A medical point of view
A question that is frequently asked amongst divers and during medical examinations is: Can I dive during pregnancy?
The answer is a clear “No”.
As soon as divers find out that they are pregnant, they should stop diving immediately. This restriction is lifted after the baby is born. Although this answer sounds rather absolute and drastic, this nine-month “break” from diving is certainly not as serious as a birth defect in the baby or even miscarriage.
The reason for this firm “No” is because it cannot be safely determined that diving during one’s pregnancy will not damage the foetus. In fact, it may cause the mother to suffer a miscarriage. However, medical studies involving pregnant divers have not been done to verify this - due to ethical grounds.
Nevertheless, there are indeed reports about divers who had dove during their pregnancy and still gave birth to healthy babies. However, this can hardly serve as a research model
The foetus receives its oxygen and nutrients via the umbilical cord. In the early stages of pregnancy. The foetal lungs have not fully developed, so the blood almost completely bypasses the lungs. The exchange of substances (nutrients and oxygen) takes place between the open foramen ovale (between the right and left atrium) and the ductus arteriosus (a blood vessel between two large out-going and incoming blood vessels). Through these two vessels, gas bubbles may freely travel from the venous to the arterial side.
The consequence of decompression arises in the maternal blood and may be transported to the foetus via the umbilical cord. Although the placenta is a natural filter, it may fail to do its job in the presence of supercritical saturation. Hence, nitrogen saturation or narcosis of the placenta or foetus is a possibility. Such cases may lead to bubbles forming in the foetus’ blood, a condition that may be fatal.
A safe depth for pregnant women simply does not exist. Although the development of gas bubbles at shallow depths is unlikely, In addition, if an expectant mother were to require any decompression therapy following a diving accident, it is unclear how this would affect the unborn child.
Couples who want to have children should consider the timing of the pregnancy, when planning a dive holiday. In this way, there would be no reason to terminate a pregnancy in case the dates for the holiday and time of pregnancy happen to clash.
After childbirth and lactation
After giving birth, when the body (or wound, in the case of Cesarean section) has healed, the mother should start to regain her fitness when she feels comfortable and relaxed, if she wants to start to dive again.
After pregnancy and childbirth, the pelvic ring, pubic symphysis, pelvic floor and tapes are still loose after stretching. Any heavy lifting may lead to a bladder accident. Hence, if the mother goes back to diving, she can ask the proud father to help with the carrying of heavy cylinders and weight belts, and tightening of the BCD.
At the lactation stage, caution is still advised. Nitrogen bubbles are easily soluble in fat and dissolve nicely in breast milk. However, they become largely diluted during suction, and also inside the baby’s stomach.
Damage caused by nitrogen bubbles are not a concern. Instead, it is the wide-open milk ducts that poses a problem, as they represent an entry point into the baby’s body. If the mother suffers from mastitis (breast infection), a total dive ban is a must.
In general, it is extremely important for mothers to pay attention to proper hydration. This is because she may need to drink much more water than usual after she starts to breastfeed. If she experiences a decline in milk production, it is usually due to a decrease on water intake.