases, there may be conjoined twins , possibly impairing function of internal organs. Multiples are also known to have

8400-425: The risks that multiple pregnancies carried for the mother and for the fetuses. Women with a multiple pregnancy are usually seen more regularly by midwives or doctors than those with singleton pregnancies because of the higher risks of complications. However, there is currently no evidence to suggest that specialised antenatal services produce better outcomes for mother or babies than 'normal' antenatal care. Women with

8500-443: The same parents. And this fact is amply sufficient to account for the development of the sexual elements, that is, for the genesis of the two sexes." In addition, it is thought by some, that a long-term advantage of out-crossing in nature is increased genetic variability that promotes adaptation or avoidance of extinction (see Genetic variability ). Greater Baltimore Medical Center Greater Baltimore Medical Center ( GBMC )

8600-430: The same zygote share 100% of their genetic material and hence are called identical . Identical twins are always the same sex. Terms used for the number of offspring in a multiple birth, where a number higher than three ends with the suffix -uplet : Terms used for multiple births or the genetic relationships of their offspring are based on the zygosity of the pregnancy: Multiple pregnancies are also classified by how

8700-645: The second women's hospital in the country (in 2001 the Hospital for Women was repurposed into the Meyerhoff House, a student housing facility for the Maryland Institute College of Art ). The Presbyterian Eye, Ear and Throat Charity Hospital originated as a clinic in the Civil War surgeon's East Baltimore carriage house in 1887. Since moving to Towson from Baltimore City, GBMC has shared adjacency to Towson University . In 2020, GBMC

8800-672: The size of the sibling group. Only as of the twentieth century have more than four all survived infancy. Recent history has also seen increasing numbers of multiple births. In the United States, it has been estimated that by 2011, 36% of twin births, and 78% of triplet and higher-order births resulted from conception by assisted reproductive technology . Twins are by far the most common form of multiple births in humans. The U.S. Centers for Disease Control and Prevention report more than 132,000 sets of twins out of 3.9 million births of all kinds each year, about 3.4%, or 1 in 30. Compared to other multiple births, twin births account for 97% of them in

8900-410: The sperm (male) and the egg (female) cell. Various plant groups have differing methods by which the gametes produced by the male and female gametophytes come together and are fertilised. In bryophytes and pteridophytic land plants, fertilisation of the sperm and egg takes place within the archegonium . In seed plants , the male gametophyte is formed within a pollen grain. After pollination ,

9000-435: The sperm and causes the acrosomal reaction . The acrosomal vesicles of the sperm fuse with the plasma membrane and are released. In this process, molecules bound to the acrosomal vesicle membrane, such as bindin, are exposed on the surface of the sperm. These contents digest the jelly coat and eventually the vitelline membrane. In addition to the release of acrosomal vesicles, there is explosive polymerisation of actin to form

9100-501: The sperm fertilises the egg without having to pass through the thick, protective, tertiary layer of the egg. Ovoviviparous and viviparous animals also use internal fertilisation. Although some organisms reproduce via amplexus , they may still use internal fertilisation, as with some salamanders. Advantages of internal fertilisation include minimal waste of gametes, greater chance of individual egg fertilisation, longer period of egg protection, and selective fertilisation. Many females have

9200-418: The state of Maryland. Since 1994, it has provided services to over 17,000 terminally ill individuals who reside in Baltimore City and Baltimore, Carroll, Harford, and Howard counties. Services include medical, nursing, social work, home health aid, spiritual and bereavement counseling/support, and volunteer assistance. Hospice services are most often provided in the patient's home. When more intensive medical care

9300-581: The state of Maryland. The organization also includes the GBMC Foundation, which fundraises for GBMC. GBMC is a top 10 rated hospital in Baltimore as well as one of the 40 best employers in Maryland for 2023. GBMC maintains a collaborative care agreement with Sheppard Pratt , a mental health services facility and system with which it shares adjacency on the Towson campus. Incorporated in 1960, GBMC HealthCare consolidated two specialty Baltimore hospitals:

9400-488: The typical centriole , and atypical centriole that is attached to the flagellum , but not the mitochondria , to enter the oocyte. The protein CD9 likely mediates this fusion in mice (the binding homolog). The egg " activates " itself upon fusing with a single sperm cell and thereby changes its cell membrane to prevent fusion with other sperm. Zinc atoms are released during this activation. This process ultimately leads to

9500-418: The uterus, retained placenta , infection, a miscarriage, and prelabor rupture of membranes . Each of these appears to be rare. There are also ethical concerns about this procedure, since it is a form of abortion , and also because of concerns over which fetuses are terminated and why. Selective reduction was developed in the mid-1980s, as people in the field of assisted reproductive technology became aware of

9600-534: The whole valium of the egg, allowing the egg pronucleus to use the cables to get to the male pronucleus. As the male and female pronuclei approach each other, the single centrosome split into two centrosomes located in the interphase between the pronuclei. Then the centrosome via the astral microtubules polarises the genome inside the pronuclei. Organisms that normally reproduce sexually can also reproduce via parthenogenesis , wherein an unfertilised female gamete produces viable offspring. These offspring may be clones of

9700-537: The wild of less than 0.3%; a study suggested that self-fertilisation evolved roughly a million years ago or more in A. thaliana . In long-established self-fertilising plants, the masking of deleterious mutations and the production of genetic variability is infrequent and thus unlikely to provide a sufficient benefit over many generations to maintain the meiotic apparatus. Consequently, one might expect self-fertilisation to be replaced in nature by an ameiotic asexual form of reproduction that would be less costly. However

9800-436: Was 33.4 weeks for triplets and 31 weeks for quadruplets. This shows that stillbirth happens usually 3–5 weeks before the woman reaches full term and also that for sextuplets or higher it almost always ends in death of the fetuses. Though multiples are at a greater risk of being stillborn, there is inconclusive evidence whether the actual mortality rate is higher in multiples than in singletons. Today many multiple pregnancies are

9900-586: Was granted the Malcolm Baldridge National Quality Award as well as a 5-star rating from the Centers for Medicare and Medicaid Services . GBMC underwent a major renovation and revitalization construction project starting in 2021 that included 60 new inpatient beds and a new cancer institute. Gilchrist Hospice Care, a Medicare / Medicaid -certified hospice program, is the largest not-for-profit hospice organization in

10000-577: Was much larger and weighed 8 lbs. individually. Cerebral palsy is more common among multiple births than single births, being 2.3 per 1,000 survivors in singletons, 13 in twins, and 45 in triplets in North West England . This is likely a side effect of premature birth and low birth weight. Premature birth is associated with a higher risk for a breadth of behavioral and socioemotional difficulties that begin in childhood and continue through teenagehood and often into adulthood. Conditions where

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