You spent nine months worrying about how what you eat, drink, or wear might affect your baby. Now that she's here you worry about whether or not something will contaminate your breast milk. We've come up with a list of some of your most common worries and let you know what's safe, and what isn't.

Always consult your doctor if you have any questions or concerns--this is not medical advice.

1. Medications

If you have a minor ache or pain, or something more severe like postpartum depression, there is a high likelihood that you will want or need to take medication during your time as a breastfeeding mom. While many doctors and pharmacists are aware of contraindications for certain medications, ask them to review the National Institute of Health’s monthly-updated website, LactMed.

Many medications that were previously thought to be dangerous during breastfeeding have been shown to be safer than originally thought. Always check with your physician before starting or stopping any medication.

2. Alcohol

You've gone nine or more months without having a drink. Now that baby is here, is it safe to drink again?

Outdated advice says that it’s safe to drink as long as you “pump and dump” for 24 hours after drinking—but new studies show that’s a waste of time, effort, and “liquid gold.” According to sources at kellymom.com, only about 2% of what you drink makes it into breast milk. If you’re no longer feeling the effects of what you’ve imbibed, you’re good to go--many experts say to wait three hours after one drink.

3. Vaccines

Vaccinations are an easy and relatively safe way to avoid infection from many potentially lethal diseases. Vaccines work by stimulating your immune system to create antibodies and cause immunity. Although antibodies do cross into breast milk, your milk does not provide levels high enough to give your baby immunity, too.<br><br>While most vaccines appear to be safe for nursing mothers and their babies, if you are planning to travel and need to be vaccinated against Yellow Fever and/or Smallpox, discuss these vaccines with your doctor. According to the The CDC, they are the only two vaccines not on an approved list.

4. Anesthesia

As more studies are being done to determine exactly how much of what you consume enters your breast milk, information is coming out stating that not as much goes into your supply as previously thought.

Conventionally, doctors and nurses have recommended waiting at least 24 hours to resume nursing, and dumping anything you have pumped. The U.S. Department of Health and Human Services now states that with many anesthetics, as long as your baby is healthy, it’s OK to resume nursing once you are awake and alert enough to hold your baby.

5. Exercise

Exercise is a good way to alleviate stress while helping your body return to its pre-pregnancy state. While there are no restrictions on what exercise you can do while breastfeeding, you will have to keep a closer watch on your water intake. Dehydration is one of the easiest ways to lose your milk supply.

If you are going to be running, bouncing, or putting any pressure on your chest, you should also consider doubling up on breast pads to avoid any troublesome leaks.

6. Marijuana

Marijuana is slowly becoming legal in some states and decriminalized in others. In 2001 a study from the American Academy of Pediatrics listed Marijuana as a drug for which the effects of transference in breast milk are unknown but may be cause for concern.

Potential effects on a breastfed infant exposed to marijuana-tainted milk may include delayed motor development, weakness, sedation, and poor feeding. Skip it.

7. Nicotine

Whether you nurse your child or formula-feed, the biggest danger from cigarettes is the exposure to secondhand smoke. If you or anyone in your household smokes, keep your child away from secondhand exposure by having a designated smoking area outside and away from the house and play areas.

If you continue to smoke while breastfeeding, the nicotine stays in your system for about 95 minutes. While little if any nicotine will pass into your breast milk, nicotine has been shown to severely limit ejection and letdown which can lead to early weaning. Nictone also lowers prolactin levels which can lead to decreased supply.

8. Tattoos

Many women wonder if it is safe to get a tattoo when they’re still nursing a child. Tattoo ink is placed into the skin with a needle. As long as you know that your tattoo artist is reputable, the parlor is sanitary, and all needles are sterile, there is little risk to you or your baby.

La Leche League states that the molecules in tattoo ink are too large to pass into breast milk. This means the only possible risk may be infection of the tattooed skin--so be sure to closely follow all of the aftercare instructions closely.

9. Over-the-Counter Acne Medication

Hormonal fluctuations and interrupted sleep patterns are your skin’s worst nightmare. Many nursing moms find the pregnancy pimples they had hoped would disappear after giving birth have stuck around.

While one common OTC acne treatment, benzoyl peroxide is deemed as safe for nursing moms, check with your doctor before using face washes or toners with salicylic acid in them. Salicylic acid is not recommended for use in children under two years of age, and the amount of salicylic acid that is absorbed in breast milk is unknown.

10. Hair Dye

Are you one of the many women who stopped coloring their hair while they were expecting? It’s common practice these days to avoid dyes while pregnant. The good news is that La Leche League states that as long as your scalp is healthy and intact, you’re fine to get your roots touched up or change color at whim.

While some of the dye's chemicals may be absorbed into your skin, it isn’t enough to hurt your nursing baby.