Human Immunodeficiency Virus (HIV) and NIH Women's Health Research

Signs, Symptoms, and Risk Factors

HIV is a virus that damages the immune system by attacking CD4+ T lymphocytes. HIV is transmitted through certain bodily fluids, including blood, semen and other genital secretions, and breastmilk.

Early symptomatic (acute) HIV infection typically develops within 2 to 4 weeks after acquisition and may cause flu‑like symptoms, although most people have few or no symptoms and the infection goes unnoticed. Because these symptoms are nonspecific, when symptoms occur, they are often mistaken for other viral illnesses. Following the acute stage, individuals enter a chronic stage, during which many have no symptoms for a period that can last from months to years. Without treatment, HIV continues to damage the immune system over time¹ and can advance to acquired immunodeficiency syndrome (AIDS).² People with AIDS are vulnerable to opportunistic infections, such as tuberculosis and Pneumocystis pneumonia, and to certain types of cancer, including cervical cancer.³

Impact on Women's Health

Women face unique risks for HIV because of both biological and social factors. Biologically, the lining of the vagina is more exposed during sex, making it easier for the virus to enter the body compared with other types of sexual exposure. Conditions such as sexually transmitted infections, bacterial vaginosis, or age-related vaginal dryness can cause small tears in the vaginal tissue, further increasing vulnerability.⁴ In addition, gender power dynamics and limited ability to negotiate condom use can increase women's risk of exposure to HIV.⁵ HIV also has important implications for women's reproductive health: it can affect fertility, increase the risk of complications during pregnancy, and, if untreated, can be passed to the baby during pregnancy, delivery, or breastfeeding.⁴

Diagnosis and Treatment

HIV testing allows for the diagnosis of infection. An estimated 15% of people with HIV in the United States are unaware they have HIV, and about 40% of new HIV infections are transmitted by people who are not aware of their HIV status.⁶ HIV testing is very important for all women, including those who feel healthy. Early diagnosis allows women to start treatment right away, and today's treatments are highly effective at helping women live long, healthy lives and preventing the progression to AIDS. Although HIV currently has no cure, adhering to a treatment regimen that includes antiretroviral therapy is highly effective against HIV.⁷ Starting treatment early also protects reproductive health, reduces the risk of complications in pregnancy, and nearly eliminates the chance of passing HIV to a partner or a baby.⁸

Ongoing Research

Putting women at the center of HIV research is essential to better understand their needs and to develop care and prevention strategies that protect their health and future. Future research is needed to better characterize the interactions between antiretroviral drugs and hormonal therapies, including hormonal contraceptives and menopausal hormone therapy, and to evaluate the long-term health effects of antiretroviral therapy in women with HIV.⁹

The Office of AIDS Research (OAR) and Office of Research on Women's Health (ORWH) are collaborating on the HIV and Women Signature Program, which launched in February 2023. The program advances an intersectional and data-driven approach to researching HIV and the health of women and girls, particularly those who remain disproportionately affected by HIV, including women of color and young women. As a cornerstone of this effort, OAR and ORWH convened an NIH-wide HIV and Women Working Group to identify research gaps and priorities at the intersection of HIV and women's health, with a strong emphasis on sex as a biological variable and inclusive research design. The program is further informed by portfolio analyses, scientific workshops, and targeted funding opportunities aimed at strengthening evidence-based HIV prevention, treatment, and care tailored to women's unique needs and circumstances.