Causes & Complications of Multiple Births

Cigarette smokingCigarette Smokecomprises a highly complex chemical mixture of non-specific products of organic material combustion, (such as acetaldehyde and formaldehyde) and chemicals that are specific to the combustion of tobacco and other components of the cigarette (e.g. tobaccospecific nitrosamines)over 4000 chemical constituents in tobacco smoke (British Columbia Ministry of Health)Polycyclic Aromatic Hydrocarbons (PAHs)CHEMICAL CHARACTERISTICSlarge group of organic compounds with two or more fused aromatic (benzene) rings with a pair of carbon atoms shared between rings in their moleculeshigh melting and boiling points low vapor pressure, very low aqueous solubilityhighly lipophilic and therefore very soluble in organic solvent

*Causes mutation in the genes and damage to DNA

NICOTINERecent studies indicate that smoking/nicotine increases maternal blood pressure and decrease in uterine blood flow in pregnancy.>However, the mechanisms are not fully understood. (Xiao, 2011)types

Causes & Complications of Multiple Births9Multiple Birth FactsChance of havingTwins: 1:80Triplets: 1:6400Conjoined or Siamese: 1:50000 chance, about half are still-born.

Multiple births have ahigher mortality rate.

10Naturally Occurring Ways of Increasing the Chance of Multiple BirthsHeredityA family history of multiple pregnancy increases the chances of having twins.Older AgeWomen over 30 have a greater chance of a multiple birth. Multiple births more common due to today's increase in the number of births later in women's lives.High ParityHaving one or more previous multiple pregnancies increases the chances of having multiples.RaceAfrican-American women are more likely to have twins than any other race.Caucasian women, especially those over age 35, have the highest rate of higher-order multiple births (triplets, quadruplets etc.).11Unnatural Methods in Increasing the Chance of Multiple BirthsHelp produce many eggs, which if fertilized, canresult in multiple births.

Allows multiple eggs to be fertilised & then returned to the uterus to develop.12How Multiple Births Occurs: Fraternal Twinning13How Multiple Births Occurs: Identical Twinning14Identical Vs. Fraternal Twinning

15Medical ComplicationsPreterm LabourNearly half of all twins or higher-order multiples are premature births (born before 37 weeks) The higher the number of fetuses in the pregnancy=greater risk of early birthPremature babies: born before body & organs have not fully maturedThey are small & may need help breathing, eating, fighting infection, & staying warm

16Medical ComplicationsBirth DefectsMultiple birth babies have about twice the risk of congenital abnormalities including neural tube defects and heart abnormalities.

MiscarriageMore likely in multiple pregnanciesMore than one fetus is diagnosed, but vanishes (or is miscarried), usually in the first trimester (three months)Sometimes accompanied by bleeding. The risk of pregnancy loss is increased in later trimesters as well.17

Medical ComplicationsTwin-to-Twin Transfusion SyndromeCondition of the placentaOnly develops with identical twins that share a placentaBlood vessels are connected within the placenta and divert blood from one fetus to the other Occurs in about 1 in 7 twins with a shared placenta18Medical ComplicationsAbnormal Amounts of Amniotic FluidMore common in multiple pregnancies, especially for twins that share a placenta

Caesarean DeliveryAbnormal fetal positions increases chances of caesarean birth

Postpartum HaemorrhageIn many multiple pregnancies; the large placental area places mother at risk of bleeding after delivery.

19Non-Medicinal ComplicationsMany mothers of multiple births find breast-feeding their babies difficult. Different diets and lifestyles are required to produce enough breast-milk for the multiple babies.

Severe lack of sleep is a common problem with a single child, but with multiple births, many parents require respite programs to help with the difficult situation.

20mechanismMechanismresults from the ovulation and subsequent fertilization of more than one oocyte-the fetuses are genetically different (polyzygotic or non-identical)

from the splitting of one embryonic mass to form two or more genetically identical fetuses (monozygotic)