Njira ya kalendala yotetezera ku mimba inakhazikitsidwa m'ma 1920 ndi katswiri wa amayi a ku Japan Ogino ndi Austrian Knaus. Njirayi ikukhazikitsidwa powerengera tsiku loti chidziwitso chidziwitse ndi kudziletsa kugonana m'masiku abwino kwambiri okhudzana ndi mimba. Njira ya kalendala ndi imodzi mwa osakhulupirika kwambiri. Kuyambira 9 mpaka 40% azimayi omwe amagwiritsa ntchito njirayi amakhala ndi pakati. Choncho, njira yodzitetezera yapamwamba kwambiri inakhazikitsidwa - njira yodabwitsa. Kuwonjezera pa kuwerengera tsiku la ovulation, limaganizira momwe thupi limakhalira.
Njira ya kalendala ya Ogino-Knows
Njira iyi ndiyo njira yowonjezera yodzitetezera. Icho chimazikidwa pazowona ndi kuwerengera. Chifukwa chazomwe sizingasokonezedwe mu chilengedwe cha thupi, njira ya kalendala ndiyo njira yokhayo yotetezera yomwe ikuvomerezedwa ndi Tchalitchi cha Roma Katolika.
Chofunika cha njirayi ndi chonchi. Pambuyo pa kugonana mukazi, spermatozoa amakhala ndi maola angapo chabe. Ndipo kufika pachibelekero amakhala akugwira ntchito kuyambira masiku awiri mpaka sabata. Ovom mu ovulation (kuchoka ku ovary) ikhoza kumangidwira mu maola 24 okha. Podziwa chiyambi cha mavuni, mungathe kukonzekera kuchita zogonana kuti ngakhale asamalole kutenga mimba yosafuna. Kuti mugwiritse ntchito kalendala ya Ogino-Knaus mosamala, m'pofunika kudzaza kalendala ya kusamba kwa chaka chonse. Komabe, njira iyi ndi yoyenera kwa amayi omwe ali ndi msambo wokhazikika. Kulephera kochepa pang'ono mu machitidwe a mahomoni, matenda, mantha amantha amatha kusinthanso msambo ndipo amachititsa zolakwika muziwerengero. Ndipo, chifukwa chake - kutenga mimba.
Mwa njira ya Ogino-Knaus, mukhoza kuwerengera "masiku oopsa" (oyenerera kutenga pakati):
- Chiyambi cha nthawi yoopsa (chonde) chimawerengedwa ndi chiganizo: Kutalika kwa nthawi yayifupi ndi masiku 18;
- Mapeto a nyengo yowonjezera amawerengedwa ndi ndondomekoyi: Kutalika kwa ulendo wautali ndi masiku khumi ndi awiri.
Mwachitsanzo, poyang'ana miyezi 12 yapitayi, munawerengetsa kuti ulendo wamfupi kwambiri unali masiku 26, ndipo motalika kwambiri anali masiku 32. Zikuoneka kuti kuyambira masiku 8 (26-18) mpaka masiku 21 (32-11) a ulendowo (ndipo tsiku loyambalo likutengedwa kuti ndilo tsiku loyamba la kusamba) ndilo lovomerezeka kwambiri pa kutenga pakati. Ngati cholinga chake ndi kukhala otetezeka kuchokera mimba, ndiye kuti masiku ano ndi kofunikira kuti mupewe kugonana, kapena kutetezedwa m'njira zina. Ndipo mosiyana, kuyambira masiku 1 mpaka 8, komanso kuyambira masiku 21 mpaka kumapeto kwa njirayi, njira iyi sungatetezedwe.
Kuti muteteze njira iyi si yabwino. Koma pakukonzekera kwa mimba njira iyi ndi yothandiza kwambiri.
Njira ya kalendala yamaganizo
Zimadziwika kuti pamapeto a masiku a 28, ovulation amapezeka tsiku lachisanu ndi chiwiri la kusamba. Koma ichi ndi mtengo wapatali. Kwa amayi ambiri, kuzungulirako kumakhala kosiyana, ndipo kutsegula kwa ovulation kumachitika kanthawi kapitako kapenanso pang'ono. Poganizira zofooka za chitetezo ku Ogino-Knaus, akatswiri adalimbikitsa kuwonjezera tsiku la ovulation kalendala ndi magawo atatu ena. Choyamba ndi kuyendetsa kutentha kwa thupi (njira ya kutentha). Chachiwiri ndi ulamuliro wa chiberekero cha khomo lachiberekero chobisika kuchokera ku chiberekero (njira yachiberekero). Gawo lachitatu ndilo kusintha kwa chikhalidwe cha chiberekero, kufatsa kwake ndi kutsegula. Zotsatira za zochitika zonsezi zalembedwa mu kalendala yapadera, malinga ndi zomwe masiku otetezeka ogonana amatsimikiziridwa.
Mphamvu ya kalendala yamakono ndi yodabwitsa kwambiri. Ndi chachiwiri kukwaniritsa kuperewera kwa madzi. Ndi kugwiritsa ntchito bwino, amayi atatu okha mwa 1000 ali ndi mimba yosakonzekera (0.3%!). Izi zikufanana ndi njira ya mahomoni komanso yapamwamba kwambiri kuposa njira zina zogwirira ntchito. Komabe, njirayi siziteteza ku matenda opatsirana pogonana. Kuti mugwiritse ntchito njira yodalirika, ndikofunikira kuyang'anira matenda anu tsiku ndi tsiku. Zomwe zimachitika zimatengera pafupifupi 10 mphindi patsiku. Njira yoyamba ikuwoneka yovuta ndipo isanayambe ikulimbikitsidwa kuti iphunzitsidwe bwino.