Introduction to Pregnancy and Fetal Development

Flashcards covering maternal-fetal health concepts including trimesters, developmental periods, maternal physiological changes, and signs of pregnancy.

Implantation bleeding

Light bleeding that may occur about $10$ days after conception when the embryo implants in the side of the uterus, sometimes mistaken for a regular menstrual cycle.

Embryonic period

A critical developmental stage spanning from week $3$ to week $8$ ($15$ to $56$ days) where major structures like the brain, spinal column, ears, and eyes begin to form.

Teratogens

Factors in the environment that can cause birth defects, including alcohol, drugs, hormones, cigarettes, German measles, lead, mercury, and radiation.

Fetal period

The developmental timeframe from week $9$ until birth.

First trimester

Pregnancy duration from conception until the completion of the $13\text{th}$ week.

Second trimester

Pregnancy duration from the start of the $14\text{th}$ week to the completion of the $27\text{th}$ week.

Third trimester

Pregnancy duration from the end of the $28\text{th}$ week until birth.

Gestational age notation

A method of tracking pregnancy where the big number represents weeks and the second number represents days out of $7$ (e.g., $28\text{ }0/7$).

Quickening

The maternal perception of fetal movement, typically first felt between $16$ and $20$ weeks.

Surfactant

A substance produced in the lungs starting around $20$ weeks that holds alveoli open to allow for breathing after birth.

Fundus

The upper part of the uterus, which is the ideal site for placental implantation to ensure adequate nourishment and oxygen for the baby.

Placenta

A thick disc-shaped organ that provides oxygen and nutrition to the fetus while removing waste products.

Amnion

The inner fetal membrane that surrounds the baby inside the uterus.

Chorion

The outer membrane of the fetal sac.

Umbilical cord vessels

A structure consisting of two arteries and one vein ($2$ eyes and $1$ mouth) used for circulation between the placenta and the fetus.

Wharton's jelly

A slimy, jelly-like substance found inside the umbilical cord.

Dominant gene

An abnormal gene from one parent that can cause disease even if the matching gene from the other parent is normal.

Recessive inheritance

A condition requiring both genes in a pair to be defective for the disease to manifest; otherwise, the individual is a carrier.

Folic acid recommendation

The recommended intake of $400\text{ }\nu g$ (micrograms) daily for women of childbearing age, which increases to $600\text{ }\nu g$ once pregnant.

Oligohydramnios

A decreased amount of amniotic fluid that can lead to clubfoot and impaired fetal lung development.

Gravida

The total number of times a woman has been pregnant, regardless of the outcome.

Viability

The stage of pregnancy where a fetus has reached at least $20$ weeks gestation or a weight of at least $500\text{ }g$.

Preterm birth

A delivery that occurs before the completion of the $37\text{th}$ week (specifically up to $37\text{ }6/7$ weeks).

Term birth

A delivery occurring between the $38\text{th}$ to the $42\text{nd}$ week.

Post term birth

A delivery that occurs beyond the $42\text{nd}$ week of pregnancy.

Braxton Hicks

Irregular uterine contractions that do not cause labor but serve as 'practice' for the uterus.

Chadwick's sign

A bluish-purple discoloration of the cervix and vagina, one of the earliest detectable signs of pregnancy.

Hegar's sign

The softening of the lower uterine segment in preparation for pregnancy.

Goodell's sign

The softening of the cervix.

Mucus plug

A cervical seal that protects the baby from external environmental harms; its loss can indicate the onset of active labor.

Supine hypotension

A drop in blood pressure caused by the heavy uterus resting on the vena cava when the mother lies flat on her back.

Physiologic anemia of pregnancy

A condition caused by the dilution of red blood cells as plasma volume increases by up to 50\text{ }\text{%} to support the pregnancy.

Chloasma

Also known as the 'mask of pregnancy,' these are brownish patches on the face that typically disappear after birth.

Linea nigra

A dark line of pigmentation extending down the middle of the abdomen to the pubic area.

Striae gravidarum

Stretch marks found on the skin of the abdomen, thighs, or breasts that do not disappear after birth.

Progesterone

The most important hormone for maintaining pregnancy; its absence makes maintenance of pregnancy impossible.

Prolactin

The hormone responsible for preparing the breasts for lactation and breastfeeding.

Oxytocin

A hormone that stimulates uterine contractions for birth and triggers the milk ejection reflex after birth.

Presumptive signs

Subjective signs of pregnancy reported by the mother, such as nausea or fatigue, which are not reliable identifiers.

Probable signs

Objective data assessed by an examiner, such as Hegar's sign or Goodell's sign, that indicate a high likelihood of pregnancy but are not 100\text{ }\text{%} certain.

Positive signs

Definitive evidence of pregnancy including fetal heart sounds via doppler, visualization via ultrasound, or fetal movement felt by a healthcare provider.