Maternity and Pregnancy Notes2

Labor and Parturition

• Labor is also known as parturition.

• Postpartum refers to the time frame after delivery, derived from "partum," which is related to parturition.

• Oxytocin drives delivery through a positive feedback loop.

  • Oxytocin is released from a gland.

  • It acts on the myometrium (middle muscle layer of the uterine wall).

  • It increases the severity and frequency of contractions.

True Labor Contractions vs. Braxton Hicks Contractions

• True labor contractions:

  • Increase in pain and frequency.

  • Felt throughout the entire abdominal pelvic cavity due to the contraction of the entire uterus.

• Braxton Hicks contractions (false labor contractions):

  • Do not increase in pain or frequency.

  • They feel like period cramps but are not as painful.

  • Felt in localized spots.

Factors Triggering Contractions

• Estrogen and progesterone ratio:

  • Estrogen facilitates uterine contractions.

  • Progesterone inhibits uterine contractions; high levels during pregnancy prevent contractions until the baby is ready.

• Estrogen dominance in non-pregnant females with severe dysmenorrhea:

  • Causes painful uterine muscle contractions even without pregnancy.

  • Supplementing with progesterone can help mitigate dysmenorrhea.

Phases of Labor

1. Dilation Phase

• Cervix dilates to 10 centimeters.

  • 10 \text{ cm is the target for full dilation regardless of baby or mom's size}

• Effacement occurs: the cervix thins and flattens out.

• Amniotic sac breaking (water breaking):

  • Not the most common first sign of labor (contractions are more common).

  • Indicates delivery is imminent due to loss of cushioning for the baby.

  • Without the amniotic sac, the baby is up against blood vessels and the placenta, which prompts the baby to want to exit.

2. Expulsion Phase

• Active labor begins when the cervix is dilated to at least 7 centimeters.

  • Things tend to speed up

• Uterine contractions increase in intensity and frequency.

• Crowning: The baby's head starts to appear outside the female's external genitalia.

• Episiotomy: May be performed if the baby's head is too large, to prevent tearing of perineal tissue.

  • Causes some bleeding, which is sutured by the OB after delivery.

• Ideal scenario: baby's head down, umbilical cord not in the way.

• Sequence: baby exits, then umbilical cord, then placenta.

Postpartum Hemorrhage

• One of the most common complications in the first 48 hours after delivery.

• Actively screened for by checking the mother frequently (e.g., every hour).

Placenta Expulsion

• The placenta must be expelled after the baby is born.

• Ideally, it follows the baby smoothly.

• If there is retained tissue, it must be manually removed.

Inducing Labor

• OB may release fluid and administer Pitocin (synthetic oxytocin) to trigger the positive feedback loop and induce contractions.

High-Risk Pregnancies

• C-sections are often preferred for more control over parameters.

• Vaginal delivery is possible but requires close monitoring with factors such as medical history considered.

Multiples

• Higher likelihood of bed rest due to pressure and movement limitations.

Prenatal Screening

• Ultrasonography

• CVS (Chorionic Villus Sampling):

  • Sample of the interlining of the uterus to look for cells from the baby.

  • Optimal timing: weeks 10-12 of pregnancy.

• Amniocentesis:

  • Sample of amniotic fluid.

  • Cells from the baby are analyzed.

  • Optimal timing: around week 15 of pregnancy.

• Maternal Blood Testing (NIPT):

  • Optimal timing: week 10 of pregnancy; earlier tests are invalid.

Common Symptoms During Pregnancy

• First Trimester:

  • Nausea, morning sickness, vomiting.

  • Vitamin B6 can help with morning sickness.

• Third Trimester:

  • Constipation due to the enlarged uterus pushing on the intestines.

  • Frequent visits to the bathroom.

Hormone Levels During Pregnancy

• hCG (Human Chorionic Gonadotropin):

  • In early pregnancy, hCG trend should be upward due to cell division.

  • Plateaus later in pregnancy.

  • Maintains corpus luteum, preventing it from becoming the corpus albicans.

  • Keeps endometrium thick and active to prevent shedding.

  • Vaginal bleeding can be a sign of impending miscarriage.

• Estrogen and Progesterone:

  • Placenta produces high amounts in the second half of pregnancy.

Importance of Progesterone and hCG

• Progesterone maintains the viability of pregnancy, especially in the first trimester (produced by the corpus luteum).

• hCG indicates viability, confirming conception, implantation, and proper development.

Additional points about hCG

• Prevents menstruation and loss of the uterine lining during pregnancy.

• Context is crucial; in healthy, non-pregnant females, hCG is absent.

• Presence may indicate certain cancers due to rapid cell division.

Recommendations During Pregnancy

• Exercise (e.g., walking) is recommended to trigger natural cortisol release from adrenal glands.

Human Chorionic Somatomammotropin (hCS)

• Communicates between the uterus and mammary glands to prepare for breast milk production.

• Comes from the placenta, travels to mammary glands.

Lactation

• Positive feedback system driven by hormones:

  • Prolactin stimulates breast milk production.

  • Oxytocin stimulates the release of breast milk.

• Lactation is highly hormonal, influenced by:

  • Progesterone which stops prolactin secretion until the baby is born.

  • Estrogen and progesterone which together are responsible for helping with the growth of the mammary glands.

Mammary Glands

• Modified sweat glands.

• Enlarge during pregnancy due to mammary gland growth and increased adipose tissue.

• After breastfeeding, mammary glands shrink, but fatty tissue may remain.

Pumping Before Birth

• Some pump colostrum before birth to induce labor provide initial nutrition to new born.

• There are no long-term complications if done correctly.

PCOS (Polycystic Ovarian Syndrome)

• Leading cause of infertility in the U.S.

• Hormone dysregulation makes it challenging to get pregnant.

• The number one thing is PCOS has a diagnostic criteria.

• Not all individuals females need an ultrasound to have a diagnosis of PCOS.

  • There are a lot of patients that are misdiagnosed because of this.

• Elevated androgens (high testosterone counts, high DHEA counts).

  • Causes hirsutism (hair growth in male-typical patterns in females).

• High testosterone disrupts estrogen-progesterone balance, leading to irregular or inconsistent cycles.

Preeclampsia

• Typically presents late in the second trimester or early in the third trimester.

• Symptoms: high blood pressure, protein in the urine, swelling.

• Treatment: induction of labor to resolve preeclampsia by delivering the baby.