Pregnancy is over, and your baby is finally here! And with that comes the much-awaited return to some of your favorites, like a hot yoga class and the occasional double-shot latte.

But before you resume your pre-pregnancy life, there are still a few don’ts — like smoking weed or pot (aka cannabis) — that should remain on the naughty list.

Here are the facts you should know about smoking weed while breastfeeding.

If you used cannabis before pregnancy, you might wonder whether it’s something you can safely resume now that your little one is here. The short answer is “no” — and here’s why.

According to the American Academy of Pediatrics (AAP), data on the effects of exposing infants to weed via breast milk is lacking. As such, the AAP discourages maternal cannabis use while breastfeeding.

The AAP’s official statement on the use of weed by breastfeeding mothers states that the risks are unknown. For this reason, you need to know the potential risk — and avoid cannabis products while breastfeeding.

And that’s exactly what Gina Posner, MD, a pediatrician at MemorialCare Orange Coast Medical Center, tells her families. “There has not been enough research conducted to know if marijuana is harmful or not to a baby. While we do know that it is passed through the breast milk, it’s likely that there are some effects to the baby,” says Posner.

Tetrahydrocannabinol (THC), the main ingredient in weed, is fat soluble and accumulates in breast milk. The Food and Drug Administration (FDA) reports that THC can remain in breast milk for up to 6 days.

But it’s not just THC that breastfeeding parents need to be concerned about, according to Tamika Cross, MD, FACOG, and board-certified OB-GYN. “Often, there are other contaminants such as heavy metals, bacteria, and pesticides in marijuana that are harmful to mom and baby,” she says.

In addition to the risk of passing THC or contaminants to your baby via breast milk, experts believe that smoking pot could impair a parent’s ability to care for their infant.

According to the FDA, using cannabis while breastfeeding can harm your baby. More specifically, it says THC may affect a newborn’s brain. Although more research is needed, it points to hyperactivity and poor cognitive function, among other long-term consequences.

Additionally, researchers say it’s reasonable to speculate that THC or cannabidiol (CBD) exposure during breastfeeding could alter brain development in infants. This is based on previous studies that have suggested that prenatal exposure to cannabis may lead to deficits in cognitive and behavioral function.

A small study published in the journal Obstetrics and Gynecology analyzed breast milk samples from mothers who regularly consumed cannabis.

Researchers found that an exclusively breastfeeding infant ingests an estimated 2.5 percent of the maternal dose (a range of 0.4 to 8.7 percent). This equates to about 8 micrograms of THC per kilogram of body weight over the course of a day.

Although that may not sound like a lot, experts are still very concerned about the potential effect of cannabis on a developing infant, and more specifically, on their brain. It’s important to note that the researchers measured the THC in breast milk, not in the infant’s blood.

The pump and dump method may work after a glass of wine, but it’s not going to help if you’ve been smoking weed.

You shouldn’t use the pump and dump method, says Cross, because cannabis is still in breast milk for several days after use. “There’s no way to know how long the marijuana will remain in your system, as it varies person to person,” she explains.

A study published in the journal Pediatrics found that THC was detectable in 34 of the 54 samples of breast milk up to 6 days after the last reported use.

Although the estimated daily dose of THC ingested by the infant was lower than an adult dose, researchers pointed out that there was a high variability in breast milk concentrations. This means some infants may be exposed to amounts closer to an adult’s daily dose.

Major organizations like the Centers for Disease Control and Prevention, American Academy of Pediatrics, and American College of Obstetricians and Gynecologists all agree that no amount of cannabis has been proven safe to use while breastfeeding.

In other words, they recommend avoiding pot for the duration of breastfeeding. Additionally, the CDC states that mothers should be advised not to use products containing CBD in any form while breastfeeding.

CBD oil is a popular product for a wide range of health conditions, including anxiety, pain, insomnia, and stress. Unfortunately, there’s little to no research on the safety of using CBD oil while breastfeeding.

This leaves many breastfeeding mamas to decide whether the pros outweigh the potential cons with their healthcare provider. That said, most experts recommend against its use while breastfeeding, citing a lack of evidence supporting its safety.

According to the FDA, one concern, in particular, is the potential for CBD products to be contaminated with substances like THC, which may pose a risk to a breastfed baby. This is especially concerning, as CBD is largely unregulated by the FDA. In other words, CBD products don’t need approval from the FDA before landing on store shelves or online.

Is CBD legal? The 2018 Farm Bill removed hemp from the legal definition of marijuana in the Controlled Substances Act. This made some hemp-derived CBD products with less than 0.3% THC legal at the federal level. However, CBD products containing more than 0.3% THC still fall under the legal definition of marijuana, making them illegal at the federal level. Some states have legalized CBD, so be sure to check state laws, especially when traveling. Also, keep in mind that the FDA has not approved nonprescription CBD products, and some products may be inaccurately labeled.

Even if you’re not breastfeeding, experts recommend staying away from cannabis. Infants and other children in a household can be exposed to pot if adults in the home are smoking.

Data on the effects of passive (second-hand) cannabis smoke is still emerging, but experts say it’s not safe. In fact, the FDA states that cannabis and tobacco smoke contain many of the same harmful components, making them both unsafe around infants and children.

Medicinal use of cannabis is on the rise, as many in the health and wellness industry recommend it as a treatment for various conditions, including anxiety, chronic pain, and insomnia.

But while this method of managing symptoms is showing signs of success, using cannabis for medicinal purposes isn’t recommended if you’re breastfeeding.

Cross says it’s important to understand the potential risks of exposing your infant to cannabis, as well as the benefits of breastfeeding, and make the best decision for you and your little one with the help of a licensed medical provider.

If you use cannabis medicinally, Posner says to try to find an alternative treatment plan with your doctor or psychiatrist. “There are medicines that are safe during breastfeeding that can help with anxiety and other problems that THC is usually used for,” she adds.

Major health and medical organizations like the AAP, CDC, and ACOG all agree that breastfeeding moms should be counseled on the dangers of using cannabis products while breastfeeding.

Along with the FDA, these groups advise against the use of cannabidiol, tetrahydrocannabinol, and cannabis in any form, especially since studies show that breast milk can contain THC for up to 6 days after use.

It’s always best to talk to your doctor or your child’s pediatrician if you have questions about using any drug or other substance while breastfeeding.