At 6 weeks pregnant, your baby’s major organs, brain, and spinal cord are actively forming, making this one of the most sensitive windows of development. What you eat, drink, apply to your skin, and expose yourself to matters more right now than at almost any other point in pregnancy. Here’s what to avoid and why.
Alcohol Has No Safe Threshold
There is no known safe amount of alcohol at any point during pregnancy, and the CDC is clear that this includes the earliest weeks, even before many people realize they’re pregnant. At 6 weeks, the neural tube is closing and facial structures are taking shape. Alcohol crosses the placenta freely and can interfere with this rapid development. If you’ve had a drink or two before finding out, that’s worth mentioning to your provider, but the guidance going forward is zero alcohol for the rest of pregnancy.
Medications to Pause or Avoid
Ibuprofen (Advil, Motrin) and naproxen (Aleve) are the big ones to stop. A large meta-analysis found that exposure to these anti-inflammatory painkillers in early pregnancy was linked to a 28% increased risk of congenital anomalies overall, including an elevated risk of heart defects. Acetaminophen (Tylenol) is generally considered the safer option for pain and fever during pregnancy, though you should still use it at the lowest effective dose.
Beyond over-the-counter painkillers, check with your provider before continuing any prescription medications, herbal supplements, or high-dose vitamins. Some acne medications, anti-anxiety drugs, and certain antibiotics carry risks during organogenesis, the period when organs are forming, which is exactly what’s happening at week 6.
Foods That Carry Real Risk
Pregnant people are 10 times more likely than the general population to get a Listeria infection, which can cause miscarriage even when the mother’s symptoms are mild. The highest-risk foods include unheated deli meats, cold cuts, and hot dogs; soft cheeses made from unpasteurized milk like brie, camembert, blue cheese, and queso fresco; and raw or undercooked sprouts. Heating deli meat until it’s steaming reduces the risk significantly.
Unwashed produce is another common source of both Listeria and Toxoplasma. Rinse all fruits and vegetables thoroughly under running water, even pre-bagged salad greens.
Raw or undercooked eggs and meat also pose a risk from Salmonella and Toxoplasma. Cook eggs until both yolk and white are firm, and use a meat thermometer to confirm poultry, beef, and pork reach safe internal temperatures.
Fish You Should Skip Entirely
Fish is actually recommended during pregnancy for its omega-3 content, but certain species accumulate dangerously high levels of mercury, which can damage a developing nervous system. The FDA lists seven types to avoid completely: shark, swordfish, king mackerel, marlin, orange roughy, bigeye tuna, and Gulf of Mexico tilefish.
Stick to lower-mercury options like salmon, shrimp, tilapia, and canned light tuna. The target is 8 to 12 ounces per week (two to three 4-ounce servings) from the FDA’s “Best Choices” list. Raw fish, including sushi made with raw seafood, also carries parasite and bacterial risks worth avoiding.
Caffeine: Stay Under 200 mg
You don’t need to quit coffee entirely. The American College of Obstetricians and Gynecologists considers moderate caffeine intake, defined as less than 200 mg per day, unlikely to be a major factor in miscarriage or preterm birth. That’s roughly one 12-ounce cup of brewed coffee. Keep in mind that caffeine also shows up in tea, chocolate, energy drinks, and some sodas, so the total adds up faster than you might expect.
Hot Tubs and Saunas
Raising your core body temperature above about 101.3°F (38.9°C) during the first trimester has been linked to neural tube defects. Hot tubs typically run between 100°F and 104°F, so even a short soak can push your internal temperature into that range. Research published in the Canadian Medical Association Journal found that prolonged use of hot tubs is more likely to raise body temperature to potentially harmful levels, though even brief sessions carry some risk during this critical developmental window. Warm baths are fine as long as the water isn’t hot enough to make your skin red or make you sweat.
Cat Litter and Garden Soil
Toxoplasmosis is a parasitic infection spread through cat feces, undercooked meat, and contaminated soil. Most people who catch it barely notice, but during pregnancy it can cause serious harm to the developing baby. If you have a cat, have someone else handle the litter box. If that’s not possible, wear disposable gloves and wash your hands thoroughly afterward. Change the litter daily, because the parasite doesn’t become infectious until one to five days after it’s shed.
The same parasite lives in garden soil and sandboxes where outdoor cats may have been. Wear gloves while gardening, and keep outdoor sandboxes covered. The FDA also recommends not adopting a new cat during pregnancy and keeping indoor cats inside.
Solvents and Strong Chemical Fumes
Paint thinners, turpentine, nail polish remover with toluene, industrial degreasers, and other organic solvents have been linked to miscarriage, low birth weight, preterm birth, and birth defects. Common solvents flagged by the CDC’s National Institute for Occupational Safety and Health include benzene, toluene, xylene, perchloroethylene (used in dry cleaning), and chloroform.
For everyday cleaning, well-ventilated use of standard household products like dish soap, diluted vinegar, or bathroom sprays is generally considered low-risk. The concern is concentrated, prolonged, or poorly ventilated exposure. If you’re planning a nursery renovation, let someone else handle paint stripping, staining, or anything that requires solvent-based products. Choose low-VOC paints and keep windows open.
Skincare Ingredients to Drop
Retinoids are the most important skincare ingredient to stop using. Oral retinoids (like isotretinoin for acne) are a well-established cause of severe birth defects. Topical retinoids, found in many anti-aging and acne creams labeled as retinol, tretinoin, or adapalene, absorb less into the bloodstream, but case reports of birth defects consistent with retinoid exposure exist. Until larger studies confirm safety, the guidance is to stop using them.
Hydroquinone, a skin-lightening ingredient, has a relatively high absorption rate of 35% to 45% through the skin and is best avoided. Most other topical skincare products, including sunscreens, gentle cleansers, and moisturizers, act locally and produce minimal systemic levels. Low-concentration salicylic acid in face washes (2% or less) is generally considered low-risk, though some providers recommend switching to glycolic acid as an alternative.
Exercise Adjustments
Exercise is encouraged during pregnancy, not discouraged. But at 6 weeks, it’s smart to start shifting away from activities with a high fall or collision risk. Contact sports like soccer, basketball, and martial arts, along with activities like horseback riding, downhill skiing, and gymnastics, carry the potential for abdominal trauma. Your center of gravity will shift as pregnancy progresses, making balance-dependent activities riskier over time.
ACOG recommends avoiding jerky, bouncy, or high-impact motions. Walking, swimming, stationary cycling, and prenatal yoga are all solid choices. If you were running or lifting weights before pregnancy, you can typically continue with modifications, but this is a good time to check in with your provider about your specific routine.
Smoking and Secondhand Smoke
Smoking restricts oxygen flow to the developing embryo and is linked to miscarriage, placental problems, preterm birth, and low birth weight. Vaping and e-cigarettes still deliver nicotine and other chemicals that affect fetal development. Secondhand smoke exposure carries its own risks, so ask household members to smoke outdoors and away from shared ventilation. If quitting feels overwhelming, your provider can discuss nicotine replacement options that are considered safer than continued smoking.