I answered a sort of similar question here. In that post the gist about birthing practices among southern Northwest Coast (NWC) people was as follows:

Like virtually all other aspects of NWC culture, childbirth was rich with rituals and cultural conventions. There were dietary rules, residential rules and rules about travel for pregnant women. Special formulae of song, dance and medicine were used to assist with labor and other aspects of the actual birthing process. Activities around birth (e.g. naming conventions) were heavily constrained by rule and ritual. These kinds of norms surrounding birth are, in my experience, common among Native Americans and are just as likely to be noted for the Cherokee or the Powhatan as they are for NWC groups.

Given all these rituals and rules, it is not particularly surprising that there were special women that assisted in many of these women's practices. These women were usually from the extended family - often mothers, grandmothers, great aunts, or other relatives depending on kinship rules or a variety of other factors. Elderly, knowledgable women were respected and played an important role in the extended family/settlement. They conducted coming-of-age rituals for women. They carried and handed down spiritually powerful songs and dance formulae. They acted as advisors in matters of the family, marriage and decorum. And they played an important role in the preparation for, actual childbirth and follow-on related cultural practices.

More specific information on the actual childbirth among the Hupa, a Northwest California Athabascan group, is provided by Goddard:

If she was delivered at home she was taken to the mintc, where the elk-hide strap of the burden basket was hung up for her to pull upon, and a stick was placed between her teeth. She sat during labor. Some woman made for her the required medicine. For ten days she and the child remained in the mintc. The mother sat or lay over a pit in which heated rocks were covered with wet sand. It was thought that the steam assisted in healing any injured parts.

The mintc mentioned by Goddard is a shed or small structure used by women during menstruation or childbirth. The use of these specialized birthing/menstruation structures is very common among NWC groups.

Kroeber notes that among most California tribes sitting during childbirth was the norm. However, a Yurok woman is said:

to have lain bracing her feet against an assistant. Her hands were tied with pack straps to parts of the house frame. When the assistant commanded, she raised herself by these thongs.

In the far north, among the Haida, Tlingit and Tsimshian, birthing assistants were from the child's father's lineage. Among southern groups, assistants were not necessarily so aligned. This reflects the strong kinship and lineage rules of the far northern groups that are not as prevalent among the southern people.

Another difference noted between the northern and southern native people of the far west is the use of paid midwives. Kennedy and Bouchard note the use of hired midwives among the Northern Salish. Powell notes the same among the Quileute.

Sources:

Menstruation and the Power of Yurok Women: Methods in Cultural Reconstruction.Thomas Buckley American Ethnologist Vol. 9, No. 1 (Feb., 1982)

Life and Culture of the Hupa. P.E. Goddard UCPAAE Volume 1, 1903

Handbook of California Indians, A. L. Kroeber. San Francisco: Taylor and Taylor Press. 1970

Perdue, Theda, Cherokee Women: Gender and Culture Change, 1700-1835. Lincoln: University of Nebraska Press, 1998.

Rountree, Helen. Powhatan Indian Women: The People Capt. John Smith Barely Saw. Ethnohistory, 45 (1998) 1-29.

Quiliute. Powell, Jerome. In Handbook of North American Indians, Vol. 7 Northwest Coast. Smithsonian 1990

Northern Coast Salish. Kennedy, Dorothy and Randall Bouchard. In Handbook of North American Indians, Vol. 7 Northwest Coast. Smithsonian 1990