I get this call at least a few times a week: “Dr. Rosie, my hens were laying beautifully and then just… stopped. What’s wrong with them?” Nine times out of ten, nothing is wrong exactly. Egg production is surprisingly sensitive to a long list of factors, and pinpointing the cause usually means working through a short checklist. Let’s go through every major culprit so you can figure out what’s happening in your flock.

1. Molting

Molting is the single most common reason healthy adult hens stop laying, and it catches new flock owners off guard every fall. Once a year — usually triggered by the shortening days of late summer or early autumn — hens shed their old feathers and grow a new set. The process diverts enormous amounts of protein away from egg production. A heavy molt can shut down laying entirely for 8 to 16 weeks.

You’ll know a molt is happening because your run will look like a feather pillow exploded. The birds themselves may look patchy, scraggly, or downright rough. This is completely normal.

What to do: Boost dietary protein to 18–20% (switch to a flock raiser or gamebird feed temporarily), keep stress low, and wait it out. Do not push them with artificial lighting during a molt — let their bodies complete the process. Laying will resume once the new plumage is fully in.

2. Reduced Daylight (Photoperiod)

Hens need roughly 14 to 16 hours of light per day to maintain peak egg production. As days shorten in fall and winter, many flocks slow down or stop laying entirely. This is a biological response, not a problem — it’s the hen’s way of conserving energy during the lean season. Some breeds (especially production Leghorns and other commercial-type layers) push through winter better than heritage breeds, but almost all hens are affected to some degree.

What to do: Add a simple 40–60 watt incandescent or LED bulb in the coop on a timer. Add light in the morning rather than the evening — abrupt darkness at night can disorient birds on the roost. Bring total light exposure to 14–16 hours and most hens will resume laying within 2 to 4 weeks. If you prefer a natural winter break, that’s completely valid too — many flock owners appreciate the built-in rest period.

3. Age

A hen is born with all the egg follicles she will ever have. Production peaks in year one, remains strong in year two, and begins a gradual decline from year three onward. By year four or five, many hens are laying half or fewer of what they did at peak. Older hens don’t stop suddenly — they taper.

What to do: Manage your expectations and plan for flock succession. If you’re counting on a steady supply of eggs, stagger the ages in your flock by adding young pullets every year or two. Older hens still have real value — they’re experienced, calm, and great at establishing flock order for newcomers.

4. Stress

Chickens are more sensitive to stress than most people realize. A predator circling the coop at night, a new flock member being integrated, a dog charging the run, construction noise nearby, extreme weather — any of these can cause hens to stop laying for days to weeks. I’ve seen flocks go silent after a single raccoon scare.

What to do: Walk your property at dusk and look for predator evidence (tracks, scat, bent hardware cloth). Secure the coop properly — hardware cloth instead of chicken wire, locks on doors, no gaps at the roofline. Give new flock introductions time (the standard “see but don’t touch” quarantine period is 30 days, and integration should be gradual). Remove obvious stressors and give the flock a few quiet, consistent weeks to recover.

5. Poor Nutrition

An egg is roughly 70% water and 30% protein and minerals. Hens physically cannot produce eggs without adequate calcium and protein. I see nutritional laying slumps frequently, and they’re almost always caused by one of three things: feeding scratch grains as a primary diet (scratch is junk food for chickens, not a complete feed), running out of layer feed and substituting something else, or not offering free-choice oyster shell.

  • Calcium deficiency: Thin-shelled or shell-less eggs first, then production drops. Fix: always offer free-choice oyster shell alongside layer feed. Do not add it to the feed itself — let hens self-regulate.
  • Protein deficiency: Production drops, feathering looks poor. Fix: switch to a quality layer feed with at least 16% protein. Limit scratch to no more than 10% of total diet.
  • Fresh water: This one surprises people. A hen who can’t access clean, unfrozen water for even a few hours will stop laying. Check waterers daily, especially in freezing temperatures.

6. Broodiness

A broody hen has decided she wants to hatch eggs. She’ll sit on the nest all day (and night), puff up aggressively if you reach under her, and stop laying entirely while she’s in this state. Broody behavior is hormonally driven and can last 3 to 8 weeks if left unchecked. Some breeds — Silkies, Cochins, Orpingtons — are notoriously broody. Production breeds like Leghorns almost never go broody.

What to do: If you want to hatch chicks, let her sit on fertilized eggs. If not, break the broodiness: remove her from the nest repeatedly, block access to the nest box, or place her in a wire-bottomed “cooler cage” with food and water for 3 to 5 days. The airflow under the wire helps drop her body temperature, which resets the hormonal cycle. She should resume laying within 1 to 2 weeks of breaking the brood.

7. Illness or Parasites

Sick hens stop laying. This is one of the most important things to understand about poultry health — egg production is the first thing the body sacrifices when it’s fighting an infection or parasite burden. If the other causes on this list don’t fit your situation, illness belongs in the differential.

Common culprits include respiratory infections (infectious bronchitis is a classic layer-stopper), Marek’s disease, infectious laryngotracheitis, and heavy mite or lice infestations. External parasites are dramatically underdiagnosed — check under the wings and around the vent for moving specks (mites) or nits attached to feather shafts (lice). A heavy red mite infestation in the coop can cause significant anemia in hens without owners ever seeing it.

What to do: Isolate any hen that looks ill (dull, fluffed, eyes closed, nasal discharge, labored breathing). Contact a poultry-experienced vet. Treat mite and lice infestations promptly with permethrin-based products approved for poultry, and treat both the birds and the coop simultaneously.

8. Extreme Temperatures

Both heat and cold suppress laying. In summer, when temperatures climb above 85°F (29°C), hens begin diverting energy to thermoregulation and production drops. Above 95°F (35°C), it can stop entirely — and heat stress becomes a veterinary emergency. In winter, cold itself doesn’t stop laying as much as the reduced daylight does, but an unheated coop in a brutal winter will slow things down regardless.

What to do: In summer: shade, ventilation, and cold water are your best tools. Frozen treats (watermelon, ice blocks with vegetables) help birds cool down. In winter: insulate the coop but prioritize ventilation over warmth — moisture and ammonia buildup from poor ventilation cause respiratory disease. A dry, well-ventilated coop at 35°F is healthier than a warm, damp one at 50°F.

The Bottom Line

Here’s what I tell my clients at the end of every troubleshooting conversation: laying slumps are almost always temporary, and the cause is almost always fixable. Work through the list systematically — check daylight, check feed, check for stress triggers, check for parasites — and you’ll almost always find your answer without a vet visit. The cases that genuinely worry me are hens who look sick alongside the laying drop, or flocks where multiple birds go downhill at once. That’s when you want a professional set of eyes. For a hen who’s acting completely normal but just not laying, be patient. Your eggs are coming back.