Traumatic Insemination - Health Repercussions

Health Repercussions

While advantageous to the reproductive success of the individual male, traumatic insemination imposes a cost on females: reduced lifespan and decreased reproductive output. "These include (i) repair of the wound, (ii) leakage of blood, (iii) increased risk of infection through the puncture wound, and (iv) immune defence against sperm or accessory gland fluids that are introduced directly into the blood."

The male bed bug penis has been shown to carry five (human) pathogenic microbes, and the exoskeleton of female bed bugs nine, including Penicillium chrysogenum, Staphylococcus saprophyticus, Stenotrophomonas maltophilia, Bacillus licheniformis, and Micrococcus luteus. Tests with blood agar have shown some of these species can survive in vivo. This suggests infections from these species may contribute to the increased mortality rate in bed bugs due to traumatic insemination.

The successive woundings each require energy to heal, leaving less energy available for other activities. Also, the wounds provide a possible point of infection which can reduce the female's lifespan. Once in the hemolymph, the sperm and ejaculatory fluids may act as antigens, triggering an immune reaction.

There is a tendency for dense colonies of bed bugs kept in laboratories to go extinct, starting with adult females. In such an environment, where mating occurs frequently, this high rate of adult female mortality suggests traumatic insemination is very detrimental to the female's health. The damage done, and the (unnecessarily) high mating rate of captive bed bugs, have been shown to cause a 25% higher-than-necessary mortality rate for females.