Understanding Pregnancy Loss in the Context of Abortion Restrictions and Fetal Harm Laws

Complete abortion A sub-category of miscarriage (spontaneous abortion) in which the non-viable pregnancy tissue has completely passed from the uterus, typically without medications or surgical intervention (AAFP).
D&E Dilation and evacuation, a method used for abortions and pregnancy loss, typically from 14-28 weeks gestational age. The cervix is dilated, and the pregnancy tissue is evacuated using forceps +/- suction (ACOG).
D&X Dilation and extraction, also known as an intact D&E. A rarely used procedure whereby an abortion is completed by dilating the cervix and extracting the intact fetus from the uterus. Can also be used in stillbirth management, although its use is rare (ACOG).
Early pregnancy loss A miscarriage occurring at <13 weeks gestational age (ACOG).
Early second trimester pregnancy loss A miscarriage occurring between 13-20 weeks gestational age (ACOG).
Ectopic pregnancy A pregnancy in which the fertilized egg abnormally implants outside the uterus (not compatible with life for a developing pregnancy) (MedicineNet).
Embryo Refers to the developing pregnancy from 5 weeks gestational age through the 10th week of gestation (NIH).
Fertilization The event in which the maternal egg and the paternal sperm fuse, typically ~2 weeks gestational age (Mayo Clinic). This is sometimes referred to as conception, by the lay public. This occurs in the fallopian tube. Next, the fertilized egg will need to travel to the uterus for implantation.
Fertilization age Also called the embryonic age. Describes the time (typically in days) since fertilization of the egg. Used in scientific research to describe the early development of the pregnancy, but not used for pregnancy dating (Perinatology). Gestational age and fertilization age differ by ~2 weeks.
Fetal death/demise Synonymous with stillbirth per ACOG.
Fetus Refers to the developing pregnancy from the start of the 11th week gestation through delivery (NIH).
Gestational age Used to measure how far along a pregnancy is (pregnancy dating). Calculated by measuring in days and weeks from the pregnant individual’s first day of their last menstrual period. Menses is typically two weeks before the actual time of fertilization (sometimes referred to as conception), so pregnancy dating by gestational age actually pre-dates the pregnancy by ~2 weeks (NIH).
Heartbeat bans Refers to proposed bans on abortions past the time the first cardiac activity can be detected (usually around 6 weeks). This is often referred to in the law as the “fetal heartbeat” however it more accurately refers to the primitive cardiac activity of an embryo (the developing pregnancy is not considered a fetus until 11 weeks gestation). At the time of first cardiac activity, the heart is tubular in shape, called a primitive heart tube. See Appendix A for brief outline of cardiac development.
Implantation Describes when the fertilized egg implants into the uterine lining, at ~4 weeks gestational age (NIH).
Incomplete abortion A sub-category of miscarriage in which some of the pregnancy tissue has passed from the uterus but some is still retained in the uterus. May require treatment to completely empty the uterus and complete miscarriage in a timely and safe manner, especially if the patient is bleeding excessively (AAFP).
Induced abortion The elective termination of a pregnancy, either by medical or surgical means. Also referred to as an elective abortion, therapeutic abortion or simply an abortion. These terms are to be distinguished with spontaneous abortion, meaning a miscarriage (ACOG).
Induced miscarriage Non-medical term to describe the intentional termination pregnancy (an induced abortion), used in policy and law.
Inevitable abortion A sub-category of miscarriage in which the patient’s cervix is open, but the pregnancy tissue has not yet passed from the uterus. When the cervix is open (dilated), this is incompatible with continuing the pregnancy. The embryo or fetus may still have a heartbeat but inevitably, the pregnancy tissue will pass through the open cervix. May require treatment to complete the miscarriage (AAFP) in a timley and safe manner.
Infant death Death of a newborn child after delivery but before 1 year old (CDC).
Intrauterine fetal death/demise (IUFD) Synonymous with fetal death.
Intrauterine pregnancy A pregnancy in which the fertilized egg has implanted inside the uterus (normal location for pregnancy to develop).
Miscarriage The spontaneous loss of a nonviable, intrauterine pregnancy, before 20 weeks gestational age. Cutoff point between miscarriage and stillbirth may vary, especially in other countries (ACOG).
Missed abortion A sub-category of miscarriage in which the embryo or fetus lacks a heartbeat, but the pregnancy tissue still remains in the uterus (cervix is typically closed). Eventually, the pregnancy tissue will pass from the uterus, but may require treatment to complete the miscarriage (AAFP).
Neonatal death Death of a newborn child after delivery but before 28 days old (WHO).
Nonviable pregnancy Typically refers to when an early pregnancy lacks a gestational sac or cardiac activity (ACOG). Also more broadly refers to an embryo or fetus that is incapable of growing or developing, or incapable of sustaining life once born even with medical interventions (US Legal).
Partial birth abortion: A non-medical term used by politicians to refer to D&X procedures, and sometimes more broadly D&E procedures.
Periviable birth Delivery occurring near the limit of viability, typically from 20 weeks up to 26 weeks gestation (ACOG).
Personhood laws: Laws which seek to grant full personhood, and thus full protection under the law, to the earliest stages of human development, typically including fertilized eggs, embryos and fetuses.
Pregnancy loss Umbrella term to describe the spontaneous loss of a nonviable, intrauterine pregnancy at any gestational age.
REMS: Refers to “Risk Evaluation and Mitigation Strategies” required of certain drugs to ensure their benefits outweigh the risks. REMS vary based on the particular drug, and typically require certain information be communicated to the patient and certain prescribing protocols (FDA). Mifepristone currently requires a REMS which allows only certified providers and certain healthcare settings to administer the medication, despite its low risk of adverse events.
Septic abortion Refers to a miscarriage or an induced abortion which is complicated by an intrauterine infection.  Can be life-threatening and requires prompt treatment (AAFP).
Spontaneous abortion A medical term for miscarriage (pregnancy loss <20 weeks) (ACOG).
Stillbirth The spontaneous loss of a nonviable, intrauterine pregnancy, typically after 20 weeks gestational age per ACOG and the CDC. In clinical practice, may refer to pregnancy loss after 28 weeks, synonomous with a late intrauterine demise. Cutoff point for gestational age to distinguish miscarriage and stillbirth may vary, especially in other countries. Upon delivery of the fetus, no signs of life are present (no breathing, heartbeat, voluntary movements).
Threatened abortion Refers to when a patient experiences vaginal bleeding in early pregnancy, but the cervix is closed and the heartbeat can still be found. This scenario may progress to a miscarriage, or symptoms may resolve and the pregnancy continues (AAFP).
Trimester Pregnancy has traditionally been divided into 3 trimesters; ≤ 13 weeks GA is considered 1st trimester, from 14-27 weeks GA is considered 2nd trimester and ≥28 weeks GA until delivery is considered 3rd trimester. Some medical organizations are moving away from use of trimesters as referring to the exact gestational age is more specific (ACOG).
Unborn child A non-medical term used by politicians to refer to a developing pregnancy. Does not consistently refer to a specific stage in human development.
Viability The ability for a fetus to survive outside the uterus for a sustained amount of time, with or without medical interventions (AOCG). Viability depends on many factors, including gestational age, fetal weight and sex, and medical interventions available. Viability does not refer to a specific gestational age; it is generally considered to be around 24 weeks gestation but can be later or earlier depending on the pregnancy (Ibis Reproductive Health).
Zygote A fertilized egg, containing both maternal and paternal DNA (NIH).
Appendices