Cockroaches do not lay loose eggs. They produce a brown, purse-shaped capsule called an ootheca. A German cockroach ootheca holds 30 to 48 eggs, and the female carries it until the eggs nearly hatch, so survival is high. Empty capsules are a sign of infestation.
If you have found small brown, seed-like cases in a kitchen cabinet or behind an appliance, you are almost certainly looking at cockroach eggs, or more precisely the capsule that holds them. Cockroaches do not scatter individual eggs the way many insects do. Instead, the eggs are packaged inside a hardened case called an ootheca. Reading that capsule correctly tells you what species you have, whether the eggs have hatched, and how urgent the problem is. The species that matters most indoors is the German cockroach, which is nearly always the roach found in kitchens and apartments because it reproduces faster than any other house-infesting species.
A single cockroach egg is tiny and is never really seen on its own. What you find is the ootheca: a brown, purse-shaped egg capsule that looks a bit like a small bean or wallet. Inside, the eggs are lined up in neat rows. For the German cockroach, this capsule is the key to identification, because the female carries it attached to the tip of her abdomen until the eggs are almost ready to hatch. Keeping the capsule with her, tucked into tight cracks and crevices, shelters the eggs and drives up their survival rate.
The most useful clue for a homeowner is an empty capsule. Once the young hatch, the spent brown case is left behind in drawers, seams, and hidden corners. Finding these empty oothecae means eggs have already hatched and roaches are breeding on-site, which is a recognized sign of an established infestation. Where you find capsules, you will often find baby cockroaches nearby, since the nymphs stay close to the same warm, hidden harborage.
The German cockroach is a reproductive powerhouse, and the numbers explain why an infestation can escalate so quickly. Each ootheca holds 30 to 48 eggs, and a single female produces 4 to 8 capsules over her lifetime, roughly one every 6 weeks. The eggs then spend 14 to 35 days in the capsule before hatching. Because the female carries the capsule until it is nearly ready to hatch, the eggs are protected during that whole window, which is a major reason the species out-breeds every other house roach.
The hardened ootheca is built to protect the eggs, and it does its job well: the capsule resists many contact insecticides, so a spray that kills adults on the surface often fails to reach the eggs inside. That is why spraying alone rarely clears an infestation. The reliable strategy is what pest professionals call a Bait-and-Sanitation approach, an integrated pest management method that targets the roaches carrying and hatching those capsules rather than the shells themselves.
Two pillars do the work. First, bait gels placed at hiding spots are eaten by roaches and carried back through the population, reaching the breeding insects that produce the capsules. Common active ingredients include hydramethylnon, fipronil, and boric acid, the last of which works slowly but reliably and does not trigger an escape reaction. Second, sanitation removes the food and water roaches need and seals the cracks where capsules are sheltered, starving the population and exposing hidden harborage.
For a full room-by-room plan, see how to get rid of cockroaches, and read more about the species behind most indoor egg cases in the cockroaches overview.