Question: By 1973, how many women had served in  Vietnam?
About the article "Vietnam War", section "American nurses".

Candidate passages:
Women in the Vietnam War.
American nurses.
During the Vietnam War, American women served on active duty doing a variety of jobs.
Early in 1963, the Army Nurse Corps (ANC) launched Operation Nightingale, an intensive effort to recruit nurses to serve in Vietnam.
Most nurses who volunteered to serve in Vietnam came from predominantly working or middle-class families with histories of military service.
The majority of these women were white Catholics and Protestants.
Because the need for medical aid was great, many nurses underwent a concentrated four-month training program before being deployed to Vietnam in the ANC.
Due to the shortage of staff, nurses usually worked twelve-hour shifts, six days per week and often suffered from exhaustion.
First Lieutenant Sharon Lane was the only female military nurse to be killed by enemy gunfire during the war, on 8 June 1969.
At the start of the Vietnam War, it was commonly thought that American women had no place in the military.
Their traditional place had been in the domestic sphere, but with the war came opportunity for the expansion of gender roles.
In Vietnam, women held a variety of jobs which included operating complex data processing equipment and serving as stenographers.
Although a small number of women were assigned to combat zones, they were never allowed directly in the field of battle.
The women who served in the military were solely volunteers.
They faced a plethora of challenges, one of which was the relatively small number of female soldiers.
Living in a male-dominated environment created tensions between the sexes.
While this high male to female ratio was often uncomfortable for women, many men reported that having women in the field with them boosted their morale.
Although this was not the women's purpose, it was one positive result of the their service.
By 1973, approximately 7,500 women had served in Vietnam in the Southeast Asian theater.
In that same year, the military lifted the prohibition on women entering the armed forces.
American women serving in Vietnam were subject to societal stereotypes.
Many Americans either considered females serving in Vietnam masculine for living under the army discipline, or judged them to be women of questionable moral character who enlisted for the sole purpose of seducing men.
To address this problem, the ANC released advertisements portraying women in the ANC as "proper, professional and well protected."
(26) This effort to highlight the positive aspects of a nursing career reflected the ideas of second-wave feminism that occurred during the 1960s–1970s in the United States.
Although female military nurses lived in a heavily male environment, very few cases of sexual harassment were ever reported.
In 2008, by contrast, approximately one-third of women in the military felt that they had been sexually harassed compared with one-third of men.
During the Vietnam War, African-American servicemen had children with local Vietnamese women.
Some of these children were abandoned by the Vietnamese family, or sent to orphanages.
Many orphans and children were airlifted to adopting families in the United States in 1975 during "Operation Babylift" before the fall of South Vietnam.
The Afro-Vietnamese (or Afro-Amerasian) children suffered much discrimination in Vietnam at that time.
There was also some controversy as to how these orphaned Afro-Amerasian children were placed in new homes in the United States. 
The medal was awarded to all members of the New Zealand armed forces who, between 29 May 1964 and 27 January 1973, either:  served for 28 days, continuous or aggregated, in ships or craft employed in operations on inland waters or off the coast of Vietnam;  served for one day or more on the posted strength of a unit or formation on land in Vietnam;  conducted one operational sortie over Vietnam or Vietnamese waters by aircrew on the posted strength of a unit allocated for direct support of operations in Vietnam;  served for 30 days or more, continuous or aggregated, on official visits, inspections or other occurrences of a temporary nature on duty in Vietnam, or in ships or craft engaged in operations off the Vietnamese coast.
Service terminated by death or wounds, or the award of a decoration for gallantry, led to the immediate award of the medal, regardless of whether the qualification period had been fulfilled. 
From 1963 until 1973 50,000 Australian Army, Royal Australian Navy, and Royal Australian Air Force and associated personnel served in Vietnam in what was called the Vietnam War. 
The 17th Aviation Brigade is a military formation of the United States Army.
It was originally activated at Nha Trang, Vietnam, as the 17th Aviation Group (Combat) on 15 December 1965 under the 1st Aviation Brigade.
Later it moved to Tuy Hoa in November 1970 and then to Pleiku in January 1972.
The group had the mission of commanding and controlling all non-divisional assets in II Corps Tactical Zone, under I Field Force.
The 10th, 14th, 52d, 223d and 268th Aviation Battalions as well as the 7th Squadron, 17th Cavalry served with the group.
The following companies and detachments were also under the 17th Aviation Group: I Corps (Provisional), December 1965 – July 1966; expanded into the I Corps Aviation Battalion (Provisional) 57th Aviation Company (Assault Helicopter), April 1972 – March 1973; departed Vietnam 58th Aviation Detachment, October 1968 – January 1972; departed Vietnam 60th Aviation Company (Assault Helicopter), January 1972 – March 1973; departed Vietnam  129th Aviation Company (Assault Helicopter), April 1972 – March 1973; departed Vietnam 180th Aviation Company (Assault Support Helicopter), January 1972 – February 1972; transferred to the 7th Squadron, 17th Cavalry; second tour: April 1972 – February 1973; departed Vietnam 220th Aviation Company (Surveillance Light Aircraft), December 1965 – August 1966; transferred to I Corps Aviation Battalion (Provisional) 361st Aviation Company (Aerial Weapons), April 1972 – August 1972; departed Vietnam Troop H, 10th Cavalry (Air), April 1972 – February 1973; departed Vietnam.
Utilized assets of Troop C, 7th Squadron, 17th Cavalry Troop H, 17th Cavalry (Air), April 1972 – February 1973; departed Vietnam.
Utilized assets of Troop B, 7th Squadron, 17th Cavalry  Troop K, 17th Cavalry (Air), October 1970 – December 1970; departed Vietnam.
Utilized assets of Troop D, 7th Squadron, 17th Cavalry Source: "Vietnam Order of Battle" by Shelby L. Stanton.