Frida was unable to bear any children due to the terrible bus accident happened in the summer of 1926 when she was only 18 years old. Since then her obsession with fertility was often the subject of her paintings.
In this painting, the sun is surrounded by plants. It implies the sun is giving life to the plants and the plants mimics the shape of male penises and female wombs. Together they are protecting a growing fetus inside. Both the sun and the fetus are crying. This might be an implication of her won sadness over the infertility.