While within Tibetan Buddhism male monastics can upgrade their vows into the full ordination of a gelong (tibetan, sanskrit: biskhu), following the Mulasarvastavadin lineage observing 253 vows, this type of ordination never reached Tibet for women.
In the 1960s, The 16th Gyalwa Karmapa approached The 14th Dalai Lama on the subject, finding strong support by His Holiness to fulfill nuns’ aspirations. Succeedingly, the first nuns were sent to receive the vows within the Mahayana Buddhism, where the Dharmagupta lineage had been kept unbrokenly since the time of Buddha Shakyamuni with 348 vows to observe, mostly to Taiwan and Hongkong.
“[…] There are already nuns within the Tibetan tradition who have received the full Bhikshuni vow according to the Dharmagupta lineage and whom we recognize as fully ordained. One thing we could do is to translate the three primary monastic activities (Posadha, Varsa, Pravarana) from the Dharmagupta lineage into Tibetan and encourage the Tibetan Bhikshunis to do these practices as a Bhikshuni Sangha, immediately. […]” The Buddhist Bhikshu Tenzin Gyatso, The Dalai Lama
“The bikshuni ordination is not something that we don’t know how to conduct. But we don’t have the Bikshuni ordination lineage. So in order to make that possible my Guru, 16th Karmapa, sent Sister Palmo, Freda Bedi to receive the bikshuni ordination. That was more than 30 years ago. After his passing […] I kept on sending nuns to receive Bikshuni ordination so we can introduce this into our lineage. […] We have more than enough bikshunis. They started from the 1980s, now it is 2008. And not only that. They have done three months’ three years’ retreat. They are even lamas already. So they are bikshunis as well as lamas.” H. H. Guru Vajradhara Chamgon Kenting Tai Situpa, 2008
“Many people might think I’m doing this because others want me to. But I’m not doing it to placate anyone or in response to anyone. No matter how others see it, I feel this is something necessary. In order to uphold the Buddhist teachings it is necessary to have the fourfold community (fully ordained monks (gelongs), fully ordained nuns (gelongmas), and both male and female lay precept holders). As the Buddha said, the fourfold community are the four pillars of the Buddhist teachings. This is the reason why I’m taking interest in this.” (H. H. The 17th Gyalwang Karmapa, Orgyen Thrinley Dorje, January 2015)