structural:summarization, information:filtering
Health problems

According to the New York Times' Jane E. Brody, in September 1982, an acute attack of toxoplasmosis "contributed to Martina Navratilova's defeat during the US Open tournament ", in which No. 1 seed Navratilova unexpectedly lost to No. 7 seed Pam Shriver in the quarterfinal round. By late October, Navratilova had "apparently recovered".

Navratilova began to wear glasses in 1985 and recalled that her vision had begun to deteriorate in 1984. She continued to wear glasses for tennis for many years. Few tennis players wear sunglasses regularly for tennis and Navratilova is one of them. Although she achieved so much prior to using glasses, her glasses have become iconic. Some sports writers have said that they made her, as with other top athletes who had imperfect health, seem more vulnerable and human.

On April 7, 2010, Navratilova announced that she was being treated for breast cancer. A routine mammogram in January 2010 revealed that she had a ductal carcinoma in situ in her left breast, which she was informed of on February 24, and in March she had the tumour surgically removed; she received radiation therapy in May.

In December 2010, Navratilova was hospitalized after developing high altitude pulmonary edema while attempting a climb of Mount Kilimanjaro in Tanzania.

In January 2023, Navratilova was diagnosed with both throat (stage one) and breast cancer. This came after Navratilova discovered a swollen lymph node on her neck, leading her to take medical tests. In March 2023 and after more preventive radiation, she stated that she was cancer-free.