Few things in life are as readily stress-relieving as a soak in the tub. And for years, some expectant women have used the inherent relaxing qualities of water to make the labor and birthing process more peaceful. But is a water birth safe for both mom and baby?

Before diving into the safety of this modern birth method, it’s important to know what a water birth is. According to the American Pregnancy Association, a water birth involves a mother giving birth in a tub of, you guessed it, warm water. The APA notes that some mothers will labor in the water and get out for the delivery, while others stay in the tub for the entire birthing process. Sounds pretty relaxing right?

As water births grow in popularity, it’s important to look into the safety of this birthing method. And, as is with many pregnancy topics, the reviews are mixed. A 2014 statement from the American College of Obstetricians and Gynecologists declares that water immersion during the initial stages of labor is reportedly safe and may help decrease labor pain. ACOG also noted, however, that the safety and efficacy of immersion in water during the second stage of labor have not been established. In fact, there may not be any benefits to delivering your child in this way. (It should be noted that the American Association of Birth Centers was concerned that the ACOG and AAP opinion statement did not adequately account for water births attended by skilled midwives.)

Although more research on water births is needed for conclusive results, there have been cases of babies getting a deadly infection after water birth or nearly drowning from breathing in tub water. Underwater delivery may also cause difficulties in the baby’s regulation of body temperature, as well as an increased potential for damage to the umbilical cord.

But don’t let this doom and gloom totally dissuade you from considering a water birth if you’re interested. For instance, certified doula Christine Strainhas tells me in an interview that she had great success with water births for her clients.

“From a doula perspective, every client I have supported through water birth has loved the experience,” she says. “I think waterbirth is a great option that should be more widely available in hospitals.” She does acknowledge, however, that water births are not for everyone.

“Not every woman who desires a water birth will end up having one, so it is important to be flexible and open to the possibility that hey may not actually birth in the water.”

With all of this in mind, it is up to the mother and her medical team to decide if a water birth is the best fit. There are, however, some situations in which a water birth is a definite no-go. Here are seven cases in which a pregnant woman may be unable to give water birth.