Kusenokwenzeka ukuba uye wakuva malunga "nempembelelo yamathambo," ulungelelaniso phakathi kokuthatha iipilisi zokulawula ukuzala nokuguqa. Kucatshulwa ukuba xa ukhulelwe emva nje kokuyeka ukusebenzisa iipilisi zokulawula ukuzala, amathuba akho okuba namawele akhula. Ngethuba usebenzisa iipilisi zokulawula ukuzala, i- ovulation igxothwa. Xa bekekile, bacinga ukuba ii-ovari zingaphinduka kwaye zenze i-superovulate, ikhuphe ngaphezu kweqanda elilodwa kumjikelezo kunye nokwandisa ithuba lokukhulelwa i- dizygotic okanye iwele.
Ukuqhagamshelana phakathi kweTyunning and Birth Control Pills
Le ngcamango isekelwe kwisifundo se-1977 esapapashwa kwi- New England Journal of Medicine esibonisa ukuba abasetyhini abakhulelwe kungekudala emva kokuyeka izithintelo zokukhulelwa komlomo babedla kabini ukuba babe namawele. Lawa mawele aqhelekileyo adizygotic (abazalwana), kunokuba i-monozygotic (ifanayo).
Ifom ye-Dizygotic ifom xa amaqanda amabini ahlukeneyo ehlanjululwa ngamabini ahlukeneyo, exhasa imbono yokuba ii-ovari zikhulula amaqanda amaninzi ekuphenduleni ukuyeka iipilisi zokukhulelwa. Ngokwolu cwaningo, emva kokuphuma kwipilisi kwiinyanga eziliqela, i-ovulation kufuneka ibuyele kumzekelo oqhelekileyo weqanda elinye ngenyanga, kwaye amathuba okuba amawele ancitshiswe kumazinga aqhelekileyo.
Uphando luxubile
I-"effect twins" ayizange iphandwa yonke into ukususela ngo-1977 isifundo kwiNew England Journal of Medicine, kwaye yintoni uphando oluthile luye lwaxutyushwa.
Ngomnye u-1989 uphando wenza ukuba ukukhulelwa ngaphakathi konyaka emva kokuba uthathe i-contraceptive ngomlomo kwandise amathuba akho okufumana amawele e-monozygotic (afanayo). Kanti olunye uphando olukhulu ngo-1987 alubonisi ukuhlangana phakathi kwamawele kunye nokuthatha izithintelo zomlomo.
Ngama-anecdotally, amaninzi amama amawele athetha ukukhulelwa kungekudala emva kokuyeka iipilisi zokulawula ukuzalwa njengesizathu sokuba bekhulelwe ngamawele.
Ezinye Iingxaki Zamawele Obazalwana
Kukho izizathu ezininzi zokuba kutheni ungakhulelwa ngamawele omzalwana, kuquka:
- I-Genetics : Abanye abesifazana banokuthi bahlaziye rhoqo kwaye kubonakala kunomdla , okanye mhlawumbi izakhi zofuzo ezininzi, ezibangela ukuba benze njalo. Nangona bobabini abesilisa nabesifazana bephethe i-gene, abafazi kuphela bahamba, ngoko ke umfazi ophethe i-gene ochaphazela i-ovulates angaba namawele. Indoda ene-gene yayingeke ikwazi ukuba namawele, kodwa ingadlulisela impawu kwintombi yakhe, mhlawumbi ibe ngumviwa ukuba abe namawele. Ukubeka nje, umfazi unokufumana ilifa elifanelekileyo ukuvelisa iqanda elilodwa kunina okanye uyise okanye kubazali bobabini.
- Imbali yentsapho: Abasetyhini abaye bazalela kwaye bazala abantwana abaninzi sele benokuba namathuba amawele. Nangona ukukhulelwa kwangaphambili akubanga i-hyperovulation okanye kubangele amawele, kunokwenzeka ukuba isibeleko sikamama sisisigxina kakhulu sokugcina ukukhulelwa kwamawele.
- Iminyaka yobudala: Njengokuba umfazi ekhula, unako ukuvelisa iqanda elinye ngexesha. Oku kusenokuba ngumzamo wokukhawuleza ukuvelisa ngaphambi kokuba ixesha liphume. Abasetyhini abangaphezu kweminyaka engama-30 banamathuba okuba namawele, kwaye isantya sanda nangaphezulu emva kweminyaka engama-35.
- Isisombululo sokuphakama kunye nomzimba (BMI) : Abafazi abakhulu banomlinganiselo ophezulu kunamaqondo aphezulu okukhulelwa. Izizathu azikodwa ngokukodwa, kodwa mhlawumbi kuba kukuphakama ukuphakama kunxulumene nesondlo esingcono, okanye ukuphakama okongeziweyo kunika ikamelo elithile kwisibeleko, ukwenza ukuba ukhulelwe ngokubanzi kunokwenzeka ukuba kukhule. Abasetyhini abane-BMI ye-30 okanye ngaphezulu bangaphezu kwamanqanaba amaqondo ukuba babe namawele, ngoxa abafazi abane-BMI abangaphantsi kwe-20 banamathuba amaninzi.
- Uhlanga : Abafazi baseAfrika bavelisa inani eliphakamileyo lamamawele angaphezu kwamabhinqa aseAsia.
- Ukutshaya : Ukuba utshaya, unokuba nomngcipheko ophezulu wokuba namawele, kodwa izifundo zilinganiselwe kule mlinganiso.
> Imithombo:
> Campbell D, Thompson B, Pritchard C, iSamphier M. Ngaba Ukusetyenziswa koNyango wokuNyulwa komlomo kuCinezela i-Twinning Rates? I-Acta geneticae medicae ne-gemellologiae: uphando lweefa . 1987; 36 (3): 409-415. i-doi: 10.1017 / S0001566000006176.
> Hoekstra C, Zhao ZZ, Lambalk CB, et al. Dizygotic Twinning. Ukuhlaziywa koLuntu. NgoJanuwari 1, 2008; 14 (1): 37-47. i-doi: 10.1093 / i-humupd / dmm036.
> Murphy MF, Campbell MJ, Bone M. Ngaba kukho Ingozi eyongezelelekileyo yokuqhawula emva kokunqunyulwa kwePill pilice? Umbhalo we-Epidemiology kunye neMpilo yoluntu . 1989; 43 (3): 275-279.
> Rothman K. Fetal Loss, Ukuhlambalaza kunye nobunzima bokuzalwa emva komlomo-Usetyenziso lokukhusela. NEJM , Septemba 1, 1977; 297: 468-471. i-doi: 10.1056 / NEJM197709012970903.