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The folds of skin at the opening of the vagina consisting of large outer folds called the labia majora and inner folds called the labia minora.


Laceration ( Tear )

A cut or tear in tissues. Spontaneous lacerations of the perineum (the area between the vagina and anus) may occur as a result of childbirth. Perineal lacerations are classified by degree.

  • First-degree: The laceration  is limited to  the perineal skin and/or vaginal mucosa.
  • Second degree: The laceration involves the perineal skin and/or vaginal mucosa, and extends through the underlying fascia and muscles. It does not involve the rectal sphincter.
  • Third degree: The laceration involves the perineal skin and/or vaginal mucosa, and extends through the underlying fascia and muscles.The laceration involves the anal sphincter.
  • Fourth degree: The laceration involves the perineal skin and/or vaginal mucosa, and extends through the underlying fascia , muscles, and anal sphincter . The laceration extends through the rectal mucosa. 


The production and excretion of milk by the breast.

Lamaze (Lamaze method)

 A method of childbirth preparation using behavioral techniques to reduce pain and anxiety in labor developed by the obstetrician Ferdinand Lamaze (1891-1957).


The fine hair that covers the fetus.

Large for gestational age (LGA)

A birth weight equal to or greater than the 90th percentile for a given gestational age.

ACOG Practice Bulletin No.22: Fetal Macrosomia. American College of Obstetricians and Gynecologists, Washington DC 2000

Late deceleration

A gradual decrease in the fetal heart rate with onset of deceleration to nadir >30 seconds. The nadir of the deceleration occurs after the peak of the contraction

Late decelerations are believed to be caused by low oxygen blood levels in the fetus which causes constriction of peripheral blood  vessels in order to divert blood to vital organs. Constriction of peripheral blood  vessels leads to hypertension which stimulates a baroreceptor mediated vagal response resulting in a decreased heart rate.

Any decrease in uterine blood flow or placental dysfunction can cause late decelerations.

LDRP (labor ,delivery ,recovery, and postpartum  room)

A room designed to accommodate labor, delivery, and recovery. The rooms are not usually equipped to handle cesarean section deliveries.
Lemon Sign

Narrowing of the frontal bones of the skull giving the fetal head the shape of a lemon.  Most commonly seen with Arnold-Chiair II malformation and open spina bifida early in gestation.

The lemon sign is not specific for open spina bifida and may be seen in 1% of normal fetuses.

Leopold's maneuvers

4 specific steps in palpating the uterus through the abdomen in order to determine the lie and presentation of the fetus.


The longitudinal axis of the fetus in relation to the mother's longitudinal axis (i.e.,  longitudinal would be parallel to the mother).


An infection caused by eating food contaminated with the bacterium Listeria monocytogenes, L monocytogenes is a gram-positive, motile, rod-shaped bacterium.

About one-third of listeriosis cases happen during pregnancy. Fetal infection can occur via transplacental transmission. Infected pregnant women may experience only a mild, flu-like illness with fever or stiff neck .  Infections during pregnancy can lead to miscarriage or stillbirth, premature delivery, or infection of the newborn.

The bacterium has been found in a variety of raw foods, such as uncooked meats and vegetables, soft cheeses and and ice cream made with unpasteurized cheese, deli meats, refrigerated pts or meat spreads.


L&D (L and D)

Labor and Delivery.

Lightening (dropping, engagement)

The descent of the presenting part of the fetus into the pelvis.


Last menstrual period. Refers to date of onset of the last menstrual period.


Left occiput anterior. Describes the position of the fetal occiput as being to the left side of the maternal birth canal (position) and anterior in relation to the mother's pelvis (variety).

Low-lying placenta

The placental edge is less than 2 centimeters (cm) from the internal os but not covering the internal os.

Patients with a low lying placenta appear to have an increased risk for vasa previa.

LifeART   2006 Lippincott Williams & Wilkins. All rights reserved.

Reddy UM, etr al. Fetal imaging: Executive Summary of a joint Eunice Kennedy Shriver National institute of child health and human development, society for maternal-fetal medicine, American institute of ultrasound in medicine, American college of obstetricians and gynecologists, American college of radiology, society for pediatric radiology, and society of radiologists in ultrasound fetal imaging workshop. J Ultrasound Med. 2014 May;33(5):745-57. PMID:24764329

Dashe JS, eta al. Persistence of placenta previa according to gestational age at ultrasound detection. Obstet Gynecol. 2002;99:692-7.
PMID: 11978274


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