How many triplets were born in 2011

BW discordance in triplets is common since in The most important factor in triplet BW is GA. As expected, in this sample a higher GA was associated with a higher BW in triplets.

The literature describes the occurrence of a flattening of the growth curve during the last weeks of triplet pregnancies. This growth restriction period emerges round a GA of about 36 to 37 weeks [ 17 ]. In the NTR sample only 1.

The effects of alcohol consumption and smoking during pregnancy on BW were both examined. No effect of alcohol consumption on triplet BW was seen. We hypothesize that in this sample the absence of an effect was seen because of the low maternal alcohol consumption during pregnancy.

In addition, mothers reported less consistent on alcohol consumption than on other variables. This is the effect of smoking after correcting for the GA of the triplet. The amount of loss in BW is dependent on the quantity the mother smoked during the pregnancy. In singletons an interaction between alcohol consumption and smoking has also been observed. First born TZ triplets were heavier than the second born TZ triplets, who were heavier than the third born children.

No significant birth order effect was seen in the group of MZ and DZ triplets. As the MZ and DZ groups were small, this might reflect a lack of power to detect a difference. In twins, the first born and heavier twin, has an heavier placenta and a more optimal a central instead of peripheral cord insertion [ 41 ]. Possibly triplets higher in birth order are, on average, more optimally positioned with respect to nutrients intake.

The prevalence of BW discordance is comparable with a study of Jacobs et al. Compared to singletons or twins, triplets are delayed in growth and cognitive development. There has been limited research on the effects of BW discordance, but it seems that triplets who are discordant in BW are at an even higher developmental risk than other triplets [ 43 , 44 ].

One study found that most triplets without BW discordance have caught up with singleton and twin standards on cognitive and executive functions at age 5. In contrast, BW discordant triplets still showed a lower performance on these functions at that age [ 45 ]. In the current sample, this includes We also estimated the resemblance in BW of triplets. Both were higher before correction for GA, sex and smoking than after adjusting for these factors.

This suggests that genetic as well as common environmental factors influence birth weight and that GA, sex and smoking are some of the specific common environmental factors. Children who are born SGA are at risk for asphyxia and intrauterine mortality [ 46 , 47 ].

In the Netherlands triplets are classified SGA based on singleton standards. As a result, at least half of all triplet births have to be born in tertiary referral centers with NICU facilities.

Population based triplet zygosity distributions have changed over the years. Imaizumi [ 48 ] reported that in the Netherlands, the TZ rate increased from to and decreased thereafter. This conclusion is confirmed by the present study in which ART was more common in TZ triplets than in the other zygosity groups.

Studies in singletons report that children born after ART are lower in BW than spontaneously conceived children. In twins the effect of ART is less clear, some studies find an effect, while others do not [ 49 , 50 ]. Investigators suggest that the procedure of ART itself or maternal characteristics e. In the present study we found no effect of ART. The effect was neither present in the entire triplet group, nor in the TZ triplet group. The present sample consisted of triplets who were registered at the NTR and whose parents were willing to participate in survey studies.

This led to a small positive selection bias. Triplets from families in which all three children are alive 28 days after birth also have more favorable scores on BW and GA.

Moreover, parents are possibly more willing to participate in research when the triplets are healthy compared to parents dealing with illnesses of one or more of their children. The NTR sample was more comparable with a selection of Dutch triplets that were still alive 28 after birth, than with a complete group of Dutch triplets including children who died soon after birth. A comparable positive selection bias was found in a study on secular trends in gestational age and birth weights in twins.

In this study twins registered at the NTR were compared with a national reference set. As a result of this positive selection bias, percentages of discordant triplets are probably underestimated compared to the total Dutch triplet population. The positive selection bias could also cause an underestimation of the percentage triplets that are classified as SGA.

We also do not know whether the effects of the investigated risk factors might be more pronounced in this more vulnerable group. We investigated whether zygosity influenced triplet BW. A more direct measure of triplets sharing placenta's and therefore triplet nutrients competition is chorionicity.

Information on chorionicity would therefore have been a valuable addition to the information on zygosity. Currently, no reliable information on chorionicity was available. Parity has been associated with BW but was not included in the analysis of present study, as information on parity was only available for about three-quarter of the mothers.

Including parity would therefore have decreased sample size considerably. In an analysis within the reduced sample, there was no significant effect parity on BW.

Some strengths of this study are also noteworthy. The sample is relatively large. We do not know of another study that took so many risk factors into account analyzing their effect on triplet BW. This study is the first to describe triplet zygosity in the Netherlands based on individual zygosity measures instead of population based estimated zygosity distribution.

Furthermore, this study is the first to investigate the effect of maternal smoking and alcohol consumption during pregnancy on triplet BW.

In addition, although our sample is somewhat positively biased when comparing it to all triplets born in the Netherlands, it is a representative sample for the Dutch triplet population that is still alive one month after birth. Longitudinal data collection on triplets is scarce. The data collection in triplets that we are currently establishing is unique in its kind.

With this dataset it is possible to study long term effects of low BW in triplets, both on physiologic and also on behavioral level. This study was limited to a description of the sex and zygosity distribution of the triplets and the effect of a number of BW characteristics.

We found an effect of GA, sex, birth order, zygosity and maternal smoking on triplet birth weight, but found no effect of ART and maternal alcohol consumption. The combined effects implied that differences of grams can be observed between MZ girl triplets of smoking mothers compared to TZ boy triplets of non-smoking mothers of the same GA. Furthermore, we found that MZ triplets resembled each other more than DZ triplets, indicating that, in addition to environmental factors, genetic factors contribute to triplet BW.

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Clin Obstet Gynecol. BMC Pregnancy Childbirth. Google Scholar. Blickstein I: Normal and abnormal growth of multiples. Semin Neonatol. Blickstein I: Is it normal for multiples to be smaller than singletons?.

Br Med J. Gynecol Obstet Invest. Early Hum Dev. Obstet Genecol. Am J Mel Genet A. Fertil Steril. J Obstet Gynaecol. Thandi Nxumalo 27 years old , who is a twin herself, also gave birth to triplets on the 16 February Nxumalo shares a backyard room with the unemployed father of three boys in Dobsonville, Soweto.

She named her offsprings Siyanda, Bayanda and Asanda. Both mothers started attending ante-natal care at local clinics when they were in advanced stages of pregnancy. They were diagnosed and referred to the hospital. Tags: Health Society. Newest first Oldest first. Read more More More. Switzerland records first over mothers This content was published on May 11, May 11, Switzerland is no exception to the late motherhood trend but the birth statistics have thrown up a new record — two first-time mothers aged Kids' art This content was published on Feb 26, Feb 26, Like many other museums, the Beyeler Foundation proposes children's activities.

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