Vatsvakurudzi veAmerica vakasvika pakugumisa kuti vana vakaberekwa vasati vasvika, kazhinji kacho gare gare, vanoramba vasina vana
Iyi mhedziso yakazosvika nevemasayendisiti veAmerica avo vakazotevera kuguma kwevanhu vane mamiriyoni 1.2 vakazvarwa muNorway kubvira muna 1967 kusvikira muna 1988. Maererano nevatsvakurudzi vanobva kuMudy Center Centre kuDuke University, vana vanenge 60 000 vakaberekerwa panguva ino vakaberekwa vasati vasvika. Gare gare vakomana, avo vakaberekerwa vhiki 28-32. vakanga vachiva vanababa makumi matatu kubva muzana pane zvishoma pane avo vakazvarwa panguva. Pakuberekwa kwemazuva mashomanana ekuzvitakura, njodzi yekushaya vana yakawedzera, Geeta Swami, mutungamiri wekudzidza, akaiswa pachena. Vakomana vakaberekwa vhiki 22-27. pamuviri, vakawana vana vavo nevana 76% vashoma pane avo vakaberekerwa mumasvondo 37-40. Uye vasikana vakaberekerwa musi uyu havana kuberekwa ne 67% kakawanda pane avo vakazvarwa panguva.