PI-WIKI-PHYSL-25 · Applied Physiology · reviewed 2026-10-31
Applied Physiology, Pregnancy Physiology and Body Art
Critical numbers
Relaxin peak (highest migration risk)Around weeks 12-14 (late first trimester)
Blood volume increase~40-50% by the early third trimester; cardiac output +30-50%
Navel eversion onsetSecond half of pregnancy; often fully everted in the third trimester
Nipple and areolaAreola darkens and enlarges through pregnancy
Postpartum collagen recovery6-12 months (studio practice)
Lidocaine and the placentaCrosses the placenta
Lidocaine FDA pregnancy categoryOld Category B: no risk in animal studies, human data limited (categories retired 2015)
Caesarean section rate (global)~21% of births worldwide (2010-2018)
Safe window for new piercings postpartum6 months minimum (studio practice); longer while breastfeeding
Retainer switch deadlineWeek 12, before relaxin peaks and abdominal expansion accelerates
Navel tissue bridge removal threshold<2 mm (studio practice)
Immune changesFrom the first trimester; modulation, not simple suppression
Do not
- Waiting until the navel is visibly everted to switch to a retainer
- Using metal barbells throughout pregnancy because "the piercing has been there…
- Getting a new tattoo or piercing "early in pregnancy before I am showing"
- Using alcohol or hydrogen peroxide to clean piercings during pregnancy
- Assuming a navel piercing will return to normal after delivery
- Re-piercing through a pregnancy-stretched site too early
Applicable standards
- Professional Bodies — Studio practice
- Anaesthetic Regulation — FDA: lidocaine was in the old Pregnancy Category B (no fetal risk shown in…
- Facility Policy — Pre-operative jewellery removal