The PIH medical abbreviation usually means pregnancy-induced hypertension, high blood pressure that first appears during pregnancy, in prenatal and labor notes. In dermatology the same letters mean post-inflammatory hyperpigmentation, the darker patches left on skin after acne, eczema or an injury heals.
A third, more technical use appears in endocrinology, where PIH means prolactin-inhibiting hormone, another name for dopamine acting on the pituitary gland. The setting tells you which one fits. This page explains each meaning, why the pregnancy term has largely been replaced by newer names, and how PIH shows up in real records.
At a glance
Stands for
Pregnancy-induced hypertension (obstetrics)Other meanings
Post-inflammatory hyperpigmentation (skin); prolactin-inhibiting hormoneNewer pregnancy terms
Gestational hypertension, preeclampsiaSpecialty
Obstetrics, dermatology, endocrinologyWhere you see it
Prenatal records, skin clinic notes, older chartsDo not confuse with
Chronic HTN that began before pregnancy
PIH medical abbreviation pregnancy meaning
Pregnancy-induced hypertension describes blood pressure that rises for the first time after about 20 weeks of pregnancy. A common threshold is a reading of 140/90 or higher on two occasions several hours apart. PIH was used for years as an umbrella term, but most obstetric teams now name the specific condition instead.
| Current term | What it means |
|---|---|
| Gestational hypertension | New high blood pressure after 20 weeks without signs of organ strain |
| Preeclampsia | New high blood pressure plus protein in the urine or signs affecting organs such as the liver, kidneys, brain or blood |
| Chronic hypertension | High blood pressure present before pregnancy or before 20 weeks |
Because preeclampsia can become serious, the more exact labels help the whole team plan monitoring.
How pregnancy blood pressure is watched
Prenatal visits record blood pressure, weight, urine protein and symptoms at each check. If blood pressure rises, notes may add lab tests such as a CBC, liver enzymes and kidney function, and growth scans to check on the baby, since high pressure can affect the placenta and slow growth, written IUGR. Fetal monitoring tests, such as a nonstress test, may also appear.
Warning symptoms that prenatal teams commonly teach include a severe headache, vision changes, pain under the right ribs and sudden swelling of the face or hands. Plans for timing of delivery depend on the specific diagnosis and how far along the pregnancy is.
PIH in dermatology: dark marks after inflammation
In skin notes, PIH means post-inflammatory hyperpigmentation. When the skin is inflamed by acne, eczema, a burn, a bug bite or even a cosmetic procedure, pigment cells can make extra melanin. After the inflammation settles, a flat brown, tan or gray patch is left behind. It is more common and often longer lasting in people with darker skin tones.
It is different from a scar because the skin surface is usually smooth. Many patches fade over months, and dermatology notes may describe sun protection, treating the original skin condition and topical medicines such as hydroquinone, azelaic acid or retinoids.
Sample lines with PIH
Prenatal note: "G1P0 at 34 wks, PIH, BP 148/96 and 144/94 four hours apart. Urine protein neg, labs WNL, no HA or visual changes. Plan: twice weekly BP checks and NST." G1P0 means first pregnancy, WNL means within normal limits, HA means headache, and NST means nonstress test.
Dermatology note: "Acne with PIH on bilateral cheeks. Start topical retinoid, daily broad-spectrum sunscreen." Here PIH is the dark marks left after pimples healed, not anything about blood pressure.
The hormone meaning, briefly
Physiology textbooks and endocrine notes sometimes call dopamine prolactin-inhibiting hormone, or PIH, because the hypothalamus releases it to keep the pituitary from making too much prolactin. Prolactin is the hormone that supports milk production. Students meet this use in anatomy and physiology courses, but it is rare in patient charts.
If a note mentions the pituitary, prolactin levels or hormone pathways, this is the reading to consider.
Sorting out PIH in a record
- Weeks of pregnancy, blood pressure readings or urine protein point to the obstetric meaning.
- Words about acne, rash, melasma or skin tone point to the dermatology meaning.
- Mentions of the pituitary or prolactin point to the hormone meaning.
Pregnancy, skin and other diagnosis shorthand appears in the diagnosis abbreviation library, and the plain term for raised blood pressure is covered on the high blood pressure page.
This material explains the abbreviation in general terms. Your obstetric provider or dermatologist can tell you which reading fits your chart and what follows from it.
Frequently asked questions
What does PIH mean in pregnancy?
PIH means pregnancy-induced hypertension, blood pressure that first rises after about 20 weeks of pregnancy. Today most teams use more specific terms such as gestational hypertension or preeclampsia.
What does PIH mean in dermatology?
In skin care PIH means post-inflammatory hyperpigmentation. It is the darker patch left on the skin after inflammation such as acne or eczema heals.
Is PIH the same as preeclampsia?
Not exactly. PIH was an older umbrella term that included gestational hypertension and preeclampsia. Preeclampsia specifically involves high blood pressure plus protein in the urine or signs of organ strain.
Does PIH go away after delivery?
Pregnancy-related high blood pressure usually improves in the days to weeks after birth, but it can persist or even appear after delivery. Follow-up blood pressure checks are commonly arranged.
Will post-inflammatory hyperpigmentation fade?
Many dark marks fade slowly over months, especially when the skin condition that caused them is controlled and the skin is protected from sun. Deeper pigment can take longer.